MyEnvironment v VicForests [2013] VSCA 356

STATUTORY INTERPRETATION - Construction where competing purposes - Kelly v The Queen [2004] HCA 12; (2004) 218 CLR 216 considered - Nicholls v The Queen [2005] HCA 1; (2005) 219 CLR 196, Carr v Western Australia [2007] HCA 47; (2007) 232 CLR 138 and Construction Forestry Mining and Energy Union v Mammoet Australia Pty Ltd [2013] HCA 36; (2013) 87 ALJR 1009 applied - Victims Compensation Fund v Scott Brown & Ors [2002] NSWCA 155 (Spigelman CJ in dissent) considered.

1 I have had the considerable benefit of reading the draft judgment of Tate JA. I agree with her Honour's reasons. I also add some additional observations on the statutory construction issue, considered in Tate JA's reasons, that arises in response to the appellant's submissions that the purpose of the relevant legislation is to protect the habitat of the Leadbeater's possum, and that the Court should endeavour to construe the relevant provisions expansively with a view to furthering this legislative purpose.

2 The purposive approach to statutory interpretation, as embodied in s 35 of the Interpretation of Legislation Act 1984, provides that a construction that would promote the purpose or object underlying the Act or subordinate instrument shall be preferred to a construction that would not promote that purpose or object. Both the Leadbeater's Possum Action Statement ('LBP AS') and the Central Highlands Forest Management Plan ('the plan'),[1] being subordinate instruments, fall to be construed in accordance with this provision.

3 The trial judge referred to two authorities when setting out the applicable principles of construction:[2]

In CIC Insurance Ltd v. Bankstown Football Club Ltd,[3] Brennan CJ, Dawson J, Toohey J and Gummow J stated:

It is well settled that at common law, apart from any reliance upon s 15AB of the Acts Interpretation Act 1901 (Cth), the court may have regard to reports of law reform bodies to ascertain the mischief which a statute is intended to cure. Moreover, the modern approach to statutory interpretation (a) insists that the context be considered in the first instance, not merely at some later stage when ambiguity might be thought to arise, and (b) uses 'context' in its widest sense to include such things as the existing state of the law and the mischief which, by legitimate means such as those just mentioned, one may discern the statute was intended to remedy. Instances of general words in a statute being so constrained by their context are numerous. In particular, as McHugh JA pointed out in Isherwood v Butler Pollnow Pty Ltd, if the apparently plain words of a provision are read in the light of the mischief which the statute was designed to overcome and of the objects of the legislation, they may wear a very different appearance. Further, inconvenience or improbability of result may assist the court in preferring to the literal meaning an alternative construction which, by the steps identified above, is reasonably open and more closely conforms to the legislative intent.[4]

In Project Blue Sky Inc v Australian Broadcasting Authority,[5] McHugh, Gummow, Kirby and Hayne JJ stated:

[69] The primary object of statutory construction is to construe the relevant provision so that it is consistent with the language and purpose of all the provisions of the statute. The meaning of the provision must be determined 'by reference to the language of the instrument viewed as a whole'. In Commissioner for Railways (NSW) v Agalianos, Dixon CJ pointed out that 'the context, the general purpose and policy of a provision and its consistency and fairness are surer guides to its meaning than the logic with which it is constructed'. Thus, the process of construction must always begin by examining the context of the provision that is being construed.

[70] A legislative instrument must be construed on the prima facie basis that its provisions are intended to give effect to harmonious goals. Where conflict appears to arise from the language of particular provisions, the conflict must be alleviated, so far as possible, by adjusting the meaning of the competing provisions to achieve that result which will best give effect to the purpose and language of those provisions while maintaining the unity of all the statutory provisions. Reconciling conflicting provisions will often require the court 'to determine which is the leading provision and which the subordinate provision, and which must give way to the other'. Only by determining the hierarchy of the provisions will it be possible in many cases to give each provision the meaning which best gives effect to its purpose and language while maintaining the unity of the statutory scheme.

[71] Furthermore, a court construing a statutory provision must strive to give meaning to every word of the provision. In The Commonwealth v Baume Griffith CJ cited R v Berchet to support the proposition that it was 'a known rule in the interpretation of Statutes that such a sense is to be made upon the whole as that no clause, sentence, or word shall prove superfluous, void, or insignificant, if by any other construction they may all be made useful and pertinent'.[6]

4 Whilst there is no doubt that these authorities endorse a purposive approach

4 to statutory construction, the authorities also show that caution is required when seeking to interpret a particular provision expansively because it is perceived that the legislation as a whole pursues an underlying purpose. Several of these authorities are cited in the reasons of Tate JA[7].

5 Justice Tate refers to the observations of Gleeson CJ in Carr v Western Australia where his Honour held:

In the interpretation of a provision of an Act, a construction that would promote the purpose or object underlying the Act is to be preferred to a construction that would not promote that purpose or object. As to federal legislation, that approach is required by s 15AA of the Acts Interpretation Act 1901 (Cth) ('the Acts Interpretation Act'). It is also required by corresponding State legislation, including, so far as presently relevant, s 18 of the Interpretation Act 1984 (WA). That general rule of interpretation, however, may be of little assistance where a statutory provision strikes a balance between competing interests, and the problem of interpretation is that there is uncertainty as to how far the provision goes in seeking to achieve the underlying purpose or object of the Act. Legislation rarely pursues a single purpose at all costs. Where the problem is one of doubt about the extent to which the legislation pursues a purpose, stating the purpose is unlikely to solve the problem. For a court to construe the legislation as though it pursued the purpose to the fullest possible extent may be contrary to the manifest intention of the legislation and a purported exercise of judicial power for a legislative purpose.[8]

6 The observations of Gleeson CJ in Carr were recently cited with approval by the High Court in Construction Forestry Mining & Energy Union v Mammoet Australia Pty Ltd.[9] There, Crennan, Kiefel, Bell, Gageler and Keane JJ, observed that 'the idea contained in the last paragraph of this passage [set out above] was pithily expressed by the Supreme Court of the United States in Rodriguez v United States: "[N]o legislation pursues its purposes at all costs."'[10]

7 The passage of the Supreme Court of the United States to which the High

7 Court referred has been frequently cited in Australian authorities.[11] When set out in full, it provides:

[N]o legislation pursues its purposes at all costs. Deciding what competing values will or will not be sacrificed to the achievement of a particular objective is the very essence of legislative choice - and it frustrates rather than effectuates legislative intent simplistically to assume that whatever furthers the statute's primary objective must be the law.[12]

The decision continued, quoting previous decisions of that Court:

'Where, as here, "the language of a provision . . . is sufficiently clear in its context and not at odds with the legislative history, . . . '[there is no occasion] to examine the additional considerations of "policy" . . . that may have influenced the lawmakers in their formulation of the statute.'[13]

8 This principle is still accepted and applied by the US Courts.[14]

9 A similar observation to that made in Rodriguez v United States was made around the same time by Mahoney JA in Metal Manufacturers Pty Ltd v Lewis.[15] That case concerned the interpretation and application of s 556(2)(a) of the Companies (New South Wales) Code which provided company directors with a defence to liability for certain debts incurred by the company whilst insolvent. The section provided:

(2) In any proceedings against a person under sub-section (1) it is a defence if the defendant proves -

(a) that the debt was incurred without his express or implied authority or consent.

[T]o see the key to the meaning of a section in the policy or purpose of the legislation is, in my opinion, to take a less than sophisticated view of the art of the parliamentary draftsmen. In many cases, the interpretation of a provision is difficult, not because the policy or purpose of the legislation is not clear, but because the section is directed, not simply to effecting that policy or purpose, but to achieving a compromise between it and other considerations. In the present case, the evil and the remedy are clear. The draftsmen sought to prevent the improper incurring of debts and to do so by imposing criminal and civil liability on relevant directors. The difficulty that arises in the interpretation of [the Companies (New South Wales) Code] s 556(2) arises because, having the mischief and the remedy clear, the draftsman had to determine the 'true reason' of the remedy chosen, that is, how far he should apply it without infringing the rights of otherwise innocent directors. I do not think that policy or purpose are of assistance in determining whether a director should be responsible for all debts incurred by his managing director or only for those to which he has given a particular authority or consent.[16]

10 Victims Compensation Fund v Scott Brown & Ors[17] provides a further example. That case concerned a claim for compensation under the Victims Support and Rehabilitation Act 1996 (NSW) which turned on whether the word 'and' in cl 5(a) should be given its ordinary conjunctive meaning or should be read disjunctively. Clause 5(a) of Schedule 1 of the Act provided that:

Compensation is payable only if the symptoms and disability persist for more than 6 weeks.

11 The comments of Spigelman CJ (dissenting) are apposite:

In the present proceedings, the respondent submitted that the purpose was to compensate victims. Even if I were to accept a legislative purpose stated at that level of generality, that would not entail that any ambiguity must be construed in such a way as to maximise compensation (cf Favelle Mort Ltd v Murray 179). In any event, the very specificity of the provisions of the legislation indicate that the legislative purpose is to provide compensation in accordance with the Act and not otherwise.[18]

12 On appeal to the High Court, Heydon J (with whom McHugh ACJ, Gummow, Kirby and Hayne JJ agreed) endorsed the reasoning of Spigelman CJ. His Honour made the following observations which, in my view, apply equally in this case:

The reasoning of the majority in the Court of Appeal

The principal argument in favour of the disjunctive construction which attracted the majority of the Court of Appeal was that the legislation had remedial and beneficial objectives, one of which was, as stated in s 3(a) of the Act, 'to give effect to a statutory scheme of compensation for victims of crimes of violence'. It may be accepted at once that the legislation did have remedial and beneficial objectives. While at common law the victim of a criminal act of violence can sue the perpetrator for the tort of battery, and, depending on the circumstances, other torts, commonly the criminal will have vanished, or will lack any assets with which to satisfy a judgment.

The majority considered it to follow that the legislation should be construed by taking 'a liberal approach'. The 'injury of shock' comprised 'conditions attributed to post traumatic stress disorder, depression and similar conditions' having psychological and physical symptoms and leading to disabilities. This, it was said, supported the interdependence of the five parts of cl 5. Since it would only be a rare case in which symptoms and disabilities did not coexist, there was no reason to construe cl 5(a) as creating 'a mandatory cumulative requirement' because this would not 'promote the broad and beneficial legislative purpose'. It was also said that 'symptoms and disability' was a 'composite or portmanteau phrase in its context'.

The "remedial and beneficial objectives" argument

To begin consideration of issues of construction by positing that a 'liberal', 'broad', or 'narrow' construction will be given tends to obscure the essential question, that of determining the meaning the relevant words used require. Although the purpose of the Act is beneficial, it does not follow that recovery is contemplated for every act of violence or every consequence that could be described as an injury. The numerous injuries set out in the Table to Sched 1 (which extends over twelve pages) are identified with considerable precision. The clauses in Sched 1 which precede the Table, too, are drafted with some attempt at precision. The legislation confers benefits, and no doubt it should not be construed restrictively, but in dealing with specific limited words like those of cl 5, it is not open to apply much liberality of construction. It is difficult to state the legislative purpose except at such extreme levels of generality that it is not useful in construing particular parts of the legislative language. As Spigelman CJ said: "The issue before the Court is the determination of the circumstances in which compensation is payable." The legislation has endeavoured to define these circumstances in precise language which does not permit universal recovery; and hence "[t]he Court is not required to give the most expansive possible interpretation of such circumstances". [19]

13 As the author R S Geddes notes, after referring to the decisions in Victims Compensation Fund Corporation v Brown, '[a]lthough it is tempting to seize upon a statement of purpose in an Act and to strive for an interpretation that furthers the purpose as defined, the task of relevantly defining purpose may be more complex.'[20]

14 In my view, the authorities can be seen as supporting two related propositions. First, that it is rarely, if ever, the case that legislation pursues a single purpose to the fullest extent possible. Rather legislation is typically the result of a carefully considered attempt at balancing multiple and sometimes competing objectives. To assume that the apparently confined words of a provision must be given an expansive operation on the basis of what is perceived to be the legislation's primary purpose may frustrate rather than effectuate legislative intent.

15 In this case, as the reasons of Tate JA demonstrate,[21] the legislative scheme pursues multiple purposes. In particular, it seeks to ensure the protection of the habitat of the Leadbeater's possum whilst at the same time allowing for the continued extraction and production of timber from forests. The relevant question is where the legislature has determined that the appropriate balance should lie.

16 Secondly, even when a single, or significant legislative purpose can be clearly perceived, such a purpose may be articulated at a level of generality that makes it unhelpful when construing a particular provision which manifests a more specific legislative intent.

17 Whilst it is clear that the protection of the habitat of the Leadbeater's possum is a significant purpose of the LBP AS and the plan, the LBP AS and the plan provide that such protection is to be achieved by categorising areas of habitat into three zones, each of which provides for a different level of protection.[22] The specificity of the criteria used to determine the zone within which an area of habitat falls, and the differing restrictions on timber extraction that such a categorisation entails, support the view that the relevant legislative purpose is to provide protection in accordance with the LBP AS and the plan and not otherwise. To submit, as the appellant did, that the purpose of the relevant legislation is to protect the habitat of the Leadbeater's possum is to state a purpose at a level of generality that is of little assistance when construing the relevant provisions.

18 Whilst there is no doubt that the provisions in the LBP AS and the plan should not be construed restrictively, on the basis of these authorities, the submission that the legislative purpose of ensuring the survival of the Leadbeater's possum should be used to construe the provision in order to provide the 'fullest relief which the fair meaning of its language will allow'[23] cannot be accepted. The issue before the Court is the determination of the criteria which habitat must meet in order to fall within the definition of Zone 1A. These criteria have been considered and drafted with some attempt at precision. To approach the issue of construction by positing that an expansive construction that furthers the purpose of protecting the habitat of the Leadbeater's possum should be preferred obscures the essential question, that of determining the meaning that the relevant words used require in the context in which they occur.

Introduction .............................................................................................

Injunctions to restrain logging .............................................................

Protection of the LBP ............................................................................

The statutory context .............................................................................

(1) The CFL Act ......................................................................

(2) The Forests Act ..................................................................

(3) The SFT Act ......................................................................

(4) The FFG Act ......................................................................

The regulatory context ...........................................................................

(1) The LBP AS .......................................................................

(2) The plan .............................................................................

The reasons of the trial judge ................................................................

(1) The conclusion on the construction of the LBP AS ...........

(2) The conclusion on the inter-dependence of the LBP AS and the plan .......................................................................

(3) The conclusion on the construction of the plan .................

- disjunctive or conjunctive? ..........................................

retention harvesting proposal .............................................

The Notice of Appeal ..............................................................................

Did the trial judge err in his construction? ........................................

(1) Statutory construction in the face of competing purposes

(2) The separate category construction in the LBP AS ...........

(3) The construction of the plan - Table 3.2 ...........................

(4) Are the words 'mature' and 'senescing' vague?...............

The Notice of Contention: ....................................................................

Conclusion: .............................................................................................

19 The survival of the endangered Leadbeater's Possum is directly linked to the availability of hollow-bearing trees that can be used for nesting and shelter. The Central Highlands of Victoria contains forests of Mountain Ash, Alpine Ash and Shining Gum that serve as habitat for the Leadbeater's Possum by the presence of a combination of large living and dead hollow-bearing trees and a dense understorey of acacia trees. These forests are also suitable for timber harvesting. The Forest Management Plan for the Central Highlands seeks to ensure that the Leadbeater's Possum survives and flourishes by creating zones of Leadbeater's Possum habitat in which timber harvesting is either excluded or permitted but regulated. It uses a specific density of hollow-bearing trees as the primary criterion for the habitat that warrants the highest form of protection; that is, the zone in which timber harvesting is excluded, Zone 1A. The central dispute between the parties turns on the proper construction of Zone 1A of the relevant Forest Management Plan: is the density of hollow-bearing trees, as prescribed under the relevant Forest Management Plan, limited to 'old' hollow-bearing trees or does it extend to hollow-bearing trees regardless of age? The latter would potentially increase areas of the Central Highlands excluded from logging.

20 This appeal is brought by MyEnvironment Inc ('MyEnvironment') against orders made by Osborn JA dismissing an application to restrain the respondent, VicForests, from resuming logging in one part of the forest of the Central Highlands in Toolangi, Gippsland, known as the 'Gun Barrel' coupe.[24] His Honour also refused an application to restrain VicForests from commencing logging in two other parts of the Central Highlands forest, known as the 'South Col' and 'Freddo' coupes. All three coupes will be referred to collectively as the 'Toolangi coupes'. VicForests has undertaken not to log the Toolangi coupes pending the outcome of the appeal.[25]

21 The basis advanced by MyEnvironment for the injunctions was that the Toolangi coupes, if properly assessed and zoned under the relevant legislation and the relevant Forest Management Plan, satisfy the density requirements of hollow-bearing trees ('HBT'), with the result that they are not available for timber harvesting because they are excluded as the most highly protected habitat of the endangered Leadbeater's Possum ('LBP').[26]

22 His Honour rejected the case presented by MyEnvironment and held that the density of HBT required to attract the greatest degree of protection depended upon the HBT being old HBT and not any HBT regardless of age. This finding lies at the heart of the appeal. More specifically, he held that the HBT could be either mature or 'senesecing'. 'Senescing' conveys deterioration with age and is explained below. In addition, VicForests, by means of a Notice of Contention, claims that the HBT must exhibit both the characteristics of being mature and senescing and not simply one attribute or the other.

23 For the reasons that follow, the appeal should be dismissed. The submissions of MyEnvironment seek to construe the relevant regulatory instruments as though they had a single purpose, the conservation of the LBP, when in fact they have multiple purposes and are directed to achieving a balance between the maintenance of native fauna and the ecologically sustainable long-term timber production capacity of forests. The relevant regulatory instruments, informed by the preponderance of scientific evidence, and read as a whole, are directed at excluding from logging 'old' HBT, that is, mature or senescing living HBT. Zone 1A habitat is defined in order to protect only the preferred habitat of the LBP and not to sequester all suitable habitat.

24 The LBP is a small non-gliding arboreal marsupial, distinguished by grey fur with a black dorsal stripe. The wild populations are confined to Victoria, where it is the State's official faunal emblem. The survival of the species, which has been listed as a threatened taxon under the Flora and Fauna Guarantee Act 1988 ('the FFG Act'),[27] is dependent on conservation measures undertaken in Victoria. For much of the 20th century it was thought to have become extinct, until it was rediscovered in the wet Mountain Ash, Alpine Ash and Shining Gum forests (collectively 'montane ash forests') of the Central Highlands of Victoria in 1961.[28]

25 The LBP is a colonial species and can live in groups of two to 12 individuals, with a typical home range of 1.5 to 3 ha. It feeds on sap from acacia trees, honeydew produced by sap-sucking insects and invertebrates such as large flightless tree crickets that inhabit bark streamers on large eucalypt trees.[29] The LBP nests inside the hollows of living or dead trees. It spends about 75 per cent of its time inside these hollows, with individuals of a given colony swapping regularly between several different trees within a given area. HBT are therefore critical for the LBP's survival. In addition, the acacia understorey of montane ash forest is important for providing the sap that is a key source of food, as well as giving a dense interconnected substrate used by the LBP to move rapidly through the forest.[30]

26 The LBP is dependent upon the maintenance of its habitat in order to survive. One of two significant threats to its survival is the effect of wildfires.[31]

27 The forests of the Central Highlands have been susceptible to fires. Five major bushfires have occurred in the area in the last 100 years,[32] including the 'Black Friday' fires in 1939 that burned approximately 65 per cent of Victoria's ash

27 forests.[33] The latest fires were the 'Black Saturday' bushfires in 2009,[34] which caused over 70,000 hectares of ash forest to be burned. One of the expert witnesses called by MyEnvironment in the trial below, Professor Lindenmayer, stated, in a report, that the population of the LBP had potentially been reduced by up to 50 per cent by the 2009 fires, and LBP had not been seen in any of the long-term monitoring sites burned by the 2009 fires.[35]

28 The 2009 fires also had a particularly negative impact on the prevalence of HBT. Professor Lindenmayer gave evidence that 79.4 per cent of 'large living cavity trees' died on sites subject to high-severity wildfire, with between 57 and 100 per cent of large dead trees having been destroyed. He estimated that, as at 2009, between 40 to 50 per cent of potentially suitable habitat for the LBP had been severely damaged by the 2009 fires.[36]

29 The 2009 bushfires also had the effect of increasing the value of the remaining forest as a timber resource because of its scarcity.[37]

30 The second significant threat to the survival of the LBP is timber harvesting.

31 MyEnvironment has, since 2003, campaigned to stop the logging of the habitat of the LBP in the Central Highlands of Victoria. It is an incorporated association having as its chief purpose that of educating and empowering communities to effect change in ensuring the protection of the natural environment in Australia, and encouraging a transition to ecologically sustainable development.

32 VicForests has been vested with the title to the timber resources in the Toolangi coupes under a Timber Release Plan (the 'TRP') and therefore has a legal entitlement to log them, unless restrained.[38] It is a State business corporation within the meaning of the State Owned Enterprises Act 1992, and a public authority. The Order-in-Council establishing VicForests provides that its principal function is 'the management and sale of timber resources in Victorian State forests on a commercial basis',[39] although in so doing it must 'operate in a framework consistent with Victorian Government policy and priorities'.[40] The policies and priorities of the Victorian Government seek to strike a balance between timber production and environmental protection.[41]

33 The statutory context governing the issues raised by the appeal includes four separate pieces of legislation, three of which regulate the management of Victorian State forests and set the conditions under which logging can take place in them. These are the Conservation, Forests and Lands Act 1987 (the 'CFL Act'); the Forests Act 1958; and the Sustainable Forests (Timber) Act 2004 (the 'SFT Act'). The fourth statute, the FFG Act, is concerned with the conservation of endangered Victorian flora and fauna, and relevantly, directs public authorities to have regard to this objective.

34 The CFL Act establishes a legislative framework aimed at the conservation of land, flora and fauna. It provides:[42]

The object of this Act is to set up a legislative framework to enable the Minister -

(a) to be an effective conserver of the State's lands, waters, flora and fauna; and

(b) to make provision for the productive, educational and recreational use of the State's lands, waters, flora and fauna in ways which are environmentally sound, socially just and economically efficient.

35 It establishes that the departmental head of the Department of Sustainability and Environment,[43] the 'Secretary to the Department of Sustainability and Environment' ('the Secretary'), is a body corporate under the control of the Minister.[44] The Secretary has the powers and functions conferred by the Forests Act, the SFT Act, the FFG Act,[45] and other Acts. The CFL Act confers upon the Minister the power, under Pt 5, to make codes of practice that potentially bind persons and corporations engaged in relevant activities. Codes of practice are subject to legislative oversight in that they must be tabled in each House of Parliament for 14 sitting days and are subject to disallowance.[46] Compliance with a code of practice is not required unless the code of practice is incorporated in, or adopted by, either a relevant law or a condition specified in an authority given under a relevant law.[47]

36 The relevant code of practice made under the CFL Act is the Code of Practice for Timber Production 2007 ('the Code'), issued by the Department of Sustainability and Environment in 2007. The Code is a code of practice promulgated under Pt 5 of the CFL Act. It sets out broad guidelines and principles to achieve a balance between timber production and environmental protection, and mandates the production of forest management plans to set out detailed prescriptions for the conservation of native forest fauna. The 'mandatory actions' prescribed by the Code include compliance with measures specified in a relevant action statement made under the FFG Act.[48] In addition, the Code requires that the precautionary principle will apply to decision-making that will impact upon the environment: [49]

Precautionary principle - when contemplating decisions that will affect the environment, the precautionary principle requires careful evaluation of management options to wherever practical avoid serious or irreversible damage to the environment; and to properly assess the risk-weighted consequences of various options. When dealing with threats of serious or irreversible environmental damage, lack of full scientific certainty should not be used as a reason for postponing measures to prevent environmental degradation.[50]

(2) The Forests Act

37 The Forests Act 1958 empowers the Secretary[51] to protect, manage and control State forests. Section 22 requires the preparation of working plans for State forests:

(1) The Secretary -

(a) shall prepare and cause to be put into operation working plans with respect to the control, maintenance, improvement, protection from destruction or damage by fire or otherwise, and removal of forest produce in and from each State forest and any part thereof;

(b) may from time to time revise any such working plan and shall cause the revised working plan to be put into operation; and

(c) forthwith after the preparation or revision of any such working plan shall submit the same to the Minister.

(2) Any such working plan shall specify the detailed plans for the protection of the area from fire and may specify -

(a) the maximum area from which forest produce may be taken annually;

(b) the maximum quantity of forest produce that may be disposed of annually;

(c) the silvicultural operations necessary to ensure the regeneration of the best species of forest trees on areas which have been cut over; and

(d) such other matters as the Secretary considers appropriate.

38 A working plan is defined as a detailed scheme for the control and regulation of the working of a forest or any part thereof and for ensuring the maintenance of a sustained yield of forest produce from such forest.[52] The relevant working plan for the Toolangi coupes is the Central Highlands Forest Management Plan, published in 1998 ('the plan').[53]

39 The need to manage the State's timber resources in a sustainable manner is reflected in the purpose of the SFT Act, which is to provide a 'framework for sustainable forest management and sustainable timber harvesting in State forests'.[54] Section 4 provides that the SFT Act binds the Crown. Part 2 of the SFT Act relates to sustainable forest management. Section 5 sets out the principles of ecologically sustainable development, which are intended to guide sustainable forest management:

(1) In undertaking sustainable forest management in accordance with this Act, regard is to be had to the principles of ecologically sustainable development set out in this section.

(2) Ecologically sustainable development is development that improves the total quality of life, both now and in the future, in a way that maintains the ecological processes on which life depends.

(3) The objectives of ecologically sustainable development are -

(a) to enhance individual and community well-being and welfare by following a path of economic development that safeguards the welfare of future generations;

(b) to provide for equity within and between generations;

(c) to protect biological diversity and maintain essential ecological processes and life-support systems.

(4) The following are to be considered as guiding principles of ecologically sustainable development -

(a) that decision making processes should effectively integrate both long-term and short-term economic, environmental, social and equity considerations;

(b) if there are threats of serious or irreversible environmental damage, lack of full scientific certainty should not be used as a reason for postponing measures to prevent environmental degradation;

(c) the need to consider the global dimension of environmental impacts of actions and policies;

(d) the need to develop a strong, growing and diversified economy which can enhance the capacity for environment protection;

(e) the need to maintain and enhance international competitiveness in an environmentally sound manner;

(f) the need to adopt cost effective and flexible policy instruments such as improved valuation, pricing and incentive mechanisms;

(g) the need to facilitate community involvement in decisions and actions on issues that affect the community.

40 It is apparent from the guiding principle set out in s 5(4)(a) of the SFT Act, as recognised by his Honour,[55] that potentially conflicting economic, environmental, social and equity considerations all need to be weighed up in the context of a decision-making process aimed at ecologically sustainable development.

41 Section 5(4)(b) is a statutory expression of the precautionary principle.

42 The TRP, which provides, amongst other things, for the harvesting and selling of timber resources in the Toolangi coupes, was made under s 37(1), and approved under ss 39 and 40, of the SFT Act. Under s 40(2)(b) of the SFT Act, the Secretary specified conditions with which VicForests must comply when undertaking the activities authorised under the TRP. The significant conditions included compliance with the conditions and standards of the Code; compliance with Management Procedures for timber harvesting, roading and regeneration in Victoria's State forests 2009; and consistency with the plan.[56]

43 Compliance with the Code is also required under s 46(a) of the SFT Act which provides that VicForests must comply with any relevant code of practice relating to timber harvesting.[57]

establish a legal and administrative structure to enable and promote the conservation of Victoria's native flora and fauna and to provide for a choice of procedures which can be used for the conservation, management or control of flora and fauna and the management of potentially threatening processes.[58]

45 A 'potentially threatening process' is defined as 'a process which may have the capability to threaten the survival, abundance or evolutionary development of any taxon or community of flora or fauna'.[59]

46 Section 4(1) of the FFG Act provides for the following 'flora and fauna conservation and management objectives':

(a) to guarantee that all taxa of Victoria's flora and fauna other than the taxa listed in the Excluded List can survive, flourish and retain their potential for evolutionary development in the wild; and

(b) to conserve Victoria's communities of flora and fauna; and

(c) to manage potentially threatening processes; and

(d) to ensure that any use of flora or fauna by humans is sustainable; and

(e) to ensure that the genetic diversity of flora and fauna is maintained; and

(f) to provide programs-

(i) of community education in the conservation of flora and fauna; and

(ii) to encourage co-operative management of flora and fauna through, amongst other things, the entering into of land management co-operative agreements under the Conservation, Forests and Lands Act 1987; and

(iii) of assisting and giving incentives to people, including landholders, to enable flora and fauna to be conserved; and

(g) to encourage the conserving of flora and fauna through co-operative community endeavours.

47 Section 4(2) provides: 'A public authority must be administered so as to have regard to the flora and fauna conservation and management objectives'.

48 As mentioned above, the LBP is listed as a threatened taxon under the FFG Act,[60] having been deemed to be in a demonstrable state of decline which is likely to result in extinction or is significantly prone to future threats which are likely to result in extinction.[61] Section 19(1) of the FFG Act requires the Secretary to prepare an 'action statement' for any listed taxon, or community of flora or fauna, or potentially threatening process as soon as possible after that taxon, community or process is listed. An action statement made under the FFG Act with respect to the LBP has been promulgated, being first published in 1995 and republished in 2003 (the 'LBP AS').[62] A separate action statement has also been promulgated with respect to the loss of HBT as a listed potentially threatening process.[63] The requirements of the LBP AS are a 'mandatory action' under the Code.[64]

49 The LBP AS and the plan are statutory instruments made, respectively, under the FFG Act and the Forests Act. They are both aimed at the conservation of LBP habitat.

50 The LBP AS contains an initial description of the essential habitat for the LBP which emphasises the need for large old hollow trees and the importance of regrowth forests where maximum densities of LBP occur:

The most important components of LBP habitat are nest-tree abundance, vegetation structure and food availability. Large old hollow trees (either dead or alive) for nesting and shelter are essential for the survival of LBP. Maximum population densities occur in regrowth forests (15-50 years) with more than six potential nest-trees per 3 ha and a biomass of Acacia spp. between 20-50% of stand basal area (Smith and Lindenmayer 1992). The term 'potential nest-tree' refers to existing hollow-bearing trees that have the potential to be utilised by the species. LBP prefer short, fat trees with numerous holes and a large quantity of dense surrounding vegetation (Lindenmayer et. al., 1991).[65]

51 It sets out six 'major conservation objectives':

• To guarantee that LBP can survive, flourish and retain their potential for evolutionary development in the wild. In quantitative terms this may be described as to ensure the survival of LBP by managing its forest habitat towards a target of no more than a 1% probability of extinction over 250 years throughout the forest within its current range.
• To identify and take measures to protect all areas of optimum and potentially optimum habitat (as defined in this Action Statement) throughout the known range of the species.
• To apply strategies that address the development of habitat for the future by achieving a long-term balance between the rate of loss of habitat and the rate of formation of habitat.
• To develop modified and alternative silvicultural systems that result in the continuing presence of habitat and still allow for the extraction and production of wood products on an economic basis.
• To undertake research on the biology and ecology of the species with particular emphasis on the risk of wildfire to reduce strategic populations and the dispersal and recolonisation capacities of the species.
• To maintain a stable captive-breeding population of the species for community education and research purposes.[66]

52 It views 'the major challenge' for the LBP's long term conservation as:

the protection and continuing development of old trees with suitable hollows for nesting and shelter, in conjunction with suitable habitat for foraging.[67]

53 The two major threats identified are 'the progression of current favourable habitat to a structurally less-suitable successional stage' and 'the reduction in the number of available nest-trees'.[68] The LBP AS confirms that 'strategies are needed to maintain an adequate number and even distribution of nest-trees in selected areas of regrowth forest and to allow for a proportion of regrowth ... to grow through to ecological maturity (>250 years)'.[69] Several 'key strategies' are described, these being 'the establishment of a reserve system, both permanent and temporary; detailed prescriptions for areas where other management is planned (especially in designated timber production areas); the adoption of alternative silvicultural areas; and continued research and monitoring activities'.[70]

54 In its description of the 'intended management action' required for the long-term conservation of the LBP, the LBP AS addresses the issue of zoning as follows:

• The current zoning system operating in State forest will be revised to reflect the relative long-term stability of some good habitat with living old trees (Zone 1A) and the expected impermanence of other good habitat where most existing hollow-bearing trees are dead and likely to collapse in the near future (Zone 1B). A further zone, Zone 2, will consist of remaining forest, where the prescriptions described under Logging Coupe Planning and Harvesting will be applied to protect existing habitat components for their on-site value and to enhance the value of adjacent habitat.[71]

55 The objectives, definitions and management of the zoning system were to be as follows:

Zone 1A - LBP (and other wildlife) conservation as the main priority.

• mature ash forest (>120 years old) and mixed aged ash forest where the oldest age class is mature (>120 years old).
• regrowth ash forests with at least 12[72] live hollow-bearing trees per 3 ha.
• the minimum area for assessment and establishment of Zone 1A type forest shall be 3 hectares.

Zone 1B - LBP conservation and timber production as joint priorities.

• regrowth ash forest with >12 live or dead hollow-bearing trees per 3 ha combined with a basal area >5m2 of Acacia dealbata, A. obliquinervia or A. frigescens.
• the minimum area for assessment and establishment of Zone 1B type forest shall be 10 hectares.

Zone 2 - Timber production as the major priority, but including the conservation of existing components of habitat.

• regrowth ash forest of varying ages.
• areas with features of Zones 1A, but > a forest that has trees of more than one age cohort on a site and those trees usually have an origin from a different disturbance event, such as a fire. So there may be trees, for example, that date from the mid 1800s and the 1939 fires in the one area on the same stand or the same site.

57 He said that the term 'regrowth forest' means, 'a forest that has regenerated after a particular disturbance event and the forest is largely of one age'. Being of one age would not preclude there remaining in that forest some of the old growth sufficient to constitute HBT. This would suggest that there is overlap between a mixed age ash forest and regrowth forest.[74] Moreover, as discussed below, it is noteworthy that the regrowth forest from the 1939 bushfires would not start to develop Zone 1A characteristics across the forest for another 50 to 100 years.[75]

58 One of the issues of dispute at the trial, and on the appeal, was the relationship between the first and second dot points in the definition of Zone 1A. The second dot point makes no reference to age and the question arose as to whether it stands alone as a criterion of habitat to be protected in Zone 1A or whether it forms a sub-set of the mixed age ash forest referred to in the second category of the first dot point.

59 The general aims in managing the Central Highlands State forests are stated in the plan as follows:

• In combination with all public land, viable populations of native species and ecosystems are maintained in a structurally diverse forest with increased area of older-aged forest, particularly the ash-eucalypt species.
• A sustainable resource base for forest-dependent industries is maintained.
• The scale and pattern of timber harvesting more closely follows the scale and pattern of natural disturbances.
• The quality of water flowing from the forest is maintained.
• Cultural values are maintained.
• Changing community expectations and an expanding knowledge of the forest ecosystem are incorporated into forest policy and management practices.[76]

60 VicForests relies on these various aims to support its contention that the plan seeks to achieve a balance which is concerned not only with the preservation of LBP habitat, but also with wider concepts of management of forest resources.

61 By contrast, MyEnvironment points to the specific aim directed at 'Biodiversity Conservation', described as a 'key aim of forest management'[77] which states:

AIM

To ensure that all indigenous plant and animal species and communities survive and flourish throughout the Central Highlands.[78]

MyEnvironment also points to the biodiversity conservation strategies set out immediately preceding this stated aim:

• the protection of a significant proportion of all vegetation classes across all public land tenures
• the maintenance and creation of a mosaic of forest growth stages within a managed environment which includes natural and human induced disturbances
• specific conservation measures for known rare or threatened species to maintain species and genetic diversity.[79]

62 The obligation under the FFG Act is to 'guarantee that all taxa of Victoria's flora and fauna can survive, flourish and retain their potential for evolutionary development in the wild',[80] the plan stating that:

This plan, coupled with Action Statements issued under the FFG Act, is the primary plan for implementation of Victoria's Biodiversity Strategy in the Central Highland State forests.[81]

63 Under the plan, forest management is undertaken by the application of 'management guidelines', 'management prescriptions' and 'management actions', which 'establish a framework for the future management of the forests and commit the [Government Department[82]] to the completion of specific management actions which will enhance the conservation and production roles of State forest'.[83] These are described as follows:

• Management Guidelines give direction to forest managers to facilitate protection or careful management of specific values or uses.
• Management Prescriptions detail specific conditions or standards which are to apply to forest operations in the vicinity of certain threatened flora or fauna. More detailed prescriptions are established at the local level and are reflected in Wood Utilisation Plans.
• Management Actions commit the [Government Department] to implementing a number of actions which will further enhance the management of State forest.[84]

64 Consistently with the Code, the plan makes provision for the establishment of three forest management zones to achieve its aims, providing different degrees of protection. This system of zones is designed to set the priorities and permitted uses for different parts of the forest. The three zones are described as follows:[85]

• Special Protection Zone (SPZ) will be managed for conservation, and timber harvesting will be excluded. This zone forms a network designed to link and complement established conservation reserves; [86]
• Special Management Zone (SMZ) will be managed to conserve specific features, while catering for timber production under certain conditions;
• General Management Zone (GMZ) will be managed for a range of uses, but timber production will have a high priority. Unproductive forest (less than 28m mean stand height) is included in the GMZ.

65 The SPZ has largely been created around old-growth forest, habitat for various species of owl and for the LBP, representative examples of 'Ecological Vegetation Classes', areas of rainforest and associated buffers, and reserves for Tall Astelia.[87] As stated in the plan, the total area protected as LBP habitat by SPZ in the Central Highlands Forest Management Area is 27,001 hectares.[88] It is linked by natural feature zones, linear reserves of a minimum 200 m width, protected streams and rainforest with buffer zones, and walking tracks. The SPZ is managed to minimise disturbances or processes that threaten conservation values, and timber harvesting is excluded.[89]

66 This is in contrast to the SMZ which contains areas of high landscape value that require modification to timber harvesting and other land use practices, but from which timber and other forest produce may be harvested, as long as that harvesting adequately addresses the protection and conservation of the identified value in the zone. The SPZ also stands in contrast to the GMZ, the forest in which is to be managed for the sustainable production of sawlogs in accordance with the Code and any relevant management prescriptions. The GMZ is divided into two sub-zones of forest: forest in the 'timber production subzone' which is used to produce sawlogs on a sustainable basis in accordance with the Code, and forest in the 'other uses subzone' which is used to conserve drier forest types, as well as for fuel-reduction burning, harvesting of other forest produce and recreation.[90]

67 Chapter 3 of the plan contains a zoning definition for three zones of LBP's habitat warranting different forms of protection, Zone 1A, Zone 1B, and Zone 2. The definitions are first set out in descriptive form. This is followed by a summary of the description in a table. It is the construction of the zoning definition for Zone 1A habitat that was the focus of the appeal.

Habitat Classification and Management

The Flora and Fauna Guarantee Action Statement which has been prepared for the species (CNR 1995b) defines the three zones of Leadbeater's Possum habitat.

1. Zone 1A habitat contains living older trees and is expected to be important for the long-term conservation of the species. Zone 1A habitat is protected in either conservation reserves or the SPZ. Appendix L indicates the extent of existing LBP Zone 1A habitat and ash-eucalypt forest across its known range.
2. Zone 1B habitat currently contains good habitat, but most of the existing HBT are dead and are likely to collapse in the near future. Zone 1B habitat in the GMZ is excluded from timber harvesting until either of the Zone 1B habitat attributes (the presence of dead mature or senescing trees, or wattle understorey) no longer exist.

3. Zone 2 habitat consists of the remaining ash-eucalypt forests.

Table 3.2 Leadbeater's Possum habitat Zones

>12 per 3 ha in patches greater than 3 ha[91]

General Management Zone but excluded from timber harvesting while Zone 1B attributes remain.

Regrowth ash forest of varying ages; or areas with features of Zone 1A or Zone 1B but > This plan retains patches of ash-eucalypt forest totalling at least 600 ha in 15 of the 21 LMUs. Many of the retained patches include existing Zone 1A habitat. Ash-eucalypt forest in the six remaining LMUs is primarily 1939 regrowth. This forest will not start to develop Zone 1A habitat characteristics for another 50 to 100 years. By the year 2100, at least 45% of the total area of ash-eucalypt forest in the Central Highlands will be over 150 years old (see Figure 3.1). This future relative abundance of suitable habitat provides a significant opportunity to adapt the system of retained habitat for Leadbeater's Possum to future management requirements.[95]

71 The Management Prescription for LBP in Zone 1A of the plan, set out below,[96] refers to 'living mature and senescing trees'.

72 The description of Zone 1B habitat in Table 3.2 refers to 'dead mature or senescing trees'.

73 There was evidence at the trial that, in this context, a 'mature tree' would be 'something greater than 120 years of age' while a senescing tree 'is a tree that's gone

73 past its maturity and is starting to decay substantially'.[97] A forest scientist, called by VicForests, Michael Ryan, explained:

[W]hen a tree's mature the senescing part is when it's really starting to fall apart effectively and we are talking about trees in the far later stages of its life ... .

74 The plan identified regrowth, mature (including younger mature and older mature), and senescent stages of canopy trees largely based on the description of growth characteristics of canopy trees by Jacobs, Growth Habits of the Eucalypts:[98]

75 Seven forms of tree from maturity (form 1) to increasing stages of senescence were identified by Professor Lindenmayer in a paper he wrote in 1988:[99]

Fig. 1. The seven forms and four groups used for subjective classification of potential nest trees (all trees ≥ 0.5 m dbh and ≥ 6 m height) in ash forest on the basis of increasing senescence, branch loss, and windthrow of the main stem.

76 The 1988 report refers to potential nest trees. A potential nest tree ('PNT') is any tree which is more than 0.5 metres in diameter and more than 6 metres in height, which contained obvious hollows.[100] Hollows are formed by reason of 'natural branch shredding and damage by wind, lightning, fungi and wood-boring insects, particularly termites'.[101] All of the PNT surveyed at each site investigated for the purposes of preparing the 1988 report were described by four variables: (1) height; (2) diameter at breast height ('dbh'); (3) number of fissures; and (4) access to surrounding vegetation; and by one attribute, namely, tree form. None of the seven tree forms of PNT represented immature trees. A subsequent diagram used in a 1991 paper prepared by Professor Lindenmayer included an eighth form, that of a hollow dead stump:[102]

Fig. 2. Classification of forms of hollow-bearing trees: 1, mature, living tree; 2, mature living tree with a dead or broken top; 3, dead tree with most branches still intact; 4, dead tree with 0-25% of the top broken off; branches remaining as stubs only; 5, dead tree with the top 25-50% broken away; 6, dead tree with the top 50-75% broken away; 7, solid, dead tree with ≥75% of the top broken away; 8, hollow stump.

77 The plan then sets out, by reference to Table 3.2, the following 'Management Prescription' for LBP habitat zoning:

MANAGEMENT PRESCRIPTION

Leadbeater's Possum

• Include Leadbeater's Possum Zone 1A habitat (living mature and senescing trees - see Table 3.2) in the SPZ.
• Exclude Zone 1B habitat from harvesting until either of the Zone 1B habitat attributes (the presence of dead mature or senescent trees, or wattle understorey) no longer exist.
• On completion of the modelling of the suitability of forest for Leadbeater's Possum habitat, review the adequacy of the retained habitat system established in this plan.[103]

78 In dismissing MyEnvironment's application for a permanent injunction to restrain the resumption of logging in the Gun Barrel coupe, his Honour held that:

(a) the LBP AS describes Zone 1A habitat as applying a density factor to mature HBT;

(b) the LBP AS contemplates that the exclusion zone scheme is to be implemented through the plan, and it is the plan which crystallises the zone requirements;

(c) the plan applies the relevant density factor to mature or senescing trees.[104]

79 Thus, he held that the criteria for inclusion in Zone 1A habitat depended upon the required density of mature or senescing HBT. It is this disjunctive construction of the zoning definition of Zone 1A habitat, as requiring a certain density of either mature or senescing HBT, that is challenged by VicForests in its Notice of Contention.

80 The three individual conclusions can be referred to, respectively, as the conclusion on the construction of the LBP AS; the conclusion on the inter-dependence of LBP AS and the plan; and the conclusion on the construction of the plan.

81 His Honour also held that the logging of the Toolangi coupes would not breach the precautionary principle.

(1) The conclusion on the construction of the LBP AS

82 The trial judge concluded that the prescription in the second dot point of the description of Zone 1A habitat in the LBP AS,[105] consisting of regrowth ash forest with at least 12 live HBT per 3 hectares, relates to mature trees (more than 120 years old) when the minimum area for assessment and establishment of Zone 1A forest is 3 hectares.[106] That is, the second dot point of the Zone 1A management action relates to old living HBT.[107]

83 He based his conclusion upon the following seven indicia:[108]

(i) the initial description of essential habitat which relates to large old HBT;

(ii) the initial description of optimum habitat which includes trees with the present potential to be used as nest trees (that is, large old HBT);

(iii) the statement of the relevant conservation management objective as identifying and taking measures to protect all areas of optimum and potentially optimum habitat;

(iv) the identification of the major challenge for long term conservation of the LBP as the protection and continuing development of old trees with suitable hollows for nesting and shelter;

(v) the discussion of ecological issues specific to the taxon which identifies the need for old growth montane ash forest trees as an element of LBP habitat;

(vi) the endorsement of changed timber harvesting practices away from clear felling in order to create a long term supply of old aged trees; and

(vii) the rationale for the previous guideline stated in the Draft Strategies and Guideline which referred to multi-age structured forest where the latter contains more than 12 living, emergent PNT per 3 hectares.

84 The first indicia, the initial description of 'essential habitat' in the LBP AS, as set out above,[109] emphasised the need for 'large old hollow trees (either dead or alive) for nesting and shelter [as] ... essential for the survival' of the LBP.

85 The second indicia, the initial description of 'optimum habitat' in the LBP AS, where the maximum population densities occur, consisted of regrowth forests with more than six PNT per 3 hectares.[110] As 'potential' was to be understood as referring to present as opposed to future potential, his Honour held that this had the consequence that the PNT must be large old HBT.[111] What was significant was the preservation of mature HBT within regrowth forests.[112]

86 The initial descriptions of essential habitat and optimum habitat in the LBP AS were accompanied by a reference to the 1991 paper authored by Professor Lindenmayer.[113] The judge noted that the article concluded that the continuation of an 80 to 120 year long interval between logging operations would 'result in trees being harvested well before they develop characteristics which make them suitable as nest sites for arboreal animals'.[114] He also noted that Professor Lindenmayer's first report relied on by MyEnvironment stated that montane ash trees are typically 120 years old before hollows regularly begin to appear[115] and that the large hollows which are typically used by arboreal marsupials typically take 150 to 190 years to first appear and persist up until the end of the tree's life (400 to 500 years) and continue to persist in a dead tree for up to another 70 years as long as that tree remains standing.[116]

87 The third indicia was supported by the objective identified in the LBP AS[117] as the aim of preserving optimum and potentially optimum habitat which, as described in the LBP AS, occurred primarily in regrowth forests. The 'Reasons for Conservation Status' described in the LBP AS stated that: 'It is in ... regrowth forests where the highest densities of [LBP] may now occur'.[118] Those regrowth forests included the 1939 regrowth forests and, as mentioned above, the area for retained habitat described in the plan indicated that the 1939 regrowth forest 'will not start to develop Zone 1A habitat characteristics for another 50 to 100 years'.[119] Thus, the judge considered that it was the preservation of mature HBT within regrowth forests that was significant to the conservation of the LBP.

88 It was accepted by Professor Lindenmayer, in cross-examination, that the Gun Barrel coupe consists predominantly of 1939 regrowth. He also said that he would not expect 1939 regrowth, now about 73 years old, typically to develop hollows for another 50 years.

89 The fourth indicia lay in the manner in which the LBP AS described 'the major challenge' for the preservation of LBP, set out above,[120] which specifically identified 'old trees' with suitable hollows as that which needed to be protected and developed.

90 The judge also considered, as the fifth indicia, the Population Viability Analysis undertaken by Lindenmayer and Possingham in 1994[121] which predicted a 'higher probability of persistence' of LBP in areas that 'were characterised by larger patches of old growth forest'.[122] In its discussion of ecological issues specific to the taxon of LBP, the LBP AS stated:

On the basis of this work, the authors strongly recommend that a key forest wildlife management objective must be to grow areas of existing regrowth forest through to ecological maturity or old-growth status (i.e. 250 years). ... these regrowth forests require >150 years of growth before fire can effectively create the necessary floristics and structural diversity critical for [LBP].[123]

91 The judge considered that the last sentence of the passage quoted demonstrated the relationship between regrowth forest and HBT in a manner which recognised the significance of old HBT by indicating that regrowth forests require more then 150 years of growth before they have the characteristics critical for LBP habitat.[124]

92 The sixth indicia was based upon the recognition in the LBP AS that clear felling should be avoided. Clear felling involves the removal of all merchantable trees at one felling, followed by seedbed preparation by either burning or mechanical disturbance, and artificial sowing or planting leaving large dead and live old trees of standing on the coupe unless they present an unacceptable safety hazard or are chosen for seed collection. Relevantly, clear felling has the problem that the length of the rotation, 80 years, does not allow trees to grow large enough on harvested areas for hollow formation to commence. The LBP AS recognised that:

the current system of harvesting and regenerating ash forests is clear felling ... the current system is planned to operate on a nominal 80-year rotation, which leaves no allowance for any trees on logging coupes to grow to ecological maturity and thus develop hollows for future use.[125]

It went on to say:

The nominal rotation length of 80 years does not allow trees to grow large enough on harvested areas for hollow formation to begin, let alone develop sufficiently for [LBP] to use. ... It thus appears, that, to properly cater for [LBP], rotation times should be well in excess of 200 years. However, by that age trees would have senesced and be well beyond optimum harvest age ... strategies are needed to maintain an adequate number and even distribution of nest-trees in selected areas of regrowth forest and to allow for a proportion of regrowth, either as individual trees or complete stands of forest, to grow through to ecological maturity (>250 years).

93 The seventh indicia was drawn from the previous management action referred to in the LBP AS as the Draft Management Strategies for the Conservation of LBP, endorsed in 1991, which had been progressively implemented. The creation of zones was one such strategy. In referring to these earlier strategies the LBP AS said that it was montane ash trees older than 120 years that are protected:

These include the establishment of a zoning system with specific prescriptions designed to protect and develop habitat for the species. Such prescriptions address assessment procedures, logging coupe size and shape, buffer establishment and the protection of all [HBT] regardless of zoning classification. The last prescription means that all montane ash trees older than 120 years are protected within the known distribution of [LBP].[126]

94 In approaching the language ultimately used to describe Zone 1A in the LBP AS, the judge looked first at the previous 1991 Draft Strategies and Guidelines[127] which, while providing for three zones (Zones 1 to 3), had set out the requirements for Zone 1 without reference to the age of the HBT:

Zone 1. [LBP] (and other wildlife) conservation as the major priority. Consisting of all areas of mature ash forest (>120 years old) and regrowth ash forest with >12 live or dead [HBT] per 3 ha.

95 The LBP AS made it plain that it sought to revise the previous zoning arrangements by amending the most stringent zone from Zone 1 to Zone 1A and linking it to 'living old trees' in its 'intended management action' described above:[128]

The current zoning system operating in State forest will be revised to reflect the relative long-term stability of some good habitat with living old trees (Zone 1A) and the expected impermanence of other good habitat where most existing [HBT] are dead and likely to collapse in the near future (Zone 1B).[129]

96 The judge considered that the purpose of the revision was to refine the previous zoning arrangements to include within the relevant category of live trees in Zone 1A only those HBT that were 'old'.[130] That purpose was reflected in the category of HBT in regrowth forest to which Zone 1A is directed.

97 The judge focused upon the requirements in the zoning system ultimately endorsed in the LBP AS and made these observations about the alternative constructions of Zone 1A in the LBP AS:[131]

• Neither the word 'or' nor the word 'and' appears at the end of the first dot point - however, the three dot points must be read cumulatively to some extent because the third dot point relates to the first and second;[132]

• The term 'regrowth ash forest' in the second dot point is not used in contradistinction to 'mixed aged ash forest' in the first dot point because 'mixed aged forest where the oldest age class is mature necessarily means forest which comprises regrowth mixed with mature trees, because trees younger than mature are regrowth';[133]

• The first dot point expressly refers to trees more than 120 years old while the second dot point makes no reference to age - this supports the view that the second dot point refers to a different category[134] - however:

(a) if the second dot point did not qualify or explicate the second category in the first dot point, the forest identified in the second category of the first dot point (mixed age ash forest where the oldest class is mature) would qualify regardless of whether any of the trees were HBT - 'a patch of regrowth forest containing some mature trees is a patch of mixed aged forest containing trees of the specified class'[135] and yet this would be sufficient to be included within the most stringently protected habitat of the LBP, Zone 1A, irrespective of whether those trees contained hollows which the LBP need for nesting and shelter;

(b) if the second dot point is read as a separate category, it would not be limited to montane ash forests - a regrowth ash forest

of any species, of any age, would qualify providing it included 12 live HBT per 3 hectares.[136]

98 His Honour considered that the provisions of the LBP AS that related to planning and harvesting also supported the conclusion that the Zone 1A provisions in respect of HBT are intended to relate to old HBT:

• Buffer strips of unlogged forest were proposed which 'should be allowed to grow to ecological maturity (at least 250 years old) and thereby provide [HBT] for [LBP] and other hollow-dependent wildlife';[137]

• Currently living nest trees were described as commanding special attention because even after fire they would still provide PNT for LBP and HBT should not be felled for seed collection;[138]

• Forest in the reserve system was to be 'allowed to grow to maturity' to provide habitat to replace Zone 1A and Zone 1B.[139]

99 The judge further considered three scientific papers on the LBP published by Professor Lindenmayer and others, the 1988 report,[140] the 1991 paper,[141] and a paper in 1993,[142] all of which informed the LBP AS. He noted that the evidence of Professor Linenmayer was that he used the term 'HBT', which he originated in his doctoral thesis,[143] to refer to all trees with an obvious hollow or cavity, excluding seedlings or small saplings, and that he had based his survey methodology on the premise for almost 30 years. However, the judge concluded that although Professor Lindenmayer's survey methodology had been based on the abundance of HBT in the general sense, the 1988 report, the 1991 paper and the 1993 paper distinguish between the significance of large old HBT and other HBT, and do so expressly in the context of zoning requirements.[144] He held that the papers demonstrated:

(a) That field survey work undertaken by Prof. Lindenmayer has adopted the same standard for [PNT], [HBT] and 'trees with cavities'. The definition is a broad one expressed by reference to minimum dimensions and the presence of cavities.

(b) The papers clearly identify the critical role of large old trees as habitat for the LBP.

(c) The field survey work directly utilises the criteria of senescence and classifies the trees surveyed expressly by categories of senescence.

(d) There is a sensible basis in the words of the 1993 paper for adopting a conservation strategy which excludes areas from timber production that contain 'numerous veteran trees with cavities'.

(e) Both the LBP AS and the FMP [the plan] may be regarded as responsive to the research described in the papers, if the zone management actions and management prescriptions they contain are read as relating to old, ie mature and senescent, montane ash trees.

(f) The LBP AS and the FMP [the plan] reflect the scientific research by endorsing practices other than clear felling as having significant potential benefit for the long term supply of [PNT].[145]

100 In particular, the 1988 report, which described the seven stages reflecting the passage of mature trees through subsequent stages of senescence referred to above,[146] identified preferred living trees as those with dead or broken tops (form 2),

heights in excess of 46 metres and dbh[147] in excess of 2.1 metres.[148] The 1988 report made reference to an earlier paper by Ashton in 1976 who had published a relationship between dbh and age for mountain ash 'which predicts a period of 190 years at 2.1 m dbh, before trees develop hollows suitable for [LBP]'.[149] Another study 'suggest[ed] a similar, but approximately 20% slower, growth rate for shining gum'.[150] The 1988 report went on to say:

[LBP] does not appear to favour use of living mature trees until the trees have >2 m dbh (approximately 200+ years of age).[151]

101 Preferred dead trees were those with increasing senescence, a height of 16 to 25 metres; a diameter of 1.1 to 2.5 metres; and good access below 30 metres height. The 1991 paper, which identified an additional eighth stage of senescence,[152] went on to say that the preference of LBP for HBT was for short fat trees, that is, those HBT in the late stages of senescence (forms 7 and 8):

The preference of G. leadbeateri for short, fat trees with a large number of holes and a high access score tends to set this species apart from any of the others. ... the short, fat trees required by G. leadbeateri ... were typically those in the late stages of decay (forms 7-8), although there were also several trees belonging to form 2. Preference by the species for these trees as den sites means they are likely to be considerably older than the minimum of 190-220 years suggested by Smith et al. (1985) and Smith and Lindenmayer (1988).[153]

102 His Honour observed that the 1991 paper made recommendations to secure an on-going supply of a substantial number of trees in each stage of senescence 'on the express premise that ash trees do not develop hollows that are suitable for occupation by wildlife until they are at least 120 years of age'.[154] This was not to deny that trees can develop hollows when they are younger than 120 years, although they are less likely to do so. The judge accepted that an individual tree may develop hollows before reaching 120 years;[155] what he rejected was the notion that the management action chosen to protect the optimal, and potentially optimal, habitat of the LBP was affected by the physical possibility of a tree developing hollows before maturity. The existence of the possibility of cavities developing before maturity did not diminish the strategy of protecting those parts of a forest that exhibited the characteristics most likely to provide breeding spaces for LBP.[156]

103 The 1993 paper demonstrated that the abundance of holes, fissues and hollow branches increased with tree diameter.[157] Moreover, it showed a relationship between larger older trees and number of holes.[158] It also indicated a relationship between different stages of senescence and the presence of cavities and reaffirmed that the type of nest tree preferred by many species in montane ash forest generally takes several hundred years to develop.[159] With respect to regrowth forest, it indicated that large old trees in regrowth forest typically have a larger number of hollows than old trees in mature forests because they are likely to have undergone the disturbances of fire and logging. It is those disturbances which both give rise to the regrowth and facilitate the development of cavities in the resulting stem damage:

Trees with cavities remaining in stands of young forest contained more cavities than those in areas dominated by older vegetation. ... in many cases, large old trees in younger regrowth forest are likely to have suffered the impacts of more disturbances than stems with similar attributes (e.g. diameter, height and form) located in older stands of ash-type forest. This would, in turn, provide a greater opportunity for stem damage and the formation of cavities.[160]

104 The scientific papers thus provided substantial support for identifying regrowth forest with at least 12 old HBT per 3 hectares as the area of LBP habitat warranting the greatest protection, that of allocation to Zone 1A. Moreover, such forest fitted the description of 'mixed age ash forest where the oldest age class is mature'.

105 The judge also considered the force of the separate action statement for HBT[161] which confirmed (1) the development of large hollows as a characteristic feature of tree senescence and (2) that HBT are usually the oldest and largest trees within their communities.[162]

106 Finally, having expressed his preferred view, his Honour was prepared to acknowledge that the construction of Zone 1A proffered by My Environment was nevertheless 'open'.[163] However, he concluded that it ought be rejected on the ground that other provisions of the LBP AS, especially those requiring reserves for LMUs,[164] showed that its aim was not the protection of all Zone 1A habitat as necessarily indispensable, but that a target for the provision of Zone 1A habitat would be arrived at, once the actual extent and spatial distribution of Zone 1A (and Zone 1B) habitat was known.[165] It would appear that his Honour took this to suggest that the measures recommended by the LBP AS to protect optimum and potentially optimum LBP habitat expressly recognised that some forest containing old living HBT might not be excluded from logging; that providing there was 'a continuing supply of habitat at appropriate levels and distribution to enable [LBP] to thrive throughout its range in State forest', even forest which contained the required density of old living HBT might not be fully protected. It followed that it was even more likely that areas of forest which contained fewer LBP nesting and roosting sites, because the HBT therein were young and did not have the diameter or the senescence to develop the number of cavities typically found in living old HBT, were not to be allocated to Zone 1A.

107 His Honour then turned to the issue of the implementation of the LBP AS.

(2) The conclusion on the inter-dependence of the LBP AS and the plan

108 The LBP AS provides that the primary vehicle for the implementation of action statements made under the FFG Act, with respect to State forest, are forest management plans prepared in accordance with the Code. It states:

The Timber Industry Strategy (Victorian Government 1986) sets directions for the timber industry by outlining a balance between timber production and environmental protection. Broad guidelines and principles to achieve this balance have been developed in the Code of Forest Practices for Timber Production (CFL 1989). A requirement of this 'Code' is the production of Forest Management Plans (FMPs) which include detailed prescriptions for the conservation of native forest fauna. In State forest, FMPs are the primary vehicles for the implementation of Flora and Fauna Guarantee Action Statements.[166]

109 Moreover, in the discussion of the implementation, evaluation and review of the LBP AS, there is an express acknowledgement that the LBP AS will provide guidance but that the management of the forest will be resolved by specific forest management plans:

This Action Statement will be implemented by planning and operational staff from the relevant Areas of the Department of Conservation and Natural Resources. Whilst the Intended Management Actions will provide the necessary directions and options for the conservation of Leadbeater's Possum, the management of the forest estate will be determined by relevant area management plans which take into account economic, social and other environmental considerations. Intended actions in this Statement should be incorporated in forest management plans, forest coupe plans, park and reserve management plans, plans for the management of closed water catchments and captive management plans.[167]

110 The judge considered that these passages made it clear that it is for forest management plans to 'crystallise and "determine" the prescriptions governing Zone 1A'.[168]

111 The separate HBT AS also acknowledged that 'the application of management guidelines, including forest management zones and prescriptions, for fauna species [was] as provided in Forest Management Plans (eg [LBP] Special Protection Zones and prescriptions)'.[169]

112 The judge concluded that a measure specified in the LBP AS was a 'direction and option' to be given prescriptive form and effect through the plan. He reasoned:

In summary, I accept MyEnvironment's submission that the Code picks up and applies 'measures specified in relevant Action Statements'. In turn, as this Court held in the Brown Mountain case,[170] it is potentially possible to identify specific operational requirements in ASs. Nevertheless, in the present case, the LBP AS itself contemplates that the relevant specification will be contained in the FMP [the plan]. Furthermore, the remedial nature of the LBP AS does not affect the mechanism it adopts for implementation.[171]

113 Furthermore, the fact that the terms of the LBP AS themselves subordinate the relevant management action to the plan precluded any reliance on cl 1.4.9(a) of the Management Procedures made under the Code which direct that priority be given to the last published standard, despite the republication of the LBP AS in 2003.[172]

114 The judge inferred that it followed that the LBP AS does not impose a Zone 1A obligation independently of the plan.[173] This was barely challenged on the appeal.

115 This left the construction of the plan to be determined.

(3) The conclusion on the construction of the plan

116 The judge's focus in his construction of the plan was on the description it contained of the 'Habitat Classification and Management' of the LBP and the zoning definitions found in Table 3.2.[174]

117 He found that the HBT with which Zone 1A is concerned are 'living mature and senescing trees'.[175] He drew significance from the following observations about the plan:

(1) there is specific reference to trees of mature and senescent growth stages as generally containing more hollows than regrowth trees;

(2) in turn, there is an identified need to provide for replacement of old HBT in and around logging coupes;

(3) it is predicted that there will be a steady decline of HBT until about 2065 due to the post-1939 forest composition in the Central Highlands;

(4) the plan adopts a precautionary approach to maintaining hollow-dependent wildlife populations in state forest. At the strategic scale, large areas of forest containing mature and senescent trees are protected within the SPZ. In addition, it is proposed to consider further the configuration of retained areas of vegetation and future timber harvesting coupes at sub-catchment level;

(5) HBT are protected by inclusion in areas within which timber harvesting is excluded and by the application of the guideline within timber harvesting coupes;

(6) The management guideline requires retention of pre-1900 trees, emphasising the connection between maturity and HBT;

(7) The guideline envisages the retention of HBT (where present) and potential HBT as a proportion of the individual trees harvested in ash-eucalypt forest originating since 1900.[176]

118 In reaching his conclusion, he had regard to the reference to 'living older trees' in the description of Zone 1A preceding Table 3.2[177] which rendered it difficult to read Zone 1A in Table 3.2 as being directed to any HBT regardless of age; the statement that 1939 regrowth forest will not start to develop Zone 1A habitat characteristics for about another 50 to 100 years;[178] and the need to give effect to the words in the Management Prescription: 'Include [LBP] Zone 1A habitat (living mature and senescing trees - see Table 3.2) in the SPZ', [179] which he considered put the issue 'beyond dispute'.[180]

119 He rejected the submission of MyEnvironment that the words 'living mature and senescing' simply illustrate the type of trees which are commonly HBT, or that they are to be understood as a guide or indicator of the kinds of trees which 'often' meet the definition of HBT.[181] The plan is intended to be utilised by foresters and, as such, the words 'living mature or senescing' were to be treated as indicating the ambit of the prescription. He further rejected the submission that the words of the prescription are to be subordinated to the words 'living trees containing hollows' appearing in Table 3.2.[182]

120 He observed that there were some other inconsistencies in language between, on the one hand, the description preceding Table 3.2 and the Management Prescription, and, on the other hand, the summary in Table 3.2. For example, the preceding description of Zone 1B, immediately before Table 3.2, includes, in the identification of Zone 1B habitat attributes, 'the presence of dead mature or senescing trees'. So too the Management Prescription describes the 'Zone 1B attributes' as 'the presence of dead mature or senescent trees'. (This stands in parallel to the express terms of the prescription for Zone 1A attributes, namely, 'living mature and senescing trees').[183] Yet the words 'mature or senescent' do not appear in the summary table; Table 3.2 points to Zone 1B as simply, 'dead or living trees containing hollows'. The judge inferred that the summary in Table 3.2 for Zone 1B attributes cannot be satisfactorily read as overriding the express terms of the Management Prescription.

121 The judge also highlighted the absence in the description of Zone 1A in Table 3.2 of any reference to 'mature ash forest', the first category in the first dot point of the LBP AS description of Zone 1A.[184] This meant that if Zone 1A habitat in the plan did not require that the HBT be 'mature and senescing' (as MyEnvironment contended) there would be no relevant reference to mature forest or mature trees whatsoever in the zone provisions of the plan. This was an absurd consequence of MyEnvironment's construction.

122 The judge also rejected MyEnvironment's submission that the terms 'mature' and 'senescing' were so uncertain as to be meaningless.[185] They clearly had a well-understood meaning for foresters, based upon the form of the crown assessed, which accorded with that articulated by Jacobs, as referred to above.[186] The terms were used by the plan for the purpose of classifying forest stages reflecting that usage and were 'capable of ready practical application on the ground'.[187]

123 The judge ultimately inferred that the two definitions of Zone 1A habitat appearing under the heading 'Habitat Classification and Management' in the plan, the description preceding Table 3.2, and in Table 3.2 itself,[188] must both be read subject to the Management Prescription[189] which qualifies those definitions by stipulating that Zone 1A habitat consists in living, mature and senescing trees.[190]

(4) Requirements of maturity and senescing - disjunctive or conjunctive?

124 An issue was raised at trial, and became the subject of the Notice of Contention on the appeal, as to whether the prescription under the plan for Zone 1A habitat required that the HBT be both mature and senescing or, alternatively, only mature or senescing. That is, should the expression 'mature and senescing' in the Management Prescription[191] be read conjunctively or disjunctively?

125 It was conceded by VicForests at trial, and established on the evidence, that a senescing tree of the relevant species is necessarily one which has previously been mature.[192] The judge relied on this fact to conclude that the prescription under the plan for Zone 1A habitat relates to HBT which are either mature or senescing. He considered that unless read disjunctively the word 'mature' would be superfluous and the prescription could have been confined to trees that are 'senescing'.

(5) The application to VicForests' variable retention harvesting proposal

126 His Honour observed that the further logging of Gun Barrel, in accordance with the variable retention harvesting proposed by VicForests, would not breach the relevant control, the exclusion of logging in the Zone 1A habitat, if he were to find (as he did find) that the criteria for that control required a specified number of mature or senescing HBT but that, conversely, further logging of Gun Barrel would breach the control if the control applied to all montane ash HBT regardless of age.[193]

127 Having found that the criteria for the relevant control depended upon there being a density of 12 mature or senescing HBT in patches greater than 3 hectares (or, equivalently, a density of greater than 4 mature or senescing HBT per hectare in an area greater than 3 hectares)[194] meant that MyEnvironment had not established that the proposed variable retention harvesting of Gun Barrel would breach the Zone 1A provisions of the plan. This was because the density requirement for Zone 1A habitat under the plan was not satisfied in the Gun Barrel coupe.[195] Moreover, although the Freddo and South Col coupes might contain Zone 1A habitat,[196] this had not been ascertained,[197] and the proposals for their harvesting had not sufficiently crystallised to support a conclusion that they would breach the Zone 1A prescription.[198]

128 Variable retention harvesting stands in contrast to clear felling and involves leaving islands of retained habitat.

129 The Gun Barrel Variable Retention Plan proposed by VicForests is shown below:[199]

130 The parts of the Gun Barrel Variable Retention Plan that are coloured yellow and pink are both protected from timber harvesting. Those parts coloured yellow are islands of retained habitat; those parts coloured pink form part of an SPZ. There is a 'snig track' passing through the yellow area which was created in accordance with the plan. Timber harvesting would occur within the areas shaded green, subject to existing prescriptions within the plan, such as the retention of pre-1900 trees.

131 The orders made by his Honour had the effect of permitting the Gun Barrel Variable Retention Plan to proceed. The area proposed to be harvested was 13.7 hectares which is about .0075 per cent of the total area of the ash eucalypt forest in the Central Highlands.[200]

132 The Notice of Appeal filed by MyEnvironment identified six grounds of appeal:[201]

1. His Honour erred in holding that the LBP AS did not impose obligations on VicForests in relation to Zone 1A habitat (as defined in the LBP AS) independently of the plan. His Honour should have found that, on its proper construction, the LBP AS imposed enforceable obligations on VicForests in relation to Zone 1A habitat (as defined in the LBP AS) independently of the plan.

2. His Honour erred in holding that the proper construction of the prescription in the LBP AS concerning Zone 1A habitat is that the prescription relating to regrowth ash forest with at least 12 live HBT per 3 hectacres relates to mature trees (more than 120 years old) where the minimum area for assessment and establishment of Zone 1A forest is 3 hectares. His Honour should have found that, on its proper construction, the prescription in the LBP AS concerning Zone 1A means mature ash forest (>120 years old) and mixed ash forest where the oldest age class is mature (> 120 years old), or regrowth ash forests with at least 12 live HBT (regardless of age) per 3 hectares, where the minimum area for assessment and establishment of Zone 1A Type forest shall be 3 hectares.

3. His Honour erred in holding that the proper construction of the prescription in the plan concerning Zone 1A habitat is that the Zone 1A criteria relate to living mature or senescing HBT (comprising Mountain Ash, Alpine Ash or Shining Gum) and require more than 12 per 3 hectares in patches greater than 3 hectares. His Honour should have found that, on its proper construction, harvesting of Zone 1A habitat, as defined in table 3.2 of the plan, is prohibited.

4. His Honour erred in holding that the Gun Barrel coupe does not contain Zone 1A LBP habitat. His Honour should have found that the Gun Barrel coupe does contain Zone 1A LBP habitat within the meaning of:

5. His Honour erred in holding that the Freddo coupe or the South Col coupe do not contain Zone 1A LBP habitat.[202] His Honour should have held that the Freddo coupe and the South Col coupe contain Zone 1A LBP habitat within the meaning of:

6. His Honour erred in holding that VicForests is not prohibited, by reason of the precautionary principle, from harvesting the unsurveyed parts of the Toolangi coupes. His Honour should have found that

6. VicForests is prohibited, by reason of the precautionary principle, from harvesting the unsurveyed parts of the Toolangi coupes.

133 At the hearing of the appeal, senior counsel for MyEnvironment, Mr Burnside QC, indicated that Grounds 5 and 6 were not pressed. He also accepted that the plan is a binding document which must govern the field. The LBP AS remained important because it necessarily informed the way the plan was formulated. So too, the precautionary principle informed the approach to be adopted to the construction of the relevant instruments. The focus lay on the construction of the plan and not on the issue of whether the LBP AS imposed legally enforceable obligations independently of the plan or on the effect of the precautionary principle standing alone. This reduced the significance of Grounds 1 and 2. It was accepted that Ground 4 stood or fell with the proper meaning of the plan. Mr Burnside confirmed that the appeal could be decided by reference to Ground 3 alone.

134 Mr Burnside QC also handed up, during the hearing of the appeal, a variation to the proposed form of relief sought:

1. Set aside orders 1 & 2 made by Osborn J on 27 March 2012[203] and in lieu thereof declare that:

1.1 On the proper construction of The Forest Management Plan for the Central Highlands, Zone 1A habitat comprises any patch greater than 3ha, which contains a density of > 4 'hollow-bearing trees' per ha,[204] where 'hollow-bearing tree' means a tree that:

1.1.1 is alive;

1.1.2 contains one or more hollows;

1.1.3 is a Mountain Ash, Alpine Ash or Shining Gum.

1.2 On the proper construction of the Flora and Fauna Guarantee Action Statement: Leadbeater's Possum, Zone 1A comprises any area not less than 3ha of:

1.2.1 mature ash forest (>120 years old) or mixed aged ash forest where the oldest age class is mature (>120 years old); or

1.2.2 regrowth ash forest with at least 12 'live hollow-bearing trees' per 3 ha, where 'hollow-bearing tree' means any tree containing one or more hollows.

1. Order that VicForests pay the costs of the hearing before Osborn J and the costs of the appeal.

(1) Statutory construction in the face of competing purposes

135 The underlying premise of the submissions made by MyEnvironment was that both the LBP AS and the plan should be construed in accordance with the purpose of the legislative scheme, that purpose being to protect the habitat of the LBP. Its written submissions said:

The appeal raises the question whether the legislative scheme can be construed so as to avoid the extinction of the LBP.[205]

As the purpose of the Action Statement is to protect the habitat of [LBP], it is more consistent with the purpose of the legislative scheme to understand the second dot point [in the description of Zone 1A habitat][206] as not confined to older trees.[207]

136 In oral submissions it was put that the stated purpose of the plan was 'to ensure as far as a human can do it, the survival of the [LBP].'

137 In my view, this approach to the construction of the LBP AS and the plan is wrong; it commits the fallacy of assuming that the legislative scheme and the regulatory instruments made under the FFG Act and the Forests Act have a singular purpose. The argument for MyEnvironment is clear and simple. It invited a construction that will best meet the needs of the LBP. The needs of the LBP, for shelter and for nesting, can be met by HBT. With this aim, it is a short step to interpreting any prescription on forestry management as one that should disregard any qualification upon the type of ash forest from which logging should be excluded providing only that the ash forest contains HBT as well as acacia in the understorey. The singular aim is the saving of the LBP; that is best achieved by sequestering any patch of forest with HBT.

138 The understanding of the legislative scheme as having a singular purpose is misconceived. As VicForests submitted, such an understanding fails to recognise that the legislative scheme has a multiplicity of purposes, not only the conservation of the LBP but also the sustainability of the timber industry. Thus, for example, the Code, promulgated under the CFL Act, establishes seven Code Principles to achieve a balance between environmental protection and timber production[208] that include, not only that '[b]iological diversity and the ecological characteristics of native flora and fauna within forests are maintained'[209] but also that:

The ecologically sustainable long-term timber production capacity of forests managed for timber production is maintained or enhanced.[210]

139 Compliance with the Code Principles, informed by knowledge developed from research and experience is directed to:

[E]nsur[ing] that timber can continue to be utilised while ensuring that impacts on water catchments and streams, biodiversity, forested landscapes ... are avoided or minimised.[211]

140 There was recognition that the Code was aimed at managing the 'multiple roles of our forests and plantations in maintaining our natural heritage, biodiversity, health, wellbeing and prosperity'.[212] The Code emphasises the utilisation of scientific knowledge to ensure that timber harvesting is conducted so as 'to manage the impact on soil, water and other values, including biodiversity and cultural heritage'.[213]

141 MyEnvironment placed emphasis upon the 'major' objective of the LBP AS as 'guarantee [ing] the LBP can survive'.[214] However, despite the emphatic nature of that objective, the LBP AS identified, as VicForests submitted, another 'major' objective being the development of measures that result in the preservation of habitat 'and still allow for the extraction and production of wood products on an economic basis'.[215] Furthermore, these objectives were directed at conservation, which was one aspect of the balance sought between 'timber production and environmental protection'.[216]

142 So too, as mentioned above,[217] s 5 of the SFP Act, in its statement of the principles of ecologically sustainable development designed to guide sustainable forestry management, makes plain that decision making processes should effectively integrate both long-term and short-term economic, environmental, social and equity considerations, as recognised by his Honour.[218]

143 Further, the plan has as one of its objectives, that 'a sustainable resource base for forest-dependent industries is maintained', as recognised above.[219] The major challenges identified in the plan were identified as meeting 'a number of conservation and resource use requirements'.[220] In the Foreword, the Secretary stated:

This plan provides for the balanced use and care of State forest, and a framework in which the area's timber industry can continue to confidently invest while providing protection for the natural and cultural value of the forest.[221]

144 The need to balance the twin objectives of conservation of biodiversity and sustainability of the forest industry was also apparent in the summary of 'Major Directions' in the plan. Those Major Directions extended to both the 'Conservation of biodiversity', including the objective that a 'comprehensive system of retained habitat for LBP is established'[222] as well as, under the category of 'Forest Production' the statement, in respect of contractual obligations at the time, that 'Sawlog and residual log supplies will be maintained to meet existing licence commitments'.[223] Moreover, the Major Directions also included the statement, in respect of future timber production capacity, that 'Amendments to the plan will be assessed to ensure that the timber production capacity of State forest is maintained'.[224] Emphatic language was thus used in respect of both the objectives of environmental protection and the sustainability of the timber industry.

145 Furthermore, while Chapter 3 of the plan dealt with Biodiversity Conservation, Chapter 6 dealt with Forest Production, the aims of which included:

• To provide a long-term non-declining supply of hardwood sawlogs to the timber industry.

• To meet sawlog and residual log licence commitments.

• To expand the area of eucalypt forest available for harvesting through reforestation and increase productivity where appropriate.[225]

146 The plan made clear that the maintenance of the viability of the timber industry in the Central Highlands was of critical importance:

The forests of the Central Highlands contain timber and other resources of high economic value. Logs taken from State forest are processed into value-added products such as mouldings, furniture, flooring, kitchen benches and laminated beams. An increasing number of these products are sold on export markets. Logs are also sawn into green structural timbers for the Victorian market. The majority of residual logs, which are a by-product of sawlog harvesting, are used by Australian paper to produce high quality printing and writing papers.

The forest industries which use hardwood logs from State forest are an important part of Victoria's economy. In recent years the industry has invested heavily in drying kilns, planing, moulding and other high technology equipment. The industry has the potential to contribute to further economic growth and the expansion of employment opportunities. In the Central Highlands, the industry directly employs about 1730 people and provides indirect employment for many more.

The timber industry is well established and depends on a secure and sustainable supply of logs to continue investing in equipment and developing export markets. An emphasis of this plan is to provide the industry with a greater security of supply. This plan achieves this greater level of security by providing increased security for forest biodiversity and cultural values across the Central Highlands.[226]

147 This is not to say that, under the plan, the sustainability of the timber industry takes priority over the unmistakable objective of 'ensur[ing] that all indigenous plant and animal species and communities survive and flourish throughout the Central Highlands'.[227] It is not a case of one objective having unequivocal priority over another. It is rather a matter of acknowledging that the legislative scheme has a multiplicity of purposes which the regulatory instruments made under it seek to balance. It is not consistent with that complexity to adopt a construction of the qualifying conditions for a special protection zone that is premised on the achievement of a single purpose.

148 When construing legislation that has a multiplicity of purposes, or seeks to strike a balance between competing interests, it is necessary to keep in mind the observation of Gleeson CJ in Carr v Western Australia[228] that the purposive rule of statutory interpretation, embodied in Victoria in s 35(a) of the Interpretation of Legislation Act 1984, is of limited assistance in construing legislation, or regulatory instruments, that embrace numerous potentially conflicting objectives in relation to which the court has to determine from the language used where the intended balance lies.[229] In that context, he expressly eschewed the adoption of a construction that furthered the pursuit of one of the competing objectives to the greatest extent possible while leaving the other objectives unfulfilled. He said:

In the interpretation of a provision of an Act, a construction that would promote the purpose or object underlying the Act is to be preferred to a construction that would not promote that purpose or object. ... That general rule of interpretation, however, may be of little assistance where a statutory provision strikes a balance between competing interests, and the problem of interpretation is that there is uncertainty as to how far the provision goes in seeking to achieve the underlying purpose or object of the Act. Legislation rarely pursues a single purpose at all costs. Where the problem is one of doubt about the extent to which the legislation pursues a purpose, stating the purpose is unlikely to solve the problem. For a court to construe the legislation as though it pursued the purpose to the fullest possible extent may be contrary to the manifest intention of the legislation and a purported exercise of judicial power for a legislative purpose.[230]

To take an example removed from the present case, it may be said that the underlying purpose of an Income Tax Assessment Act is to raise revenue for government. No one would seriously suggest that s 15AA of the Acts Interpretation Act has the result that all federal income tax legislation is to be construed so as to advance that purpose. Interpretation of income tax legislation commonly raises questions as to how far the legislation goes in pursuit of the purpose of raising revenue. In some cases, there may be found in the text, or in relevant extrinsic materials, an indication of a more specific purpose which helps to answer the question. In other cases, there may be no available indication of a more specific purpose. Ultimately, it is the text, construed according to such principles of interpretation as provide rational assistance in the circumstances of the particular case, that is controlling.[231]

150 In referring to two earlier decisions, Kelly v The Queen[232] and Nicholls v The Queen,[233] which had raised similar issues of statutory construction in the context of a legislative scheme set against a background of competing interests, Gleeson CJ explained that it is not a question of simply identifying the purpose of the legislation but rather asking how far the legislation goes in fulfilling that purpose:

As explained in Kelly and Nicholls, the general purpose of legislation of the kind here in issue is reasonably clear; but it reflects a political compromise. The competing interests and forces at work in achieving that compromise are well known. The question then is not: what was the purpose or object underlying the legislation? The question is: how far does the legislation go in pursuit of that purpose or object?[234]

151 In Carr the High Court was concerned with the interpretation of s 570D of the Criminal Code (WA) which governed the admissibility of admissions made during police interviews by persons accused of certain serious criminal offences. Section 570D(2) created a mandatory rule of exclusion. Admissions made during an interview were not admissible at trial unless the evidence was videotaped, or there was a reasonable excuse for the absence of a videotape recording, or there were exceptional circumstances.[235] Section 570D(4) provided that a 'reasonable excuse' included that the accused did not consent to the interview being taped.[236] An accused gave a formal interview that was videotaped but contained no admissions. He also had an informal conversation in the lockup in which he made admissions. This conversation was also recorded on videotape but without his knowledge. He argued that the informal conversation should not be admitted into evidence on the basis that there should be implied into s 570D an obligation that a suspect must consent to videotaping. The Court held that there was no basis for implying into s 570D such a requirement. In arriving at that construction, Gleeson CJ adverted to the choice made by the legislature in adopting a limited step in advancing the objective of protecting the integrity of the administration of the system of criminal justice. He said:

Section 570D established a qualified, but otherwise specific, rule of exclusion of evidence of admissions. That, on any view of the matter, was only a limited step in pursuit of the object of protecting citizens against unfair police conduct, and protecting the integrity of the administration of criminal justice. To read s 570D as containing another ground of exclusion of evidence would only be to take a further limited step in pursuit of the same object. The legislation plainly did not attempt to deal with all possible problems of police misconduct or accusation of such misconduct. It cannot be said that the underlying purpose of the statutory provision would be defeated unless there were two limited rules of exclusion rather than one. The ground of exclusion under s 570D(2) was complete in itself. No additional ground of exclusion was implied.[237]

152 Nicholls had also been concerned with s 570D of the Criminal Code (WA) where Gleeson CJ identified the difficulties inherent in statutory construction of an Act where the Legislature had adopted a compromise:

Legislation such as s 570D seeks to strike a balance between competing considerations and interests. A search for legislative purpose needs to take account of the fact that legislatures rarely engage in the pursuit of a single purpose at all costs. Problems of statutory construction often arise because the extent to which the legislature intends to pursue a given purpose is unclear. When, as is so obviously the case with s 570D, Parliament adopts a compromise, a court may be left with the text as the only safe guide to purpose.[238]

153 Kelly also concerned the admissibility of admissions made during questioning by the police and the video-recording of that questioning. The Court held that when an accused after a recorded interview, during which he had retracted an earlier unrecorded confession, said 'Sorry about the interview - no hard feelings, I was just playing the game', that statement was admissible as it was not 'made in the course of official questioning' within the meaning of s 8(1)(b) of the Criminal Law (Detention and Interrogation) Act 1995 (Tas). Had the statement occurred in the course of official questioning, it would have been excluded unless videotaped, subject to specified exceptions. The Court acknowledged the problem that the Tasmanian legislation, and the legislation of other States, was seeking to resolve, including the problem of the fabrication of confessions, misunderstanding, mis-recollection, coercion or oppression in a broad sense. It described the variety of possible solutions that had been taken up by one or other Australian jurisdiction, including the exclusion of confessions, unless videotaped, by persons who were or ought to have been suspected,[239] and the exclusion of confessions, unless videotaped, of confessions made during questioning of persons in custody.[240]

154 In a joint judgment, Gleeson CJ, Hayne and Heydon JJ said:

The appellant submitted that s 8(1)(b) must be construed so as to promote the purpose or object of the Act. That submission may be accepted. But it raises two questions. First, what is the purpose or object of the Act? Secondly, what is the construction which promotes that purpose or object?

...

[T]hough it may be accepted that the purpose or object of s 8 of the Act was to overcome the 'perceived problems' identified in many earlier cases, as the range of legislative responses shows, those problems can be overcome in different ways and to different degrees. The 'purpose or object' identified does not compel any particular construction of the quite detailed language of s 8 of the Act. What the correct construction is must depend on the particular words used.[241]

155 In my view, the complexity here of the statutory scheme and the competing aims apparent in the regulatory context mean that the construction of the LBP AS and the plan is an occasion on which a compromise has been adopted. It is a circumstance in which '[t]he "purpose or object" identified does not compel any particular construction'.[242] As discussed above, it is not tenable, in my view, to conclude, even on the face of the instruments, that the LBP AS and the plan are seeking to pursue a single purpose or objective. The fact that the LBP AS and the plan are directed at the fulfilment of multiple purposes means that the 'correct construction ... must depend on the words used',[243] within the relevant context.

156 I turn then to the critical task, that of arriving at the correct construction of the words used. This is a difficult exercise, as was accepted by both parties to the appeal, because the regulatory instruments do not reveal the standard of drafting, or care, that is present when legislation is prepared by parliamentary counsel. Nevertheless it is the words chosen, in their context, which demand interpretation.

(2) The separate category construction in the LBP AS

157 The primary submission made by MyEnvironment is that the LBP AS, and the plan, should be construed with the understanding that what is critical to the survival of the LBP are hollows in trees; it is the hollows that provide shelter and essential breeding spaces. LBP are dependent on HBT, not on HBT of a certain age. MyEnvironment submitted that there was no evidence to suggest that LBP selectively prefers trees older than 120 years;[244] rather, they require for their preservation HBT of any age.

158 MyEnvironment's emphasis upon the essential character of the presence of hollows was supported by the evidence given by Professor Lindenmayer about the relevance of the age of the tree when determining whether it is a HBT. Asked to comment on an opinion expressed by Mr Ryan that trees at the stage of regeneration, regrowth, mature younger or mature older 'are not considered suitable' for LBP habitat, Professor Lindenmayer disagreed with that assessment and said:

The definition of suitable habitat, the knowledge of the suitable habitat, Your Honour, is related to the abundance of hollow-bearing trees, full stop. It relates to whether a tree has a hollow.[245]

159 Earlier in his testimony Professor Lindenmayer had given evidence that:

[A]ll of the work that we have done on hollow-bearing trees and on the habitat requirements of Leadbeater's possum, Your Honour, have been based on the presence of any tree with a hollow on a site and that has been the way we have conducted our research since 1983 and continuously through to 2012.

160 Later, referring to a study which he published in 1993 in which he measured 2,315 HBT across the Central Highlands, he observed that:

The mean size of a hollow-bearing tree is 1.9 metres but there are hollow-bearing trees as small as 0.5 of a metre and in all of our work on the habitat requirements of the Leadbeater's possum we have looked at the total number of hollow-bearing trees on a three hectare site to develop the statistical relationships for the presence and/or abundance of a species on a site.

161 During examination in chief, Professor Lindenmayer acknowledged that there was a difference between an area identified as Zone 1A habitat and an area that might nevertheless be suitable as habitat:

Q: Is there a difference between an area being identified as Zone 1A habitat and an area being an area that a Leadbeater's possum might in fact inhabit?

A: Yes, there is. The Leadbeater's zoning system is based on trying to protect what might be - what is Leadbeater's possum habitat but the habitat requirements of Leadbeater's possum, that understanding is based on the statistical relationships between the abundance of hollow trees on a site and the presence, absence and abundance of Leadbeater's possum on a site. So you are correct, they are not necessarily the same thing.

162 In cross-examination, he was asked whether diameter was generally a good indication of whether a tree was pre-1900 or not and he accepted that the larger the diameter the more likely it was that the tree had hollows. Of diameter, he said:

A: It can be used as a reasonable surrogate but there are times when it's appropriate and accurate and other times when it's not. I repeat, that's why we measure every tree which has a hollow and we don't make an assumption about those relationships.

Q: The larger the diameter, the broader the tree, the greater the chance of hollows forming within the cavities, is that the case?

A: The larger the tree, the larger the diameter, the greater the probability that the tree will have a cavity or a hollow.

163 He was asked about his earlier evidence that, saplings and seedlings aside, there is no size limitation on HBT and gave the following answer:

A: Your Honour, the key issue here is whether a tree has a cavity or not and whether or not there's a careful assessment to determine whether there's a cavity in a tree or not.

Q: Do you accept that the very best habitat, premium habitat for the Leadbeater's possum consists of large older trees containing hollows?

A: Your Honour, the concept of best and premium comes with value judgments. The way that we have completed our analysis over many years is to look at the probability of occurrence and the abundance of the species in relation to those attributes of the forest, the number of hollow-bearing trees, the amount of wattle in the understorey. It's a probabilistic relationship for presence or absence or it's what we call a Poisson relationship for the abundance of the species.

164 Professor Lindenmayer was asked about the use of the term 'large' in relation to HBT in the papers he had published. He conceded that typically trees take 120 years to first begin to develop hollows, and would typically be 150 to 190 years before they can be suitable nesting habitat. But, he insisted, this is a probabilistic relationship:

[T]here are times when you will have smaller trees than that, younger trees than that which will have cavities in those trees and those cavities may be occupied and used by Leadbeater's possum and there may be trees older than 190 years that may not have cavities and that's the underlying reason why it is critically important to do a careful assessment of the trees in a particular area to confirm the presence of hollows, to then do an assessment of the abundance of hollow-bearing trees in an area and that has always been the methodology that we have applied in all cases since 1983 and we have to, Your Honour, apply the same methodology on a repeated basis to make sure that our work is sound.

165 Given the critical importance of hollows to the nesting requirements of the LBP, the submission of MyEnvironment was made by carefully distinguishing the first and second dot points of the LBP AS. It conceded that 'mature ash forest' is, on all the evidence, likely to contain a significant number of HBT. Thus, if one can identify a forest satisfying that description, as it appears in the first dot point of Zone 1A in the LBP AS, there is no need to count HBT. The first dot point thus uses the age of a tree as a proxy for hollows, justifiably in this context.

166 By contrast, the second dot point, it was submitted, looks at the thing the LBP is actually interested in, the presence of hollows, and concentrates on the existence of a certain number of HBT. It does not proceed by means of the use of age as a proxy.

167 MyEnvironment argued that the error committed by his Honour was to fail to pay sufficient attention to the fact that the first dot point used age as a proxy for hollows while the second dot point eschewed the use of a proxy and was concerned directly with the fact of the existence of hollows and not with age. It was submitted that the judge's reasoning on the issue[246] was 'overly concerned with grammar and not sufficiently concerned with the ultimate objective of saving the [LBP] habitat'.[247] A proper approach, it was argued, would recognise that the first dot point assumed that all forest older than 120 years will contain a sufficient number of HBTs to provide a viable habitat; the second dot point acknowledges that regrowth forests can be old (albeit not 120 years old) and that some will contain a sufficient number of HBTs.

168 By failing to be conscious of the difference in the subject-matter of the first and second dot points, it was argued, the judge had erred by running the first and second dot points together as if they were to be read as a single definition. Moreover, it was submitted, such running together impermissibly used age as a proxy for hollows in the second dot point where such a proxy is impermissible.

169 It was conceded that there is a correlation between the age of a montane ash tree and the likelihood of that tree containing hollows. It was also conceded that there was a correlation between the height of a tree, the diameter of the tree and the number of hollows it bears[248] and, to the extent that there is a correlation between height, diameter and age,[249] there is a correlation between age and the number of hollows. However, it was submitted, that is nothing more than a correlation and it would be wrong to substitute the age of a tree for the characteristic with which it correlates, the presence of hollows, when it is the existence of hollows that is critical to the survival of the LBP and not the maturity of the tree.

170 MyEnvironment submitted that because hollows can occur in trees that are less than 120 years old and even less than 90 years old, and because the maximum population densities of LBP occur in regrowth forests 15 to 50 years with more than six PNT per three hectares,[250] the age of a tree, while it may be a useful indicator of whether a tree is likely to contain hollows, 'as a matter of choice for the LBP', it is 'probably irrelevant'. In identifying the habitat of the LBP, the age of a tree should not be treated as the proxy for what the LBP is interested in, namely, the existence of hollows. In the context of a mature ash forest the use of age as a proxy may be facilitative because the maturity of the forest is tantamount to a guarantee of the presence of HBT, but outside of that context it is wrong to treat the age of a tree as a proxy for the existence of hollows; and the second dot point of the LBP AS does not purport to do so, and should not be read as doing so.

171 However, these submissions of MyEnvironment face a number of related difficulties:

(1) A 'proxy' is something that represents or stands in substitution for something else. A proxy acts as a surrogate. MyEnvironment may be correct in submitting that the reference to 'mature ash forest' in the first dot point functions as a proxy because there is no need for a further investigation of the presence of HBT. It can properly stand in substitution for HBT, as the judge recognised. However, there is nothing in the judge's reasoning to support the view that, with respect to the second dot point, he construed the age of a tree in a regrowth ash forest as a surrogate for the presence of hollows; nowhere in his reasons does he conclude that the age of a tree alone, in a regrowth ash forest, can represent or stand in substitution for the presence of hollows.

(2) Far from adopting the age of a tree as a proxy for the existence of hollows, the judge construed the second dot point as requiring that there be a certain density of HBT. Insofar as his construction qualified the eligible HBT to those that are mature or senescing, that qualification did not derive from a misplaced extension of the proxy in the first dot point, but resulted rather from an appreciation of the preponderance of scientific evidence that the type of nest tree preferred by the LBP generally take several hundred years to develop[251] and an understanding that the definition of Zone 1A was to be read against that background.

(3) The proposition espoused by MyEnvironment that although the age of a tree may be a useful indicator, it is 'probably irrelevant', 'as a matter of choice for the LBP', is inconsistent with the statistically significant correlation between the age of a tree and its use by LBP as a habitat. The evidence established that not only is there a correlation between the age of a tree and its diameter, and its diameter and the existence of hollows, but there was also evidence that there was a statistical relationship between larger older trees and an abundance of hollows.[252] In particular, large old trees in regrowth ash forest tend to have a large number of hollows. This is so because, as mentioned above,[253] they will have developed to an age where hollows are typically developed and, in addition, in a regrowth forest, are likely to have undergone the disturbances of fire and logging which give rise to stem damage and the formation of cavities.[254] Against that background, to treat the age of a tree as 'probably irrelevant' is to adopt the perspective of an individual LBP who is seeking to make a nest and evaluating whether any particular individual tree has cavities in which to breed without concern as to the age of the tree. As the judge recognised, this is not the perspective from which the LBP AS has been prepared. Far from looking at each individual tree from the perspective of an individual LBP, the LBP AS is prepared as a managerial measure to permit scientifically informed decisions to be made about the protection of the environment and biodiversity and the sustainability of the timber industry. In this context, the existence of a correlation between age and an abundance of hollows is significant. It is significant because it permits macro-level managerial decisions to be made about what patches of forest should be included within a SPZ. As all the scientific evidence relied on by the judge demonstrated, the age of a tree is highly relevant to the likelihood of its containing hollows. It is precisely those probabilistic relationships that ground regulatory instruments such as the LBP AS.

(4) The management prescription represented by Zone 1A habitat is not designed to capture all suitable habitat of the LBP but only to capture optimal habitat, or habit with presently existing potential. If the capture of all suitable habitat was the only objective of the LBP AS then indeed all HBT, regardless of age, could be preserved for the LBP. More precisely, all patches of forest containing an appropriate density of HBT would warrant the status of a SPZ from which forestry would be excluded. However, as discussed above, the statutory scheme and the regulatory instruments manifest an intention to achieve a balance between conservation of the LBP and the sustainability of the timber industry and, in doing so, identify that that balance is achieved by affording the most stringent form of protection to the optimum habitat of the LBP, and the presently existing potentially optimum habitat of the LBP, not to any suitable habitat that might be available.

(5) Moreover, there was evidence from a draft internal departmental guide for survey standards that, while 'determining if a tree contains hollows can be difficult', identification is much easier in mature or senescent trees:

Very large, live trees (ie mature or senescent: Smith and Lindenmayer 1988) with irregular crowns, broken limbs, buttressing and viewable hollows are easily identified as [HBT].[255]

Ready identification is clearly relevant to regulation and management.[256]

172 MyEnvironment further submitted that the judge's treatment of the definition of Zone 1A in the LBP AS made the second dot point redundant. If the first dot point is to be read as trees more than 120 years old and that is a sufficient condition for eligibility then it adds nothing to that to construe the second dot point as consisting in trees more than 120 years old with hollows because those trees will already be protected within Zone 1A. The second dot point, read as having some work to do, should be construed as recognising that trees younger than 120 years can be included with Zone 1A providing they have hollows. MyEnvironment sought to demonstrate that the second dot point has real work to do independently of the first dot point and his Honour's construction failed to reflect this. This would be so, it was argued, where, for example, regrowth ash forest contained only a small handful of surviving trees of older age in which case it could not be sensibly characterised as a mixed age forest. However if, upon investigation, it was found to satisfy the density requirement of live HBT, then such regrowth forest ought be included within Zone 1A habitat independently of the eligibility conditions expressed in the first dot point. Yet, so it was submitted, his Honour's construction wrongly would not permit such regrowth forest to be included.

173 There is an anomaly, however, in the position adopted by MyEnvironment, as his Honour recognised.[257] The first dot point refers to two types of forest, mature ash forest, on the one hand, and mixed aged ash forest where the oldest age class is mature, on the other hand. It was accepted that all mature ash forest, forest older than 120 years old, will contain enough HBT to create a viable habitat, and this assumption is a good one given the overwhelming evidence that it is mature ash trees which exhibit the preponderance of hollows. Thus, according to MyEnvironment's argument, the first category of the first dot point treats, permissibly, the age of a tree in a forest of trees all over 120 years old as a proxy for hollows. However, the second category of the first dot point could not permissibly treat the age of a tree as a proxy for hollows. This is because the second category, being of 'mixed age' ash trees will include not only a class of mature trees (the oldest age class in the category) but will also include immature trees. One can ask rhetorically: why should 'mixed age ash forest where the oldest age class is mature' qualify as Zone 1A habitat regardless of whether or not it includes HBT, let alone the stipulated density of HBT? Given that it is the presence of hollows which is significant for LBP, and essential to their survival, it would be paradoxical if a category of forest identified as warranting the most stringent protection was forest which might not include HBT at the stipulated level of density. Yet the separate category construction contended for by MyEnvironment has precisely this consequence. This is a significant anomaly and his Honour was correct to regard it as such.

174 VicForests submitted that there is an additional incongruous consequence that flows from MyEnvironment's construction. As mentioned, if the second dot point does not qualify the second category in the first dot point, 'mixed age ash forest where the oldest class is mature' would classify, without more, as Zone 1A habitat. If that was so, it asked, why would there be a need to stipulate separately that mature ash forest is Zone 1A habitat? If it was a sufficient condition for eligibility as Zone 1A habitat that a mixed age ash forest included, as its oldest class, mature trees, there would be no need, it was argued, to specify mature ash forest because that class would be picked up always, or almost always, within the mixed aged ash forest as its oldest class. The first category in the first dot point would be a sub-set of the second category of the first dot point and there would be no need for it to receive separate mention. However, it might be responded, in support of MyEnvironment, that the first category may be confined to a class of uniform longevity, or at least trees that are uniformly older than a particular age, rather than a class of trees within a forest of trees of mixed age.

175 The difficulties that flow from the construction proffered by MyEnvironment demonstrate that it does not satisfactorily explain all of the indicia of Zone 1A habitat. It is not sufficient for one of the dot points to give effect to what MyEnvironment would like the habitat prescription to be; if MyEnvironment's construction of the second dot point is to be tenable it must reveal a satisfactory interpretation of how each of the dot points can be construed as separate categories. That is, an explanation of how the second dot point can function independently must also explain how the remaining categories can function independently. This it fails to do. Most especially, it leaves the second category in the first dot point as functioning, counter-intuitively, without any particular HBT density requirement.

176 The more coherent path is to adopt the approach taken by his Honour and view the category of 'mixed aged ash forest where the oldest age class is mature' within the LBP AS as 'necessarily mean[ing] forest which comprises regrowth mixed with mature trees, because trees younger than mature are regrowth'.[258] This is supported by the observation that it is regrowth forest in which the greatest density of mature or senescing HBT occur because the mature trees left standing by the disturbance that created the regrowth are not only old, and thus likely to develop hollows, but also have experienced the disturbance which facilitates the formation of hollows.[259] The density requirement of HBT identified in the second dot point thus applies to this category.

177 In any event, even if the second dot point did identify a separate category, one that might overlap only to some degree with the category of mixed aged ash forest where the oldest age class is mature, the context is one in which the LBP AS recognises that regrowth forests 'require >150 years of growth before fire can effectively create the necessary floristics and structural diversity critical for [LBP] habitat'.[260]

178 In my view, for all the reasons espoused by his Honour, the LBP AS makes clear that it intends that the most stringent form of protection will be reserved for those patches of montane ash forest where the HBT present are mature or senescing.

179 I reject MyEnvironment's construction of the LBP AS.

180 MyEnvironment submitted that the habitat protected by the plan is informed by Table 3.2 where the definition of Zone 1A is apt to embrace both of the dot points in the definition of Zone 1A in the LBP AS. Table 3.2 focuses not on the proxy, but on what is important, namely, the number of HBT. Although MyEnvironment accepted that it is much more likely that older trees will have hollows than younger trees, it submitted that the definition of Zone 1A habitat in Table 3.2 does not require that all 12 HBT will be older than any particular age.

181 It was submitted that his Honour, in holding that Zone 1A applies only in relation to 'mature or senescing trees', in effect disregarded Table 3.2 as otiose whereas he should have held that it applies to any tree that is alive and contains hollows, as defined in Table 3.2. He should not have allowed the parenthetic insertion in the description of Zone 1A in the Management Prescription to redefine the zone which could be read intelligibly and plainly without that insertion. To rely on the parenthetic insertion to alter the explicit definition would be, wrongly, 'a case of the tail wagging the dog'. Moreover, it was argued, he should not have relied on the description preceding Table 3.2 because it was not a faithful representation of what was provided for in the LBP AS, which informed the plan, because, for example, its reference to 'living older trees' under Zone 1A omitted all reference to the second dot point and the density requirement for HBT.

182 MyEnvironment argued that the 'natural construction' of Table 3.2 was that there is no age requirement with respect to HBT. This was consistent with the construction of the LBP AS which it favoured. It submitted that by contrast with the vague quality of the words 'mature' and 'senescing', Table 3.2 is precise and the plan is imprecise until Table 3.2 is considered.

183 In its argument, MyEnvironment sought to rely on the categories and words of Table 3.2 to crystallise the obligations submitted to be imprecisely set out in the Management Prescription. A fair reading of the Management Prescription and Table 3.2 reveals that the opposite is the case. A comparison between, on the one hand, the description preceding Table 3.2 and the Management Prescription, and, on the other hand, Table 3.2, indicates that Table 3.2 summarises some but not all of the information contained in the former. It seeks to present in a semi-quantitative or semi-mathematical way a summary of the salient features of the Management Prescription. As with most summary tables or charts, it does not purport to reproduce all of the information in the sources summarised. It provides 'information at a glance' by way of the semi-mathematical or condensed expression of the principal features of the Management Prescription. Such condensed expression entails the omission of qualifications. It would be a mistake, however, to read Table 3.2 as though the qualifications it omits did not remain relevant to an understanding of the Management Prescription imposed by the plan. This is not a matter of permitting a parenthetical statement to alter an explicit definition; it is rather to recognise that Table 3.2 omits significant qualifications without which the nature and meaning of the zoning arrangement is changed considerably. On this approach, as VicForests submitted, Table 3.2 and the Management Prescription can, and should be, read consistently with each other. The flaw in the approach adopted by MyEnvironment is to ignore significant provisions in the plan, and not to read the plan as a whole or give full effect to all its provisions.

184 The anomalies that result from a reading of Table 3.2 without reference to the balance of the plan suggest that it should be read as nothing more than a schematic and condensed representation of the zoning system and should not be read in isolation or so as to disregard, or take priority over, the Management Prescription or the other descriptions of Zone 1A or Zone 1B. Most importantly, the anomalies suggest that the omission of qualifications in the description of Zone 1A and Zone 1B in Table 3.2 should not be understood as deliberate. Rather, it is necessary to read Table 3.2 in the context of the plan as a whole and as importing the qualifications of 'mature or senescing' in its reference to HBT. Zone 1A should be read consistently with the Management Prescription and the other indicia throughout the plan as requiring the prescribed density of mature or senescing HBT. Zone 1B should be read as requiring the prescribed density of dead mature or senescing trees and wattle understorey.

185 I reject MyEnvironment's challenge to the judge's construction of the plan.

186 MyEnvironment submitted that the judge was wrong to reject the argument that the words 'mature' and 'senescing' are too vague, subjective and imprecise to constrain the definition of Zone 1A set out in Table 3.2. It relied on the evidence of Professor Lindenmayer that the terms 'mature' and 'senescent' are not terms used in his discipline because they lack precision. The key consideration was whether the tree had a hollow.

187 Professor Lindenmayer gave evidence that 'the term "senescing", to my understanding, means a tree that is no longer growing very rapidly, that the crown is starting to break up, the top of the tree may break away and you may have lateral sub crowns in the tree.' He also said that it is a term he does not use 'terribly much' because it 'lacks the precision that we need for the kinds of work that is important in the work we do.' Professor Lindenmayer defined 'mature' to mean 'a younger tree that is starting to grow in size and in characteristics beyond a regrowth tree.' He described this term too as 'quite vague and difficult to work with as a definition.' Rather, he said, he classifies trees by form, from 1 through to 8 without adding the additional characteristic of senescing mature regrowth.[261]

[W]e tend not to use terms such as maturity and senescence in our assessments of trees and there are good reasons for that including the vagaries of definition but also the potential for hollows to develop for reasons by way, for example, of events such as wound injury from a fallen branch .... .

...

[W]e don't use the term mature. We look at the tree, we assess the tree carefully with binoculars, and if that reveals the presence of a hollow, then the tree has its diameter measured, the location is recorded and it's mapped and it's carefully recorded then in a database and we maintain very strict codes of data quality and data curation because we need to analyse and re-analyse data sets and to continue to maintain the quality of these data sets as a key part of Australia's environmental infrastructure.

189 Mr Spencer, Director, VicForests, also acknowledged that the term 'mature' is not precise. In cross-examination he accepted that he would not say that a tree could not be mature at 100 years old, or 99 years old, or 98 years old, or 90 years old. However, he considered that the source of its imprecision related to the fact that it sought to describe a natural characteristic.

190 Mr Spencer also accepted, during cross-examination, that 'senescing' was 'to a degree subjective' and 'requires a lot of interpretation'. He accepted that 'there can be trees where there's a difference in opinion as to the level of senescence'.

191 Mr Michael Ryan, a forest scientist with VicForests, also gave evidence of his understanding of the terms 'mature' and 'senescing'. He said that a mature tree would be 'generally define[d] ... as something greater than 120 years of age', while a senescing tree 'is a tree that's gone past its maturity and is starting to decay substantially'. Later, he explained:

[W]hen a tree's mature the senescing part is when it's really starting to fall apart effectively and we are talking about trees in the far later stages of its life ... .

192 In evaluating the meaning of the words 'mature' and 'senescing' in the LBP AS and the plan it must be remembered that the words are seeking to describe visually discernible qualities of montane ash trees. It is to be expected that the boundaries of such qualities may inherently lack some precision. The terms are not susceptible to mathematical definition or exactitude. However, in my view, it is clear from the regularity with which the terms are used throughout the regulatory instruments that they adequately convey a meaning within that context. Moreover, the description of the various stages of senescing has been reduced to visual form by Jacobs, as was set out above,[262] and the stages of senescense have also been depicted by Professor Lindenmayer in the 1988 report[263] and the 1991 paper.[264] There was evidence that these visual forms have had practical utility in assisting identification of the relevant HBT[265] and were well-understood by foresters.

193 I consider that the judge was correct to conclude that the terms 'mature' and 'senescing' are not so uncertain as to be meaningless.[266]

194 The challenge to the judge's reasoning, based on the imprecision of the words 'mature' and 'senescing', fails.

195 VicForests submitted that the judge had erred in failing to read the eligibility condition for Zone 1A habitat as requiring that HBT be both mature and senescing. It was argued that the requirement for both characteristics would provide a visual guide for foresters for determining eligibility because it would involve recognising that the crown of a tree had been broken together with the other visual identifying features of senescence. Determining maturity alone in the absence of senescence is more difficult. Moreover, VicForests relied on the difference in language between Zone 1A and Zone 1B in the Management Prescription of the plan, the former referring to 'living mature and senescing trees' the latter referring to 'dead mature or senescent trees'.[267]

196 The primary position of MyEnvironment was that Table 3.2 should be read in isolation, not informed or qualified by other provisions of the plan, and Zone 1A does not depend upon the HBT present in a patch of forest being either mature or senescing. However, in response to the Notice of Contention MyEnvironment submitted that 'mature' and 'senescing' should be understood as identifying two separate categories only one of which need be satisfied by a HBT to be included within Zone 1A habitat at the required density. For a tree to be senescing it must necessarily already be mature. Thus, to impose as an eligibility condition for inclusion in Zone 1A habitat that a tree be both senescing and mature would be tautologous in that the requirement for maturity in a senescing tree would always be satisfied - the requirement of maturity would be redundant. The plan could have insisted that a tree only exhibit senescence and it would have achieved the same outcome. The inference should be drawn, it was submitted, that the plan would not have imposed a requirement that was redundant. Rather, the eligibility condition should be read disjunctively, as the judge read it, to refer to HBT that are either mature or senescing.

197 I agree with MyEnvironment that only a disjunctive reading renders intelligible the requirement of maturity.[268] So read, the eligibility condition refers to two classes of HBT: those that are mature but not, or not necessarily, senescing and those HBT that are senescing (and are necessarily mature). To conclude otherwise would be in effect to confine Zone 1A habitat to senescing HBT and that is not supported by the numerous references to the maturity of an HBT throughout the regulatory instruments. The eligibility condition should be read as referring to either mature or senescing HBT.

198 I reject the submissions of VicForests in support of the Notice of Contention.

199 I reject MyEnvironment's submissions on the construction of the plan and I reject MyEnvironment's construction of the LBP AS.

200 My conclusions on the construction of the plan have as a consequence that the Gun Barrel coupe does not contain Zone 1A habitat. MyEnvironment's challenge to the judge's conclusion on the lawfulness of variable retention logging of Gun Barrel depended upon its construction of the plan being accepted. That challenge has been unsuccessful.

202 I have had the considerable benefit of reading the draft judgments of Warren CJ and Tate JA. I agree with those judgments, and that the appeal should be dismissed.

CFL Act Conservation, Forests and Lands Act 1987.

The Code Code of Practice for Timber Production 2007, issued by the Department of Sustainability and Environment in 2007.

Coupe A single area of native forest or plantation of variable size, shape and orientation from which timber is harvested in one operation.

FFG Act Flora and Fauna Guarantee Act 1988.

HBT AS Department of Sustainability and Environment (Vic), Flora and Fauna Guarantee Action Statement #192: Loss of hollow-bearing trees from Victorian native forests and woodlands.

LBP AS Department of Sustainability and Environment (Vic), Flora and Fauna Guarantee Action Statement #62: Leadbeater's Possum Gymnobelideus leadbeateri.

The plan Forest Management Plan for the Central Highlands (May 1998), published by the Department of Sustainability and Environment.

Senescence The condition or process of deterioration with age.

SFT Act Sustainable Forests (Timber) Act 2004.

[1] These terms are defined in the reasons of Tate JA at [38] and [48] respectively.

[2] MyEnvironment Inc v VicForests [2012] VSC 91, [110]-[111].

[5] [1998] HCA 28; (1998) 194 CLR 355.

[7] See [148] and following.

[8] [2007] HCA 47; (2007) 232 CLR 138, 142-3 ('Carr').

[9] [2013] HCA 36; (2013) 87 ALJR 1009, 1016 [40]-[41]; [2013] HCA 36; 300 ALR 460, 469. See also Kline v Official Secretary to the Governor General [2013] HCA 52, [37].

[11] See Brennan v Comcare [1994] FCA 1147; (1994) 50 FCR 555, 574 (Gummow J); Morrison v Peacock & Roslyndale Shipping Co Pty Ltd [2000] NSWCCA 452; (2000) 50 NSWLR 178, [33] (Spigelman CJ); Victims Compensation Fund v Brown [2002] NSWCA 155; (2002) 54 NSWLR 668, [9] (Spigelman CJ); Applicant A v Minister for Immigration and Ethnic Affairs (1997) 190 CLR 225, 248 (Dawson J); Western Australia v Ward [2002] HCA 28; (2002) 213 CLR 1, [658] (Callinan J); Attorney-General (WA) v Marquet [2003] HCA 67; (2003) 217 CLR 545, [145] (Kirby J); Director General, Dept of Education and Training v MT [2006] NSWCA 270; (2006) 67 NSWLR 237, [50] (Spigelman CJ); NSW Food Authority v Nutricia Australia Pty Ltd [2008] NSWCCA 252; (2008) 72 NSWLR 456, [125] (Spigelman CJ); National Rugby League Investments Pty Limited v Singtel Optus Pty Ltd [2012] FCAFC 59; Australian Postal Corporation v Sinnaiah [2013] FCAFC 98.

[12] Rodriguez v United States [1987] USSC 36; 480 US 522 (1987), 525-526.

[14] See Freeman v Quicken Loans, Inc. 132 S.Ct. 2034 (2012), 2044; American Express Co. v Italian Colors Restaurant 133 S.Ct. 2304 (2013), 2309; Equal Employment Opportunity Commission v The Chicago Club [1996] USCA7 611; 86 F.3d 1423 (17th Cir. 1996), 1434.

[15] (1988) 13 NSWLR 315.

[17] [2002] NSWCA 155.

[19] [2003] HCA 54; (2003) 77 ALJR 1797, 1804 (citations omitted).

[20] R S Geddes, 'Purpose and Context in Statutory Interpretation' in Statutory Interpretation, Principles and pragmatism for a new age, Judicial Commission of NSW Education Monograph 4 - June 2007, 127, 153.

[21] See [140] and following.

[22] Timber extraction in areas within these zones is either prohibited or subject to restrictions.

[23] Appellant's Submissions in Reply [10].

[24] See MyEnvironment Inc v VicForests [2012] VSC 91 ('Reasons').

[25] Summary of the Proceedings and Issues, [14].

[27] Schedule 2. A 'taxon' is defined as 'a taxonomic group of any rank into which organisms are categorised': FFG Act, s 3.

[28] It was also found in a small colony in the Yellingbo Nature Reserve.

[29] Reasons, [2]-[3], quoting from trial exhibit C, report of Professor David Lindenmayer dated 16 January 2012 with modifications and letters of instruction ('Lindenmayer report').

[31] Summary of the Proceedings and Issues, [24].

[33] Trial Exhibit X, Andrew P Smith and David Lindenmayer, 'Tree Hollow Requirements of Leadbeater's Possum and other Possums and Gliders in Timber Production Ash Forests of the Victorian Central Highlands' (1988) 15 Australian Wildlife Research 347.

[34] Summary of the Proceedings and Issues, [25].

[37] Summary of the Proceedings and Issues, [26].

[38] The TRP applicable to the Toolangi coupes is the Timber Release Plan 2011-2016, which was approved on 15 June 2011, notice of approval for which was published in the Victorian Government Gazette (L Miezis, Acting Executive Director Forests and Parks (Vic), 'Notification of Approval of Timber Release Plan', Victorian Government Gazette, No G 25, 23 June 2011, 1335, 1352).

[39] Victoria, Gazette: Special (State Owned Enterprises (State Body - VicForests) Order 2003), No S 198, 28 October 2003, 3(2).

[41] Reasons, [123]. See the discussion below.

[43] The relevant Department is now named the Department of Environment and Primary Industries as of 9 April 2013 (Victoria, Gazette: Special (Order Changing the Name of Departments), No S 124, 9 April 2013).

[45] Section 10 of the CFL Act provides that the Secretary has the functions and powers as conferred by a 'relevant law' and other Acts. The Forests Act, the SFT Act and the FFG Act are all included within the definition of 'relevant law': CFL Act, s 3 and Sch 1.

1. [51] Section 3 of the Forests Act provides that 'Secretary' means the body corporate established by Part 2 of the CFL Act.

[53] Forest Management Plan for the Central Highlands (May 1998), published by the Department of Sustainability and Environment. It was agreed at trial that the plan remains operative despite it providing that it would 'apply for ten years' and yet more than ten years have elapsed since it was published: Reasons, [217].

[60] See [24] above. Schedule 2 to the FFG Act. The LBP is also listed as an endangered species in sch 1 of the Endangered Species Protection Act 1992 (Cth).

1. [62] Department of Sustainability and Environment (Vic), Flora and Fauna Guarantee Action Statement #62: Leadbeater's Possum Gymnobelideus leadbeateri. Although the LBP AS was republished in 2003, five years after the publication of the plan, this does not give priority to the LBP AS because its terms show that it subordinates management actions to the plan. See [113] below.

[63] Department of Sustainability and Environment (Vic), Flora and Fauna Guarantee Action Statement #192: Loss of hollow-bearing trees from Victorian native forests and woodlands (the 'HBT AS'). Reasons, [105].

[64] Reasons, [106]. See Code cl 2.2.2.

[72] The number 12 was based on an early finding of Professor Lindenmayer that the population of LBP in a particular area has a linear relationship with the number of HBT until it plateaus at about 12 HBT (11.3) after which the population of LBP tends not to increase. Reasons, [171]. See the 1988 report, referred to at n 99, 352.

[74] Indeed, as his Honour noted, 'mixed aged forest where the oldest class is mature necessarily means forest which comprises regrowth mixed with mature trees, because trees younger than mature are regrowth': Reasons, [150]. See [97] below.

[75] See [70] below.

[82] At the time the plan was made, the relevant Department was the Department of Natural Resources and the Environment, a predecessor of the Department of Sustainability and Environment mentioned above.

[86] The 'reserves' are separate from the Zone 1A habitat: See further below at [69].