Maruia, Okarito, Saltwater forest, beech forest, logging,
the beech scheme, rimu, Timberlands, Kit Richards, sustainable management of forests,
conservation, preservation, ancient rainforest,
all buzz-words of a vital and passionately debated topic in New Zealand in 1999 and 2000.

Some more are; sustainability, Resource Management Act, the West Coast Accord,
Labour, Minister of Forests, Hodgson, Clark, election mandate, city greenies, nfa, Native Forest Action,
F&B, Royal Forest and Bird, destruction, clearfelling, helicopter logging, modelling.

This is a paper from the Royal Forest and Bird Protection Society Inc, from one of their web-sites.
Readers should compare the statements with equivalent statements in other, more clearly scientifically-based papers on this site,
and Dr Euan Mason's pages from Christchurch.

The myth of sustainable beech management

An ecological assessment of

Timberlands’ beech scheme plans

By the Royal Forest and Bird Protection Society

 

Executive summary

Conservation assessment

The Department of Conservation (1997) has identified 92 % (or 120,829 ha) of the 132,000 ha) of the indigenous forests controlled by Timberlands as having "high" or "medium" conservation values deserving protection under DoC’s national criteria for forest protection, virtually all being the high priority low altitude ecosystems. Logging will destroy or seriously degrade those values. The beech scheme involves 75% of the forests managed by Timberlands.

Impact of logging

The plans establish "permissible" logging levels using a logging and management model prepared for tropical forests. In the absence of any research base, a substantial "leap of faith" is required in applying the model to New Zealand conditions. The plans understate the contribution which logging, new roading and clearings makes to habitat fragmentation and reducing the presence, abundance and distribution of wildlife.

Token reserves

Some small areas are proposed to be set aside as reserves. In the Maruia Forest the reserve areas include limestone bluffs and outcrops which are too steep to log without major erosion problems and have difficult access for logging crews, rather than areas which are important for birdlife.

Natural forests into plantations

Parts of the Paparoa and Grey valley beech forests, comprising a substantial part of the beech scheme total area, have been logged in the past and are now regenerating. Production thinning is proposed to remove up to 12 % of the standing volume of the forest to improve timber quality. Production thinning will turn beech forests in beech plantations, changing their natural structure, species composition, and growth regime.

No commitment to predator control

Timberlands’ public relations material gives the strong impression that the company will fund extensive predator control from its logging operations. The beech scheme plans, however, include no commitments to any active predator control programmes even though commercial logging has already begun in the Maruia forests.

Impact of roading

Extensive new roading is proposed. Some 30 km of new roading and 22 new landing sites are proposed in just two of the four blocks in the Maruia forests. (Maruia SM Plan p 64). New roading will fragment now intact habitat and degrade areas with high conservation values.

Impacts on wildlife

The beech forests provide outstanding habitat for native wildlife. No monitoring is proposed of the impacts of logging on the wildlife values of the Maruia forest (Maruia SM Plan, p 89). This would enable Timberlands to avoid acknowledging the impacts on birdlife. Riparian vegetation along streams less than three metres wide will be logged. The impacts of this on aquatic ecosystems and natural character are poorly described.

Impacts on forest ecosystem

The plans and prescriptions pay little attention to the effects which removing thousands of logs annually will have on nutrient capital, nutrient cycling, and on soil organic matter. Log removal is a major change in the natural forest dynamics and has the potential for significant adverse effects on ecosystem functioning.

Public not consulted

The company claims that "there has been widespread public consultation at every stage " (Overview p xiv). It has consistently refused to make available its draft management plans or any of the reports and wildlife and other survey reports on which they are based. Commercial scale beech logging has begun in the Maruia forests without any independent scientific or public assessment of the beech management plans or any opportunity for public consultation as promised under the West Coast Accord.

Beech scheme yet another native forestry experiment

The scheme repeats the discredited "suck it and see" experimentation done by the NZ Forest Service with such abortive results in the selective logging and clear-felling of West Coast rimu forests. "Selective logging" has just been replaced by "selection harvest". The research needed to provide a solid foundation for Timberlands’ claims of "sustainable management" has not been done. The beech scheme would be a huge experiment.

 

The major flaws and gaps in Timberlands’ beech management plans

Forests with high ecological values proposed for logging

The beech/rimu scheme targets forests with important ecological values. More than 41 per cent of Timberlands’ forests and 92 % of the Maruia forests where beech logging has begun are pristine, unlogged forest.

The Department of Conservation (1997) has identified 92 % (or 120,829 ha) of the 132,000 ha) of the indigenous forests controlled by Timberlands as having "high" or "medium" conservation values deserving protection under DoC’s national criteria for forest protection. Logging will destroy or seriously degrade those values. The beech scheme involves 75 % of the forests managed by Timberlands.

Less than 15 % of New Zealand’s (pre 1840) lowland forests remain. Virtually all of the forest being logged or proposed for logging by Timberlands is lowland forest on land under 700 metres in altitude.

The Department of Conservation (1997) has said, "The most important conservation imperative for the survival of threatened species and representative ecosystems on the West Coast is the protection and restoration of low altitude ecosystems, and especially those which link or buffer existing protected natural areas."

Timberlands recently began commercial beech logging on a "trial basis" in the red and silver beech forests of the Maruia Valley. These are some of the most ecologically important of the beech and beech/ podocarp forests that the company manages. They have been described by the Wildlife Service (1981) and the Department of Conservation (1997) as being "outstanding wildlife habitat" because of the abundance and diversity of native birds. Timberlands own wildlife surveys confirm their high wildlife values:

"South Island robin and parakeet numbers are higher than in most other areas surveyed in Westland." (Maruia SM Plan , p 28).

"The survey for birds and bats made during 1996 found significant populations of kakariki, robins, tits and rifleman in the Maruia Forests." (Maruia SM Plan , p 89)

Threatened species present in the forests include: long tailed bats, South Island kaka, New Zealand falcon, blue duck, weka and kea.

Larger older trees are disproportionately important for hole nesting species such as kaka and kakariki for feeding and nesting and as roosting sites for bats. In Fiordland beech forests 40 % of parakeet nesting observations occurred in trees between 70 cm and 110 cm in diameter with another 46 % in trees greater than 110 cm dbh. The plans propose logging red beech trees up to 110 cm in diameter, effectively removing many of the large old trees.

Timberlands has not identified the key ecosystem attributes and the essential ecological processes needed to maintain these in either the Overview Plan or the Maruia Prescriptions, as the Parliamentary Commissioner for the Environment recommended (PCE, 1995 at p 83).

The plans understate the contribution which logging, new roading and clearings makes to habitat fragmentation and reducing the presence, abundance and distribution of wildlife.

Token reserves

Some small areas are proposed to be set aside as reserves. However, Timberlands has ignored a key principle of reserve design in establishing "representative" areas and focused instead on only seeking to protect what is "rare or unique." It claims that its research consultants have not identified any areas which are "rare or unique within the beech scheme areas."

In the Maruia Forests, the reserve areas include limestone bluffs and outcrops which are too steep to log without major erosion problems and are difficult for logging crews to access, rather than areas which are important for birdlife.

Nearly half the timber in forests is low grade industrial wood

Beech logging produces large volumes of low grade wood because of internal rot and fungal damage associated with the presence of native pinhole borer beetles. In the Maruia forests only 54 % of the red, silver, and mountain/black beech trees on average will produce merchantable sawlog timber. (Maruia SM Plan p 52). The remainder are "industrial logs" only suitable for low grade uses such as fibreboard. "Industrial wood" is what would once have been called chipwood.

Major flaws in sustainable management model

The plans establish "permissible" logging levels for sawlog extraction for individual beech species using a logging and management model prepared for tropical forests. The model relies on continuous recruitment where new seedlings establish, survive and grow to become small trees.

In the absence of any research base there is no certainty that the model and the assumptions which it contains about recruitment apply to New Zealand beech forests. A substantial "leap of faith" is required in applying the model to New Zealand conditions.

The model is an equilibrium based model which assumes that mortality = growth and that this is true for all species. There is little actual data on mortality and growth from permanent plots in beech forest to substantiate this.

The matrix model used to determine annual growth increment and the timber volumes which can be extracted assumes exponential growth rates in remaining trees. There are no research trials using similar forest types to those proposed for logging which establishes conclusively the actual (timber) and biomass productivity over a given area of beech forest. Without this information, the accuracy of the model is unknown.

The growth rates, mortality rates, composition and structure of beech stands is likely to vary considerably across the forests Timberlands manages. Timberlands’ extraction rates are based on crude average growth rates for broad tree diameter classes rather than site specific protocols. Logging on the basis of an average growth rate for a tree diameter class is likely to result in considerable "over-cutting" on some sites and "undercutting" on others. Use of an average growth rate is also inappropriate because stem numbers are unevenly distributed through each diameter class.

Using site specific protocols would better recognise natural forest dynamics. The current model fails to do this. The failure to state the extent of the variability in the growth rate data which the model is based on is a major short-coming.

"Improvement felling" will more than double the number of trees felled

"Improvement felling" is intended to increase future timber yield. It will substantially increase the number of trees felled and impacts of logging.

In the red and silver beech forests of the Maruia Working Circle, for example:

"The improvement fellings of defective trees will be selected by the principle of taking the worst first, which over long time periods should lead to an enhancement of the overall timber quality within the forest." (Maruia SM Plan, p 52)

"Controlled numbers of defective poles and small trees will be felled within and between felling sites; a process termed "improvement felling."

"Improvement fellings will be subject to standard forest hygiene practices and left on the forest floor." (Maruia SM Plan, p61)

"Felling to waste a percentage of defective stems , < 30 cm DBH will occur at each harvest site and between sites within the operational area. The aim of improvement felling is to enhance the growth, productivity and survivorship of better quality poles and small trees. To achieve this, competition will be reduced through the manipulation of the spacing and number of sapling and poles…" (Maruia Operations Plan, p 22).

In the Maruia forests, improvement felling could involve felling an extra two trees and leaving them to rot in the forest for every sawlog extracted. This will significantly increase the scale of forest disturbance. The impacts of this have not been examined.

The trees logged for "improvement felling" are on top of Timberlands’ "permissible harvest" which the Plans set for each working circle and which Government sets for the scheme as a whole.

Effects on forest diversity and structure unknown

The logging prescriptions claim to copy natural disturbance regimes by felling groups of at least 2 and up to 10 trees. Most natural canopy gaps in beech forest result from the death or collapse of individual trees. Larger gaps and more light reaching the forest floor are likely to change the species composition at different levels in the forest.

Logging will increase disturbance by an unknown factor. The effects of this additional human induced disturbance on top of natural disturbance events (such as windthrows) on forest growth, structure, health and habitat values are not discussed.

Insufficient research information is available to substantiate the claim that logging "mimics" natural processes. If this was to happen then trees should be taken proportionally from size classes in a pattern which replicates natural processes. It is proposed to take a percentage of each age class. No information is provided to suggest how this percentage was arrived at and what relationship it bears to natural mortality.

Some research has been done on the structural diversity and dynamics of red/silver beech terrace forests in the Maruia Valley. Little information is available for other species and sites in either the Maruia or Grey Valleys or Inangahua area.

Hard beech is a predominant element of the Granville and other Grey Valley forests. Little is known about the population dynamics of hard beech and how hard beech interacts with other species. This knowledge gap means there is little basis for Timberlands’ claim that its logging regime will maintain compositional and structural diversity of the forest. Considerably more information is needed on forest dynamics on a site by site basis over all of the Timberlands’ estate before such a claim could be made.

Little is known about the impacts of logging on lower plants such as ferns and mosses. These have not been investigated or described.

Natural forests to be thinned for beech plantations

The Plans propose intensive thinning of previously logged and regenerating beech forest which comprises 59 % of the beech and beech/podocarp forests managed by Timberlands. Parts of the Paparoa and Grey valley beech forests have been logged in the past and are now regenerating. Production thinning is proposed to remove up to 12 % of the standing volume of the forest.

Production thinning will turn beech forests in beech plantations, changing their natural structure, species composition, and growth regime.

No firm commitment to active predator control

Timberlands’ has repeatedly blamed predators rather than habitat loss for the decline of native species such as kaka and kiwi. Its public relations material gives the strong impression that the company will fund extensive predator control from its logging operations. The beech scheme plans, however include no commitments to any active predator control programmes even though commercial logging has already begun in the Maruia forests.

Red deer, pigs, and goats are present in the Maruia forests with pigs abundant in parts but no control beyond recreational hunting is proposed. Feral cats are probably present. No control is proposed. (Maruia SM Plan , p 68-69). Stoats occur. No immediate control of stoats is proposed unless a small research programme undertaken over the next 10 years yields positive results. Whether the research itself proceeds appears reliant on obtaining funding from other sources (Maruia SM Plan, p 89).

There are no proposals to control wasps even though their biomass is thought to exceed the biomass of bird species. No comprehensive possum poisoning programme is proposed. Possum control will be limited to unidentified "hot spots" and no details are provided on the extent or location of known "hot spots".

The prescription contain no clear commitments to undertake predator control. The company’s intentions are expressed in general terms which are difficult to enforce, e.g. "Control over feral ungulates (i.e. deer, pigs, goats) will be investigated where recreational efforts are insufficient (Maruia SM Plan, p 68).

New roading contributes to habitat fragmentation and loss

Extensive new roading is proposed. Some 30 km of new roading and 22 new landing sites are proposed in just two of the four blocks in the Maruia forests. (Maruia SM Plan p 64). Roads create new forest edges, increasing the light reaching the forest floor and the air temperature and reducing the humidity. This can cause changes in the diversity and composition of plant and animal species. Roads also provide a corridor for weed (e.g. broom and Himalayan honeysuckle) and pest spread into the forest interior. The impacts of this have not been assessed or stated.

To reduce soil conservation impacts, roading is proposed for valley floors rather than ridges. Alluvial mining damage is also concentrated in these areas. Valley floors forests on deeper, more fertile alluvial soils often have the largest trees and high bird numbers. Remaining valley floor forests managed by Timberlands have high ecological values because they are under-represented in the conservation estate because of past clearance for farming and settlement. New roading will fragment now intact habitat and degrade areas with high conservation values. Spoil from new roading can increase sediment run-off and contribute to sedimentation in waterways.

Impacts on nutrient cycling and soil organic matter

The Parliamentary Commissioner for the Environment (PCE, 1995) identified information on nutrient cycling as being a major gap in knowledge about beech forest ecosystems . The PCE report recommended that the impacts of log removal on soil nutrient status and cycling be investigated. The plans and prescriptions pay little attention to the effects which removing thousands of logs annually will have on nutrient capital, nutrient cycling, and on soil organic matter.

Log removal is a major change in the natural forest dynamics and has the potential for significant adverse effects on ecosystem functioning, particularly in the hard beech forests of the Grey Valley where soils are acid, strongly weathered, leached and of low fertility. The impacts on soils are not considered in any detail.

Logging will reduce the soil mixing which occurs through pit and mound formation from natural windthrows. No monitoring of changes in soil structure and nutrient availability is proposed.

Riparian protection only applies to large streams

West Coast streams are a strongholds for native galaxiids such as banded and short jawed kokopu which have disappeared from many other areas as a result of forest clearance and stream modification.

Streamside management zones in which no logging will occur are only provided for on rivers and streams with a bed width of more than 3 metres. Riparian vegetation along smaller streams will be logged. The impacts of this on aquatic ecosystems and natural character are poorly described.

Monitoring

The Parliamentary Commissioner for the Environment (PCE, 1995) recommended the establishment of "a network of Permanent Sample Plots" throughout the range of ecological variability within the Timberlands’ estate to measure "the effects of stand manipulation on the floral and faunal characteristics of the forest ecosystem and on soil characteristics."

The prescriptions fall well short of this in only proposing to monitor tree species at the working circle level Other ecological parameters will be monitored at other locations but the content, scale, extent, and detailed of proposed monitoring is not clearly stated. Without detailed prescriptions, Government and MAF face a difficult task in determining whether the prescriptions have been followed.

No monitoring is proposed of the impacts of logging on the wildlife values of the Maruia forest (Maruia SM Plan, p 89). This would enable Timberlands to avoid acknowledging the impacts on birdlife.

The failure to provide for monitoring of changes in soil structure and nutrient availability is a flaw. The general lack of information about the details of the proposed monitoring programme is of concern.

Lack of public consultation

The company claims that "there has been widespread public consultation at every stage " (Overview p xiv). It has consistently refused to make available its draft management plans or any of the reports and wildlife and other survey reports on which they are based. Commercial scale beech logging has begun in the Maruia forests without any independent scientific or public assessment of the beech management plans or any opportunity for public consultation as promised under the West Coast Accord.

Sustainable management – a huge experiment

The scheme repeats the discredited "suck it and see" experimentation done by the NZ Forest Service with such abortive results in the selective logging and clear-felling of West Coast rimu forests.

The research needed to provide a solid foundation for Timberlands’ claims of "sustainable management" has not been done. There are huge unknowns in beech management over an 80 to 100 year rotation. Trial data from the Timberlands’ forests is not available for this length of time. The variability in regeneration, recruitment, and growth rates throughout the Timberlands’ managed forests and over this length of time is unknown. The changes in forest structure, species diversity and habitat values caused by logging are not described.

Timberlands acknowledges this uncertainty :

"While careful management under the systems proposed under this overview plan will avoid problems, it is nevertheless theoretically possible that until more intense data accumulates, inflexible adherence to average conditions could over a long period of time be a problem. It could lead to a leveling of forest-site capacity. In some rare and localised cases this could be assumed to push the impacts of management beyond the bounds of natural ecological capacity of a site." (Overview, 4.4.3).

The 98,000 ha of beech and beech podocarp forest affected by the beech/rimu scheme have high conservation and recreation values. The lack of long term research data on beech management over the proposed 80-100 year rotation, the variability within the forests managed by Timberlands, the lack of information about effects on nutrient cycling regimes and the considerable uncertainties associated with beech management mean that the beech scheme is a huge experiment.

 

For further information please contact: Eugenie Sage (03) 3666 317 (work)

(03) 3371 251 (home)

Email: sage@chc.forest-bird.org.nz


Original source.