On Fri, 19 Mar 1999, eric + michiko wrote:
>
> I use the term climax forest to mean the native stable (until fire, flood,
> landslide, logging, etc.) forest structure. As trees fall and local
> unstabilizing events occur, succession takes the area back to the climax
> forest state. Redwood forests are a good example. They may last for
> thousands of years (millions?) as redwood forests. Openings are only
> temporary, as they are always, eventually, filled in by the redwoods again.
> Some areas are not forest areas; they may be brush or grasslands, or
> wetlands, or whatever. I suppose they may also have a climax state, though
> I have never given this much though.
I believe they do. Although bogs, depending on how they were formed can
eventually, after a very, very long time become forest again. As long as
rivers or lakes stay fairly stable the wetlands and flood plains
associated with them will reach the equivalent of a climax state. I'm
going from twenty year old memories on this though so can't provide
references. There are some really interesting bogs in Southern Ontario. I
visited one on a highschool field trip over twenty years ago. They are
formed in small lakes called Kettle lakes, I believe,
formed during glaciation. If they have a substantial spring feeding them
they stay lakes, if they have only a small supply of new water they
gradually over thousands of years become bogs. They very elegantly and
clearly show the succession from lake to bog to forest along their edges.
>
> As I mentioned, I think repeated logging, which can deplete the soil, can
> make it difficult or even impossible for the same forest species to come
> back. Eventually the land may support another forest, although not
> necessarily the same species. Perhaps the area may be grassland, brush (or
> desert) for a long time. I see hills in California that I'm sure were once
> forested. They were logged during the Gold Rush, the building of the
> railroads and the building (and rebuilding) of San Francisco. They were
> used for cattle grazing for so long after that that the forest never came
> back (at least so far). But all of this does not change "the nature of a
> climax forest" (semantics? perhaps). They still exist and function as
> before, although we often don't leave them alone enough.
The Algonquin Park area in Ontario is a good example of the effects of
logging. The forest there at the start of logging was a mature white pine
forest. Among the dominant animal species were wolf and moose. Very few
deer. Logged out and burned over in the 1800's it is now a predominantly
mixed deciduous forest with some white pine mixed in. Deer dominates over
moose and the wolf population though recovering was hunted almost to
extinction to preserve deer hunting for humans. Deer and moose do not tend
to coexist well because of different habitat requirements and because deer
carry a parasite usually fatal to moose. As the forest matures deer become
less common and moose more common. That's happening now. Eventually I
believe that White pine will also predominate in this area again if they
can ever get the logging completely stopped there. Eventually being about
a thousand years from now.
The Sudbury area of Northern Ontario is also very interesting to look at
in terms of the effects of logging and pollution and succession, but I
can't take too much more time from the
endless unpacking so that'll have to wait unless anyone with more time
knows that story. It's been nice to see the
traffic on the list over the last few weeks although I'm only now getting
a chance to read anything.
sph
Sandra P. Hoffman
[EMAIL PROTECTED]
http://www.flora.org/sandra/
