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The Trail Companion
Late Winter 1999
The 1999 San Francisco Peninsula - South Bay
Restoration Workshop
by Geoffrey Skinner
If you have spent any time in California
wildlands, you have undoubtedly run into yellow star
thistle, pampas grass, broom, or any of a host of
invasive non-native plants. These plants tend to
displace native plant species, changing the structure
and function of our local ecosystems, and resulting
in a loss of genetic diversity or a decline in other
"ecosystem services" upon which we and the animals
that inhabit the ecosystems depend. On a more
immediate level, a number of these invaders,
including yellow star thistle and bristly ox tongue,
tend to be prickly to walk through. The SF Chronicle ran a front-page
article on the yellow star thistle invasion in
mid-January and an article or two have appeared in
the Trail Companion in the recent past. Statistics
show that over a thousand exotic species of plants
have been introduced to California since the first
visits by Europeans, with the number increasing
exponentially over most of that time, though records
of the California Dept. of Food and Agriculture
suggest that the increase is beginning to slow
(Fremontia, v. 26, no. 4 (Oct. 1998), p. 4). Some
species were introduced intentionally, others arrived
accidentally-perhaps on horses hooves or in feed
bags. Human activity has encouraged exotic species to
spread throughout the state. For some of the
invaders, El Niño and other
naturally-occurring disturbances (perhaps exacerbated
by human-caused global climate change) boosted their
numbers tremendously. Even on our trail projects, we
have noted that any disturbance-particularly in
grasslands-will result in an explosion of weeds. Next
time you walk down a grassland trail, notice the
plants growing along the trail. Often these are the
first places that yellow star thistle and other
invasive plants will appear. The human impact on the
ecosystem extends further than weeds, of course, with
a tremendous loss of habitat as we have built our
cities and roads. The weed population is not the only
one to increase exponentially.
Peninsula and South
Bay land managers and restoration professionals and
volunteers gathered at Skyline Ridge Open Space
Preserve on Jan. 29th for the 1999 San Francisco
Peninsula - South Bay Restoration Workshop. The
workshop, sponsored by Bay Area Action, California
Native Plant Society, Magic, Midpeninsula Regional
Open Space District, and Native Habitats, marked the
first time the participants had gathered with a
regional focus, although many had met in other
settings. The organizers saw that many of the
problems facing land managers aren't confined to a
single jurisdiction whether the issue is invasion of
yellow star thistle, Harding grass, and other weeds,
or siltation threatening aquatic fauna. These
problems tend to be regional in scope; eradicating
Italian thistle in a state park won't be possible if
the open space preserve next door is full of more
thistle.
While future meetings
may focus on technical aspects of restoration, this
first meeting addressed issues of a general nature,
with the keynote address by Jake Sigg, State
President of the California Native Plant Society
(CNPS), Chair of the CNPS Exotics Committee, and past
president of the CNPS Yerba Buena Chapter, who spoke
on his personal odyssey of going from an
indiscriminate gardener to a passionate
restorationist of native plants. Sigg stressed that
restoration work is as much or more about restoring
ourselves as about restoring the land. Environmental
degradation mirrors exactly the degradation of our
society. Other speakers were Ken Himes of the CNPS
and Friends of Edgewood Park, who spoke on the plant
communities of the Santa Cruz Mountains and South Bay
and CNPS restoration efforts, and Alan Launer of the
Center for Conservation Biology, Stanford University,
who spoke on rare, threatened, and endangered animals
of the bioregion.
After the
presentations, participants broke into smaller groups
to discuss successful restoration strategies and
misfires; finding, managing and training volunteers;
and communicating the values of restoration to the
public. Georgia Stigall of Native Habitats and the
CNPS, one of the organizers, has posted highlights
from each group discussion on the Arastradero
Preserve website (http://www.Arastradero.org).
Jodi Isaacs, Resource Management Specialist with
MROSD, and Paul Kephardt, of Rana Creek Habitat
Restoration, led a field trip to Russian Ridge Open
Space preserve to examine three techniques used to
manage grasslands: mowing, grazing with goats and
sheep, and burning. Isaacs also discussed biological
controls and spot application of herbicides. MROSD is
in its second year of grassland management on Russian
Ridge, with control of yellow star thistle the main
target and Harding grass a secondary target. A seed
drilling program using a variety of native species
following a burn looks promising, but Isaacs warned
that it is too early to draw firm conclusions.
Preliminary findings indicate that no one method
alone will accomplish their goals.
If you are interested
in learning more about local or statewide restoration
work, you may wish to visit the Native Habitat
website (http://www.nativehabitats.org),
which links to many groups involved in restoration
work. Our own activity schedule also lists a few of
the local restoration events, but is not
comprehensive. In addition, the Trail Companion will
continue to report on restoration issues,
particularly as they relate to trail projects. Of
particular interest may be the restoration workdays
at Arastradero Preserve sponsored by Bay Area Action
on the second and fourth Saturdays of each month (see
the Arastradero website for details); we expect to
work with BAA for California Trail Days on April 26th
for a reroute of the Acorn Trail.
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