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Retention in watersheds

Daniel B. Wheeler dwheeler at ipns.com
Wed May 22 08:56:55 EST 2002


Your location indicates an overstory of Sequoia sempervirens, with
probably Sitka spruce, Western hemlock, Douglas-fir, and perhaps other
overstory trees. (I'm guessing, here.)

The overstory in surrounding areas is important, because the slope
stabilization you seek is found in the mycorrhizal fungi associated
with these larger, established trees.

I'm guessing it will be Hysterangium species, but can't say for sure.
Hysterangium for dense, fibrous fungal "mat communities", which
stabilize even extremely steep slopes and tie-in rock, soil, and humus
layers. The mycelium forms tough threads, and the fruiting bodies
often fruit inside these mats, making harvesting somewhat problematic
as mature fruiting bodies are required for dispersal (usually by small
mammals).

I'm further guessing that your bedrock situation is mostly serpentine
or associated material (aka soapstone), which tends to slide naturally
unless something stabilizes it.

If there is little overstory, it may be necessary to re-introduce that
mycorrhizae into the area.

Finally, I wouldn't put down Ceanothus quite so much (even though it
does burn easily). Ceanothus is one of the early colonizing species
which naturally occurs in your area, and often is associated with
mycorrhizal fungi. It is suspected that at least some mycorrhizae may
survive some clearcut areas because of the woody brush, such as
ceanothus, which _may_ associate with more than one species.

So at least until the tree cover can become established, leave some of
the ceanothus (but not necessarily all of it. One clump every 10 to 40
feet should be sufficient, offering at least some biodiversity without
lending more fuel loads to the land than it can deal with.

Unless you have far more hardwoods (alder, maple, etc) introduction of
beaver will not help you much, I think. Beaver typically like more
level land that you describe, and don't care to forage on steeper land
if possible. But to survive they do need quantities of hardwoods,
because their teeth continue to grow year-round, and they _must_ be
eroded by chewing or they will eventually kill the animal. Therefore
beaver may also end up girdling redwoods near the water that  have
little or no food value for the animal. I have seen in my local area
beaver damage to Western hemlock, Douglas-fir, and many other
softwoods. Introducing them to the area without a substantial amount
of hardwoods for a food supply may be doomed to failure.

Daniel B. Wheeler
www.oregonwhitetruffles.com
"Richard McGuiness" <armich at cox.net> wrote in message news:<KUyG8.58463$Md6.1302013 at news1.east.cox.net>...
> Group,
>  I have mentioned before i was restoring a devastated watershed, a tributary
> of the Mattole here in Northern California. Road building, logging, fire and
> fire roads all set in motion a long period of slides, debris torrents, bank
> failures and other assorted lanbdscape irregularities. These have degraded
> the creek so it does not flow at all in spots in the summer. We have planted
> the slopes and riparian areas and slowed much of the gravity feed
> sedimentation. I am assured that by the time the creek is fully shaded by
> trees (not ceanothus) the creek will run year round. However, there were 19
> mapped springs on this property when we bought it and we are now lucky to
> have five. So we have been trying to figure out how to hold more of our
> far-more-than-adequate rainfall (just outside Honeydew, one of the wettest
> places in the U.S.) so the creek runs later into the heat (year) and so
> there are more uphiull watering sites for wildlife and plants, and
> eventually agriculture.
>  One of our problems has been the steepness and the liklihood that retaining
> (recharge)ponds only saturate the earth leading to slides in the winter. Our
> hand dug examples are enough to know that even a small hole on a hillside
> can cause the entire bench to fail, so location has everything to do with a
> seep. Our group would be very interested in more information as to how to
> make a larger percentage of our rainfall storable without inflicting more
> damage in the area. We need some kind of handbook for small projects,
> probably collected from antiquity and the third world or organizations
> working there. There are no retention  facilities of any kind here-what is
> appropriate and when do you have enough or too many?
>  At this time, we have 100% cooperating landowners and zero commercial
> operations of any kind on our three and a half mile creek. We cover several
> other area creeks but we want to develop a usable model. This area lies
> between Humboldt Redwoods State Park, and King Range National Conservation
> Area. Save the Redwoods helped add  Gilham Butte to these lands making it is
> a de facto wildlife corridor, )Redwoods to the Sea Wildlife Corridor,  but
> we feel taking land off the tax rolls is a "lesser of two evils" situation,
> and that restoration means recovery and not preservation. Our group works
> with private landowners in this corridor, which is the result of many small
> community actions over the years.
>   We asked California Fish & Game about beaver many years ago, and they were
> horrified. But the more I think on it, the better of an idea they are. Their
> thinking has changed a lot recently. Some other benefits accrue from beaver
> in other facets of watershed management, such as fire protection. Our fire
> jumped an empty creekbed, this might not have happened if there was water in
> it. A beaver pond widening the creek makes it even less likely. In fact, our
> national debate over how to contain wildfire, claiming all areas were
> burnt/managed by Natives, fails to recognize that the millions of beaver in
> every waterway carved the fuel loads into small areas. High humidity and
> water tables probably helped keep the fires cool and out of the crowns.
> Standing water and transpiration raise humidity, a key factor in wildland
> fires. Larger and more diverse insect communities feeding larger and more
> diverse animal populations, especially song birds. These ponds make good
> nurseries for coho and steelhead. Lowered water tables also alter or slow
> the succession of plants in a recovering landscape. A natural progression
> worked out over centuries is denied one of its most valuable resources- year
> round ground water.
>  We are being asked for our experience restoring these devastated places but
> really we need to hold more water in the watersheds to make it the kind of
> success it could be. Trees, duff, dug springs on the hillsides and pool
> digging in the creek are our main water retention tools so far.
>  We appreciate your comments, suggestions and ideas. Thanks.
> 
> Richard McGuiness
> Middle Mattole Consevancy
> Mattole Restoration Council
> Mattole Salmon Group




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