By Gus Elands
For many years there has been a public misconception that rainforest in NSW is "safe" from forestry activities such as roading and logging. However, State Forests (formerly the Forestry Commission) continue to allow roading and logging that will heavily disturb rainforest.
Roading through rainforest gives access to loggable hardwood stands (mainly eucalypt). This basically constitutes clear-felling a strip up to 18 metres wide, which exposes a rainforest to damaging factors such as weed intrusion, feral animals, wind, soil erosion and increased solar radiation and fire regimes (NPWS 1979).
These can all lead to permanent changes in the vegetation. The rainforest trees damaged in roading operations are allowed to be removed and processed as "salvage" logs.
Two main factors allow the logging of rainforest: an inadequate definition of rainforest and the incorrect application of this definition.
State Forests define rainforest as having: a generally complex structure; a mixed composition of typically moisture-loving trees; a presence of unusual life forms; an absence of eucalypts and typical associates except as old growth emergents from an earlier forest. (The emergents are also termed sclerophylls or hardwoods.)
According to this definition, the presence of old growth emergents does not preclude a forest being rainforest. However, recent work by the North East Forest Alliance and National Parks and Wildlife Service has shown that if an area has more than 20% "canopy cover" of emergents, then State Forests will not classify it as rainforest.
Even if State Forests did use their definition properly, it would still be inadequate because' it does not specify a "closed canopy". Many ecologists agree that a closed canopy is a fundamental characteristic of rainforest. Because of this inaccuracy on the part of State Forests, the area of protected rainforest in NSW is being contracted and the area of easily exploited "moist hardwood" forest expanded.
Throughout the state there are many areas being logged that contain this type of forest: rainforest trees forming a closed canopy beneath emergents. There are also "transitional" areas that have not yet developed this closed canopy but nevertheless have the potential to do so. Both have the potential to develop into a more complex form of rainforest.
That is, in the absence of disturbance, the rainforest shade will prevent regeneration of the emergents. By allowing logging and burning (definitely disturbing factors) of so-called moist hardwood forest, State Forests are destroying the potential for rainforest species to form a more complex rainforest community.
Logging in NSW is almost always accompanied by the use of fire. The detrimental effect of fire on rainforest species is well documented. However, disturbance such as logging and fire encourages the regeneration of emergents. These emergents, termed pyrophytic, mostly require fire to regenerate. With the increase in pyrophytic species comes an increase in the likelihood of fire, leading to the formation of drier forest.
The timber industry admits that it wants maximum regeneration of pyrophytic timber species; hence a policy that favours the emergent species to the detriment of our fast-vanishing rainforests.
State Forests even manage to adversely affect the areas that they accept as rainforest when they attempt to place a boundary around them. These boundaries can only be an estimate, as forest types simply do not have distinct "lines" where they start and finish. Rather "transition" areas exist where a blending of different forest characteristics takes place.
State Forests base their forest type boundaries on interpretation of aerial photographs. Recent aerial photographic interpretation by NEFA has shown that State Forest maps can under-represent rainforest area by 30-50%.
Simpler forest provides a "buffer" for adjacent, more complex, forest. Buffer zones are essential for the protection of rainforests, particularly against fire. NPWS states:
"Protection of the rainforest margin is very often the key to protecting the rainforest. Interference with and damage to the margin can, in some cases at least, lead to the complete demise of a rainforest stand. From an ecological point of view the 'buffer zones' ... are very much a part of the rainforest. An understorey of rainforest species in a hardwood forest and which is contiguous with a rainforest stand is very much a manifestation of that rainforest."
These rainforest buffer areas are uniquely Australian in that they support ecological characteristics of both drier pyrophytic forests (eucalypts) and fire-intolerant rainforests. The emergents within the buffer areas contain hollows that are essential for many rare and endangered fauna. The understorey contains diverse rainforest flora.
Thus through an inadequate definition and poor application of it, and a refusal to accept the importance of buffers, State Forests are allowing roading and logging of rainforest in NSW. Unless these problems are addressed, the timber industry will continue to destroy the state's biodiversity before we fully understand it.