| Hopland
celebrates 50 years of rangeland research
 WHEN
the UC Hopland Research and Extension Center (HREC) was established
in southern Mendocino County in 1951, much of the focus was on increasing
sheep production. "The North Coast was the heart of the California
sheep industry," says Robert Timm, Hopland's superintendent
since 1986.
 But as the
local sheep industry dwindled and concern for the environment rose,
the center's mission shifted and expanded to include managing and
conserving wildlands. "One of the trends has been a much greater
focus on natural resources over the last 20 years," Timm says.
Hopland
is an ideal place for studying how to manage North Coast natural
resources. Located about 30 miles inland from the Pacific Ocean,
the 5,358-acre center is geographically and biologically diverse.
The rugged terrain ranges from 500 to 3,000 feet in elevation, and
has a variety of vegetation types including grassland, chaparral
and hardwood forest, as well as wetlands, Parson's Creek, springs
and vernal pools. The wildlife is equally varied, with more than
600 species of plants, 200 birds, 40 mammals, 27 reptiles and amphibians,
and eight fish, including steelhead trout.
The University
began establishing what are now called Research and Extension Centers
(RECs) in 1912 to facilitate research on agriculture and natural
resources. The 10 RECs, previously known as field stations, represent
the major crop-production and climate regions of the state, with
individual RECs specializing in tree fruit and vine crops, field
and vegetable crops, and livestock production and natural resource
management (see p. 3).
"The
REC system allows campus-based researchers the opportunity to work
in the field on problems of local and regional significance,"
says Harry Carlson, director of the REC system from 1995 to 1997
and current superintendent of the Intermountain REC, near the California-
Oregon border. "Researchers don't have to worry about disturbances
by trespassers, or about experimental complications that often occur
when research is conducted in fields privately managed for commercial
production. This is especially true of Hopland due to its large
size."
As the center
celebrates its 50th anniversary, California Agriculture features
important new and ongoing research conducted at Hopland.
A half-century of research
An annotated
bibliography based on research conducted at the HREC through 1999,
which is scheduled for publication in 2002, contains more than 1,000
entries, says UC Berkeley Professor Robert Lane, chair of the HREC
Research Advisory Committee.
"A
perusal of this compilation underscores the multidisciplinary nature
of many research projects at Hopland," says Lane, who has been
working at the center since beginning his doctoral research there
in 1970. For example, investigations of human tick-borne diseases
(such as Rocky Mountain spotted fever and Lyme disease) initiated
in 1974 have involved such disparate disciplines as acarology, bacteriology,
microbiology, virology, immunology, ecology, herpetology, mammalogy,
ornithology and molecular biology (see p. 13).
In 1976,
there were 21 research projects distributed among five principal
categories at Hopland, the great majority of which represented animal
science, range management, or entomology and parasitology. By 2001,
however, the number of projects had expanded to 37 with the emergence
of two additional distinct categories, natural resources and plant
science. "Today, projects involving natural resources science
and environmental management comprise a sizeable proportion of the
project mix at Hopland," Lane says.
Some of
the new knowledge emerging from these studies received immediate
application regionally, nationally or globally. For instance, research
conducted on anthelmintics (deworming agents) during the 1950s and
1960s benefited both the sheep industry and pharmaceutical science.
Some field studies have been designed to find solutions to current
management problems: a recent agroforestry project demonstrates
how livestock grazing and tree farming may be conducted simultaneously
to increase producer returns and limit pressure to subdivide rangeland
(see p. 37), while long-term trials with Australian clover cultivars
are providing important information on the usefulness of these legumes
to improve North Coast rangelands (see p. 60). On the other hand,
research of a more basic and long-term nature expands our understanding
of biological and physical processes in natural and human-modified
ecosystems.
Sheep breeding and predator control
While it
is no longer the primary focus, sheep-related research at Hopland
continues to provide critical insights for producers and range managers.
Hopland's sheep work includes more than 30 years of genetic research
(see p. 19). One of the main goals was to develop sheep breeds that
were well-adapted to North Coast conditions, with an emphasis on
lamb and wool production. While this work was successful, it has
limited usefulness in the region today. "Unfortunately, the
local sheep industry is no longer economically viable except on
a small scale," Timm says.
The industry's
decline can be attributed to several factors: increased competition
from Australia and New Zealand (a result of trade globalization),
falling lamb and wool prices, rising production costs and increasing
predation on sheep, particularly on lambs. At the HREC, coyotes
were found to cause about three-quarters of the predator-related
sheep deaths in the 1970s and 1980s. USDA and UC Berkeley researchers
discovered that most of the deaths were caused by dominant breeding
pairs, and scientists at Hopland worked on methods to target these
coyotes selectively (see p. 26 and 32).
The decline
of the North Coast sheep industry contributed to a shift in Hopland's
animal science work. Now, the emphasis includes using sheep and
goats rather than herbicides to control brush. "Natural resource
values have become fully integrated into our agricultural mission,"
Timm says.
Rangeland research
Initial
baseline studies conducted in the 1950s showed that Hopland's natural
forage production was extremely variable. While a sheep could get
enough to eat from just 1 acre during some years, in other years
it took 20 acres to support a single sheep. Hopland researchers
wanted to increase forage production, and one of the center's first
studies showed that seeding pastures with nitrogen-fixing subterranean
clover increased forage production more than fertilizing with nitrogen.
"This
is also cheaper and better for the environment," says UC Berkeley
graduate student Valerie Eviner. "This kind of win–win
situation is rare it's inspiring. And Hopland has provided that
from the beginning."
Eviner is
continuing the Hopland tradition of finding ways to manage soil
problems with plants (see p. 54). While the conventional wisdom
is to focus on one soil problem at a time, she is discovering that
multiple soil problems can be alleviated simultaneously by using
the right combination of plants. For instance, by planting softchess
(a nonaggressive grass) and clover, rangeland managers can both
control erosion and increase nitrogen.
Scientists
are also studying how to control barb goatgrass, an extremely aggressive
introduced species that is invading Northern California and swept
over most of Hopland about 10 years ago (see p. 47). Eradicating
goatgrass is a high priority because the mature plants are not palatable
to wildlife and livestock, unlike some other non-native rangeland
plants.
Watersheds and water quality
Soon after
Hopland was established, researchers began long-term studies of
watershed management at two sites: one that had porous soils (Watershed
I) and one that did not (Watershed II). "Basically, it was
decided that the native vegetative cover would be replaced with
a cover more economical in water use and more productive for livestock,"
wrote Alfred Murphy, Hopland's superintendent from 1951 to 1986,
in a 1976 California Agriculture special issue.
This meant
converting woodlands to grassland. "Back in the fifties, oak
trees on rangelands were regarded as weeds," Timm says. The
researchers cut more than 10,000 oak trees to the ground at one
of the sites and killed them with herbicides at the other. Next
they bulldozed the brush, burned the woody debris, and seeded the
cleared land with forage plants.
While Watershed
I with its porous soils was stable after being converted to grassland,
Watershed II was a different story. Before the conversion, its soil
had also been stable. However, afterward there were 61 landslides
in a decade, and stream sedimentation increased 10-fold (from an
average of 400 to 4,000 tons per year). "We learned that erosion
was highly dependent on the soil type," Timm says.
Now scientists
are using Hopland watersheds to study how to improve rangeland water
quality (see p. 64). After collecting baseline data in seven small
watersheds, they will determine the effects of various treatments,
such as prescribed burning and changes to the grazing regime. One
indicator of water quality will be the number of steelhead trout
that return from the ocean to spawn in Parson's Creek, a tributary
of the Russian River.
Hopland
research is also helping to improve the water quality at nearby
Clear Lake, which gets a small amount of its water from Hopland
watersheds. "Hopland used to relate directly to agriculture.
The greater effort in natural resources management reflects public
sentiment," says Hopland staff research associate Chuck Vaughn,
who has worked there since 1973.
During the
dry years of the 1990s, extensive blue-green algae mats grew in
Clear Lake. These algae mats rose to the surface and rotted in the
fall, smelling so bad in some places that people had to be evacuated.
In collaboration with Hopland staff and using the center's laboratory,
UC Davis scientists found that algae growth was due primarily to
increased phosphorus, much of which came from sediments. The answer
to this algae problem has been managing the lake's watershed,
an effort involving Lake County landowners.
Habitat restoration
In 1993,
Hopland initiated a demonstration riparian restoration project funded
by the California Department of Fish and Game, designed and coordinated
by Bob Keiffer, HREC principal superintendent of agriculture. Some
sections of Parson's Creek were planted with willow, alder, wild
grape and other native species, and selected sections were fenced
to exclude sheep or sheep and deer. The restored riparian vegetation
is becoming well-established there; this has improved the fish-spawning
habitat in Parson's Creek significantly.
Hopland
researchers are also studying oak regeneration in one of the watersheds
that was converted to grassland in the 1950s. "We used to cut
oaks to manage our rangelands, now we're replacing them," Vaughn
says.
In the 40-odd
years since the land was cleared, evergreen oaks have regenerated
on the moist northerly slopes. Deciduous oaks, which favor the drier
southerly slopes, have not regenerated. This suggests that deciduous
oaks will require active restoration, such as planting and seedling
protection, according to Hopland-based researchers Adina Merenlender
and Colin Brooks, of the UC Integrated Hardwood Range Management
Program (IHRMP).
Hopland
is an important site for studying oaks because it "represents
one of the last large, intact oak woodlands in the Coast Range,"
says IHRMP botanist Kerry Heise, who like Brooks and Merenlender
is based at the HREC. Hopland also has among the highest diversity
of oaks in the state.
Led by Merenlender,
Hopland's IHRMP researchers are mapping, monitoring and forecasting
changes to North Coast oak woodlands. They also hold well-attended
UC Cooperative Extension workshops on oak identification, protection
and restoration.
Learning center
Perhaps
most importantly, for a half-century Hopland has been a vital center
of learning that has provided scientific, educational and employment
opportunities for many people. On June 9, 2001, more than 200 of
them gathered at Hopland for a 50th-anniversary celebration. Active
and retired scientists discussed ongoing research and reminisced
about how working at the HREC has influenced their careers and lives.
"The beauty of the landscape, the richness of the resources
and the opportunity to work and learn in an interdisciplinary environment
has made this facility highly productive," Timm says.
"For almost everyone who has worked here, Hopland has become
a special place."
Over the
past 50 years, hundreds of scientists have conducted research
at the station, some of whom lived in residences on site and even
raised families there. Likewise, the center has provided opportunities
for dozens of graduate students, as well as undergraduate interns,
to receive training and field experience. Independent study projects,
and more than 50 master's theses and doctoral dissertations based
on field work conducted at Hopland have not only advanced our scientific
knowledge but also have "aided the growth and maturity of many
promising students from UC Davis, UC Berkeley and other campuses
in ways that are incalculable," Lane says.
Meanwhile,
the small resident support staff has included agricultural technicians,
shepherds, building maintenance workers, mechanics, administrative
assistants and others, some of whom spent their entire careers at
the center. "For every field day, every experiment and every
publication you'll find our group of UC employees working behind
the scenes," Timm says. "It's these men and women, dedicated
to the University's mission at this facility, who make it all happen."
------ Robin Meadows
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