From hemenway@jeffnet.org Mon Aug 2 17:37:44 1999 Date: Mon, 2 Aug 1999 11:26:02 -0700 From: Toby Hemenway To: permaculture@envirolink.org Subject: Re: questions regarding succession and climax states (un) leash wrote: >After doing a little reading on Indigenous California Practices, I'm a little >confused regarding permacultural principles of climax and succession. > >Is our goal to foster a climax state? The concept of climax has been largely abandoned by research ecologists, who now believe (as I do) that it rarely exists in nature. It was once thought that all ecosystems mature toward some inevitable, final plant community, like western hemlock in the NW, beech in parts of the east. The idea was that shade-tolerant species would dominate. But real ecosystems are far too dynamic to allow a single community to predominate, as disturbance and the resulting "patchy" landscape is the actual situation, caused by incessant disease, fire, wind throw, browsing, and on and on. Native American burning kept much of North America in a mixed-sucessional state (open parkland with old trees but young understory) in part because this, as unleash noted, is ideal habitat for large game. Old closed-canopy forests are relatively depauperate in large fauna (sorry: big dark woods ain't got many animals), so they don't support many humans (unless they farm elsewhere), either. Permaculturists are striving for multi-functional landscapes that are site appropriate and support humans and other species, which can mean many different things. But you're going to run into trouble if you want to re-create "natural" landscapes and processes. What is a natural landscape? For example, much of our property here in Oregon is full of 30-100 year-old doug firs, growing beautifully thick and tall. That's a major successional stage here now, but it's a direst result of fire-suppression by humans. However, dotted amongst and overtopped by these firs are huge, 100-300 year-old open-form oaks and madrones. These are the remnants of native burning, stopped in the 1850s by whites. It used to be parkland. Both these landscapes are the result of human intervention, so which is natural? You might ask what preceded native burning. You'd probably find yourself at the edge of a glacier in a birch/aspen forest 10,000 years ago. Is that the natural landscape? Not any more. And if we don't suppress fires, or clear out the fire burden, it will all burn catastrophically and then take several centuries to reach some sort of patchy, mostly closed-canopy landscape that will support very few humans. Is that natural? I think we're stuck with learning, as best we can, how all this works, and trying to foster landscapes that support humans and everybody else. Maybe if we got our population down below 1 billion we could afford to "let nature take its course" with much of the planet, but until then I think we're going to have to intervene as wisely as we can, burning or clearing here, planting there, keeping much of the planet (at least much that is now in farm, settlement, and managed forest) in various mixed-successional states so it will support us without killing off too many other species. Toby