>I'd like to reply to Brett's comment that management can be controlled, but >natural disasters cannot. First, not all disturbances are "disasters" and what >is or is not a disaster has a strong anthropocentric component that is not >within the scope of this discussion (or maybe it is - but I'll leave that to >others to debate and stick to disturbances). And some disturbances that might >be classified as disasters are the result of management activities - some very >well-intentioned, such as suppressing fires. > > The 1994 Tyee Fire (Wenatchee NF) burned 142,000 acres. The burn spanned >vegetation from shrub-steppe to subalpine forest, but most of the area burned >was in dry pine forest that (excuse this - I don't know how to format the DG) > >historically burned every 3 to 6 years for the past 500 years (determined from >tree ring analysis of wedges cut from these trees), with the exception of the >last 100 years during which fires were suppressed. The change to the natural >disturbance regime, while initiated by timber interests, led to vegetation >characteristics that made spotted owls (and many wildlife biologists and >environmentalists) happy. Open stands of pine were converted to multi-layered >stands of pine, Douglas-fir and true firs. Just before the fire, stands had a >2 to 7 fold increase in density over historical conditions. Fuels were >connected vertically and horizontally across the landscape. Yes, the weather >conditions were somewhat anomolous - but over several centruies, the PNW DOES >have those "blocking highs" in the Pacific that make for severe fire years. >Anyway - the Tyee burned and so did 9 owl nests and the ecosystems that the >nests were in. The resulting landscape will not support owls for al long time >(and maybe didn't historically...). > >All this background to explain why I think we need to evaluate inherent >disturbance regimes *and the vegetation characteristics that resulted* before >we determine through the courts just how big a clearcut should or shouldn't be. >In some forests, perhaps clearcuts are not appropriate, but perhaps they ARE in >other forests - some of our biodiveristy (not just game animals, but >butterflies too) requires open areas. And, this diversity evolved under >vegetation characteristics that resulted from the disturbance regime. > By the way, the Hubbard Brook study you referred to indicated, I think, >that about 3% of site nutrients were stored in the *boles* of trees - that part >usually taken off-site during harvesting. If branches, needles/leaves, bark >can remain onsite (not at a landing) loss of nutrients is significantly >reduced. And the loss of nutrients by fire *can* be very high - both from the >burn itself (it goes into the atmosphere and doesn't remain on site) and from >erosion following rain on devegetated slopes. If you want to challenge >harvesting effects, I suggest that soil compaction, not nutrient depletion, is >a more appropriate target in *some, not all* temperate forests (the tropics are >another story). > >AND - I would be the last person to condone logging significant old growth >forests west of the Cascades crest, even though I strongly support the use of >timber (a renewable resource) over steel and other building materials that, to >me, pose a greater "threat" to the health of the planet. > > >Ann Camp I'm interested in your fire history comment can you give me a published reference to this interpretation? We have a similar fire history in some of our eucalypt forests Thankyou _____________________________________________________________________ Dr John Banks Email: John.Banks@anu.edu.au Forestry Dept tel: +61 62 249 3632 Australian National University fax: +61 62 249 0746 Canberra 2601
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