New Forest Service policies take a big step backward
Daniel B. Wheeler
dwheeler at ipns.com
Sun Apr 21 09:06:27 EST 2002
Larry Caldwell <larryc at teleport.com> wrote in message news:<MPG.172bd097bd8b0ea989a62 at news.earthlink.net>...
> In article <RwKv8.16899$3z3.1580227 at newsread1.prod.itd.earthlink.net>,
> fotoware at jps.net writes:
> > However, I have been humbled by working out here in Arkahoma. My extensive
> > western experience has little value so far in understanding these
> > eastern/southern forests. The Northwest certainly has differences as well
> > and I could be blowing diesel smoke out my ass.
> The real conservation consideration in the PNW is the soil. The land is
> generally so steep that if it is left exposed for any length of time,
> erosion will remove the soil. Southern Oregon is best compared with
> Greece. It looks a lot like Greece looked 3000 years ago, and the
> climate is very similar. Today, there is no topsoil left to support
> forests in the mountains of Greece. Pasturing animals, which suppressed
> seedling reproduction, combined with fires and hoof action, completely
> removed the soil from the hillsides. All that is left are bare rocks
> bleaching in the sun. It will take thousands of years for those
> mountains to recover, if they ever do.
Any serious consideration of forestry must include soil. After all,
soil was one of the four requirements for growing trees as discovered
by Gifford Pinchot.
I think soil retention is what you are talking about above, Larry. And
productive soils are largely defined by the number of soil fungi
included in them, at least according to Dr. David Perry, a soil
scientist at Oregon State University.
On steep slopes, some forms of fungi actually tie soil particles
together, along with rock, trapping them in a fibrous net. These fungi
are called Hymenogasters, and are also found on more gentle slopes,
but with less frequency. Fruiting bodies are generally small, less
than 1 inch in diameter, and found fruiting within these mycelial
mats. Many soil-building organisms are dependent on the mycelium for
food, and it is their feces which create soils on these slopes.
They are also insanely difficult to identify. The spores are all
nearly the same size, but they do have minor variations. Since most
have not been cultivated, their host requirements are not known. What
works for one stand of Douglas-fir on nw slopes on Mt. Hood do not
necessarily translate to the same areas on Mt. Shasta.
I would also point out one difference between Greece and PNW: the base
rock is entirely different. Most Greek soils are very calcarious.
Those which are not are very old rock. These rocks are considerably
different from the new volcanic soils found in the PNW, and have much
different soil pH.
> For the long term health of the land, it's not particularly important to
> focus on the trees. Trees grow. 12,000 years ago, there weren't any
> montane forests in the PNW. When the glaciers retreated, the forests
> advanced right on the edge of the ice. If you leave any second growth
> patch alone for a century, you will have old growth again. There have
> been preservationist demonstrations over patches of woods that burned to
> mineral soil in the 1880's (the China Left sale), and even the 1930's
> (Tillamook State Forest - Tillamook Burn). There have even been
> demonstrations over O&C lands that have been logged 3 and 4 times since
> Grover Cleveland took them back from the railroads. O&C lands are a
> special case, since the old steam engines used to set them on fire every
> summer. They are pretty much poster plots for frequent burning as a
> forest management tool.
It is true that few forests existed during the last ice ages. But
fossil evidence also shows that the Dawn redwood probably developed in
the PNW. I personally know of fossil beds between Lebanon and
Brownsville rich with Dawn redwood, which probably died out long
before the last ice age. Similarly the climate has changed
dramatically in geologically recent years in the PNW. What was once a
great inland lake in Central Oregon supported palm and magnolias:
trees which would not typically be associated with ice sheets.
> What we need to do is focus on the soil. Some plots should never be
> logged, no matter what is growing on them. You might be able to reforest
> once or twice, but eventually the soil will be so depleted you will be
> staring at a rock face.
As long as re-forestation was rapid (less than 2 years as if often the
current case, and preferably less than 2 months) some of those sites
could be logged. As you mentioned, soil depth in these areas is
limited and must be conserved where possible. Using at least some of
the logging debris as chips, humus, or cross-wise debris barriers on
the steeper slopes would certainly help. But the cost is prohibitive
and most logging companies are more interested in making a buck than
in long-term forestry practices.
> This has already happened many times. Other
> plots can stand indefinite intensive forestry with no damage.
That has not been proven, and is probably false. The mycorrhizal fungi
found by Dr. Helen Gilkey (my botany instructor from Oregon State
University) were collected and preserved from the area near Philomath
and the Mary's River drainage in the 1920-40 period. Many of these
fungi have not been found since the areas were logged. (Philomath has
a larger proportion of millionaires, btw, than most of the US. Most of
that wealth was directly related to logging.)
Without those mycorrhizal fungi the ability to create old-growth
forests in the future _may_ be seriously compromised. At this date, no
one is certain.
I remember Helen telling me that she could walk into a forest and find
two adjacent Douglas-fir in that area, both of which were healthy. One
would have a high nitrogen content as determined by needles. The other
would be nitrogen poor. Nitrogen is one of the important growth
factors in growing trees. She never knew what two seemingly healthy
trees growing nearly side by side would have such different nitrogen
contents. It wasn't until after her death that researchers in BC
discovered some mycorrhizal fungi actually share nutrients. And she
missed the data developed in the late 1980's at Oregon State
University that many mycorrhizal fungi are also associated with
> If you
> limit the size and spacing of clear cuts, the old ecosystem will
> rapidly colonize the new growth. Thousands of years of forest fires have
> evolved PNW forest species to do exactly that, easily and efficiently.
> As long as the soil remains, you can grow anything you want.
When reforestation does not take place within 6 months after logging,
mycorrhizal fungi die out quickly. There are clearcuts in the Winema
National Forest which have not regenerated, even though they were
surrounded by old-growth Noble fir (the predominant species in the
area). Mike Amaranthus has noted that when soil from under the old
Noble fir was transported to holes where new seedling trees were being
planted, the seedling survival rates dramatically increased from near
zilch to something over 50%. Unfortunately the mycorrhizal associated
with old-growth trees are not the same as those found with seedling
trees. The only remaining trees growing and healthy in these clearcuts
are along the perimeter of the clearcuts, where mycorrhizal can be
translated by voles and other animals.
Thus mycorrhizae have been shown not just important in these areas,
but essential to future tree growth.
That's why it is so important to manage for ecological species. What
appears to be an insignificant salamander or slug may, in fact, be the
dispersal vector for these important mycorrhizal fungi. Thaxterogaster
are some of the few mycorrhizal fungi I know from old-growth Noble
fir. They are toxic to most mammal species, but dispersed by slugs. As
the stands mature, they become important sites for production of
Cantharellus tubaeiformis (Yellow-foot chanterelles), which can be
economically significant in forests. Unlike tree harvest, Yellow-feet
may produce annual crops (sometimes bumper crops as this past year has
demonstrated) of economically important fungi.
Daniel B. Wheeler
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