[PCA] Roadside Great Basin refugia, for all native things great and small

Craig Dremann craig at astreet.com
Wed Aug 30 12:35:20 CDT 2006


Dear Dr. Jordan and All,

Dr. Jordan's questions about insect pollinators and roadside refugia, I
tried to answer in August-September 1997, with a 3,400 mile Great Basin
Megatransect..

The Great Basin megatransect is a mile-by-mile evaluation of the native
grassland/flowering herbaceous plant cover from Sacramento Cal. via Nev,
Ut, and Colo to South Dakota, and from South Dakota via Wyo., Id., and
Nev. to Bishop California.  

Dr. Jordan's question, is anyone doing studies to determine whether
roadside refugia serve as  sources or sinks for pollinator or beneficial
insect populations, would be very useful.  I would also include relic
native plants in those roadside refugia, also.

Looking over my Megatransect notebooks from 1997, there's huge stretches
of the Great Basin where the ecosystem was grazed down to only dust and
sage/rabbitbrush, when the area was open range and at a date prior to
numerous autos on the road and roadside fences being built, i.e.
1860-1930s.

Therefore, in areas where the ecosystem was catastrophically removed
prior to fencing, then both sides of the fence are in the same ruined
condition, and no relic examples of Great Basin ecosystem, other than
sage and rabbit brush, exists in those areas.

However, there are big stretches, or at least there were big stretches
in 1997 prior to the droughts, of either good roadside relic native
ecosystem protected along the roadsides, and rarely, good stretches on
the other side of the fence also.

However, mowing didn't seem to be the biggest factor to the survival of
the roadside relics over the 3,400 route--it was the intentional sowing
of exotic perennial grasses by the State DOTs of crested wheatgrass,
intermediate wheatgrass, siberian wheatgrass, and as you go eastward,
smooth brome, dutch clover, white clover and yellow sweet clover.     

The sowing of exotic perennial grasses and other weeds along the highway
roadsides, permenantly type-convertes those areas to Russian
Steppe/European meadow ecosystem. 

Plus, when you sow in those weeds, the Great Basin ecosystem will never
have a chance of recovering that area, at least not until we purposely
eradicate the exotics we've sown, or until the glaciers come and scrape
the exotics off thousands of years from now.

In a lot of areas of the Great Basin, at least in the 3,400 miles that I
looked at in 1997, wherever road fences were built while there was still
some ecosystem to protect, the roadsides have become, by default, the
refugia for the best examples of Great Basin ecosystem along a lot of
those 3,400 miles.  

Therefore, in 2006 it would be extremely important to know and map where
all of those roadside refugia are left, and work with the State DOTs to
protect them, because these important areas also represent some of the
last remaining native seed sources for land management agencies, like
BLM, to have local genetic material to work with.

I am in the process right now, of transcribing my 1997 Megatransect data
out of my notebooks and onto the computer, and wonder if this baseline
data would be of any value to land management agencies of the Great
Basin?

Sincerely,  Craig Dremann, Redwood City, CA (650) 325-7333




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