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Issue date: Nov-Dec 2001
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Progress report
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 Scientists are conducting grape trials at Hopland to test irrigation protocols and the suitability of varieties to North Coast growing conditions. Photo by Phil Schermeister |
IN his quest to bring new varieties
to California's wine industry, Glenn McGourty has taken on a project
other agricultural researchers could only dream of: He's sampled
imported wines, toured southern Europe, grown prized grape cultivars
and savored the results of his experiment.
McGourty,
a viticulture and plant science advisor for Lake and Mendocino counties,
is testing 19 European cultivars at the UC Hopland Research and
Extension Center (HREC) to help grape growers select those that
are suited to California. He chose Hopland because its climate (Winkler
Region III) is similar to that of many wine-producing regions in
the state: Lake County, Ukiah, Calistoga and Paso Robles.
"Acreage
has increased all over the North Coast," McGourty says, "and
I wanted to look at new varieties for California." He added
that many of the big-name cultivars, such as Char-donnay, Pinot
Noir and Merlot, originate in northern France, which is colder than
California. If California wants to produce truly great wines, he
notes, the state's vintners need to consider varieties that grow
in similar climates. "If you find plants from climates that
are similar to yours, you can expect a good result."
McGourty's
research began in 1991 when a restaurateur friend, Giovanni Leoni,
started sharing his knowledge of fine wines. Leoni introduced McGourty
to wines from Italy, France and Spain regions with mild winters
and warm, dry summers like California's.
McGourty
noted his favorites and obtained scion wood, or the part of the
plant that's grafted onto the rootstock, from nurseries, growers,
the UC Foundation Plant Material Services and the U.S. Department
of Agriculture's Wine Grape Germplasm Repository. Nurseries, growers
and equipment suppliers donated much of the stock.
On a 2-acre
plot near the Russian River, McGourty grafted onto 5C rootstock
60 plants of each cultivar, enough to produce a barrel of wine,
or 20 cases, for each variety. The site stands at 550 feet elevation
and has a 2% slope. After McGourty planted the vines in 1994, he
had local and European ampelographers, or grapevine-identifying
specialists, verify the correct identities of the cultivars. There
were a few surprises: The Roussanne cultivar was really Viognier,
and the cultivar Melon was mixed in the with Arneis.
While the
vines reached maturity, McGourty toured Europe along the Mediterranean
coast, learning how Portuguese, Spanish, French, Italian and Greek
winemakers plant, prune and train the varieties. He brought this
knowledge back to his own plot at Hopland and is treating his plants
the same way, irrigating the vines just enough, pruning to encourage
strong growth and thinning to yield a moderate crop load. He also
protects the vines from frost with overhead sprinklers and netting
to keep out birds.
Every year
McGourty notes when the vines break buds and flower and when the
grapes change color and are harvested. He measures the size of the
berries and clusters, the yield and the percent of sugar and the
pH of the grapes. In 2000, the first full year of harvest from his
experiment, he picked the grapes when the sugar content was near
23.5° brix. He then convinced a few local vintners to turn
some of the grapes into wine. The results, he says, were "excellent."
The research
continues, but preliminary results point to a few exceptional varieties:
Montepulciano, Fiano and Corvina. McGourty notes, however, that
wine quality changes from year to year, so other varieties may shine
in the future.
As a result
of McGourty's research, Material Services has added some varieties,
including Tempranillo, Fiano and Aglianico, to its collection. And
the research continues: McGourty hopes to plant additional cultivars,
including six that were grown in vineyards near Pompeii during the
time of the Roman Empire. At another site, he's experimenting with
Syrah clones.
Unfortunately,
most of us won't be able to taste any of these varieties soon. Grape
growers need 5 to 6 years for the vines to mature, then must convince
a winemaker to bottle the results. "It takes a long time to
start a new trend in wine," McGourty says.
----- Mandy Erickson
Genetic variation data could help blue oak reseeding efforts
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 In a "common garden" plot at the HREC, scientists are studying genetic variation among trees grown from blue oak acorns collected at 26 California locations in 1990. Photo by Jack Kelly Clark |
THE rapid conversion of blue
oak woodlands to savannah and grassland, coupled with suburban development,
has resulted in significant declines in blue oak habitat, with an
estimated 591,000 acres destroyed between 1945 and 1980.
"As
we attempt to restore habitat and reseed blue oak statewide, scientists
are concerned about a possible loss of genetic diversity in this
native species," says UC Berkeley forestry professor Joe McBride.
"Loss of genetic diversity poses long-term consequences for
the maintenance of the species throughout its natural range."
McBride
is studying genetic variation of blue oak in a "common garden"
experiment at the UC Hopland Research and Extension Center (HREC)
in southern Mendocino County.
A beautiful
and notoriously slow-growing tree, blue oak (Quercus douglasii)
reaches heights of 20 to 60 feet tall and is long-lived, typically
surviving 175 to 450 years. It grows at elevations of 500 to 2,000
feet in the north of California and up to 5,000 feet in the south.
The tree generally occurs on hot, dry slopes that surround the Central
Valley.
The common
garden method is based on the premise that when seeds are collected
from a wide range of environments and grown under uniform conditions,
genetic variability will be expressed in the plants, cuttings and
seeds collected.
In order
to establish a common garden of blue oaks at HREC, McBride collected
seeds from 26 locations in 1990, from sites about 50 miles apart
in the Sierra Nevada foothills and Coast Range. At each site, about
150 to 200 acorns were collected from each of 10 trees. The research
is partially funded by the UC Integrated Hardwood Range Management
Program.
The seedlings
were sown at a California Department of Forestry and Fire Protection
nursery in Magalia, Calif., in 1991 and planted in 10 major blocks
at Hopland in 1992.
Eight years
into the experiment, McBride has found some trends in blue oak genetic
variation, expressed in differences in shoot growth, phenology (timing
of growth) and mineral accumulation.
An analysis
of plant diameters and growth did not reveal consistent trends in
relation to elevation or latitude. But there has been an increasing
trend in dormant plants among higher-elevation trees. "This
suggests that dormancy may be temperature-related," McBride
says.
Leaf tissue
analyses have also shown greater accumulations of nitrogen, phosphorus
and sulfur among high-elevation trees. "We hypothesize that
the shorter growing seasons and trend toward less nutrient-rich
soils, may have been selective forces for a greater capacity to
absorb minerals at higher elevations," McBride says.
Nonetheless,
few of the plant characteristics measured so far have been statistically
definitive for delineating a geographic pattern of genetic variation
in blue oak, warns McBride, who will follow the trees over the next
10 years to determine if firm trends can be identified.
The results
could have critical implications for the long-term survival of this
unique California tree, McBride says. "Understanding the degree
and geographical pattern of genetic variation in blue oak is essential
in evaluating the significance of the loss of local populations,
and could serve as the basis for developing seed-acquisition rules
and gene conservation strategies."
-----Janet Byron
Suburbia aside, black-tailed deer are in decline
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 Although suburbanites may disagree, there is agreement among scientists that black-tailed deer populations have been declining in California since the mid-20th century. Photo by Guy E. Connolly |
SUBurban gardeners waging a
ceaseless battle to protect their roses and fig trees from hungry
deer may scoff at the notion, but California's black-tailed deer
appear to be on the decline.
Scientists
have noticed fewer deer around the UC Hopland Research and Extension
Center (HREC), and while their counts aren't definitive, they believe
the deer population has been waning through the last half of the
20th century.
By their
best estimates, HREC's resident deer numbered about 600 adult animals
during the 1960s, but only half that many were present by the early
1990s. California Department of Fish and Game (DFG) deer kill records
for Sonoma and Mendo-cino counties during this period show a parallel
decline; former HREC wildlife biologist William Longhurst and his
colleagues first noted this trend beginning about 1969.
"It's
kind of a no-brainer based on people's personal observations,"
says Karen Kovacs, DFG senior wildlife biologist in Eureka. "Black-tailed
deer are getting harder to find."
While the
decline is obvious to deer hunters and scientists who observe deer
in rural areas, it's not as apparent to suburbanites. "The
behavior of deer in California has changed dramatically to enable
them to live in human neighborhoods," says Dale McCullough,
UC Berkeley wildlife professor. In higher density suburban areas
like the Bay Area, deer can damage landscaping and cause traffic
hazards; they are also beginning to draw predators such as mountain
lions.
Despite increases
near towns and cities, the deer population decline in other areas
appears to be real. Less obvious, however, are the causes for this
decline. Scientists at HREC have been conducting studies since the
1950s on what HREC Superintendent Robert Timm calls "the best-studied
herd of black-tailed deer anywhere." Their research may offer
some clues.
Climate change.
Unfortunately, the effects of weather are too complicated and subtle
for researchers to draw definitive conclusions. However, climate
research is currently thriving because of concern over global warming.
McCullough, who recently completed a 19-year deer productivity study
at HREC, notes that Pacific climatic patterns spanning decades are
now known to re-occur, and tree-ring growth data from Lake County
appear to confirm a decrease in woody plant productivity over the
same period. McCullough speculates that climatic change could affect
deer directly through their food supplies, or indirectly by affecting
their parasites or predators.
Predation
and hunting. In recent years, the HREC has apparently lost more
sheep to coyotes, and scientists speculate that deer also may have
suffered increasing numbers of kills. While the scientists haven't
been able to count deer kills as they have with sheep, they have
noticed that lamb losses to coyotes decrease in June when newborn
fawns are available and relatively vulnerable. Also, mountain lions
began to attack sheep at HREC starting in 1985, demonstrating that
the big cats whose favorite meal is venison have returned to the
area.
Human predation
on deer has also been considered as a factor. However, carefully
regulated hunting at HREC, including deer removed for research purposes,
removes only a small portion of the population. Several HREC studies
have shown that the deer regain their numbers through increased
fawn production.
Overpopulation.
A more traditional explanation may be earlier overpopulation. By
the early 19th century, Europeans who moved to California had begun
to modify the landscape in ways that improved deer habitat. These
settlers shot the native mountain lions, and fewer deer became prey.
They logged trees, and the new forest growth provided forage for
deer. And they opened land for pasture, which deer as well as livestock
grazed.
By the 1920s,
game laws and hunting seasons were in place to limit hunter harvest
of deer. By the 1940s, California's deer population had peaked,
according to Longhurst and his colleagues. Soon after that time,
logging slowed, land dedicated to grazing decreased and, in the
1970s, mountain lions became a protected species.
In short,
the numbers of deer at HREC in the 1950s and early 1960s may have
been greater than the range could support in the long run. "Deer
have the ability to literally eat themselves out of house and home
and in effect are truly their own worse enemies," Longhurst
says.
Changing
land use. Statewide, perhaps the most important reason for deer
decline is the degradation and fragmentation of its habitat in recent
decades. Timber harvest has slowed, and livestock numbers and the
amount of land dedicated to grazing have decreased. Wildfires have
been aggressively controlled. Growers have fenced off agricultural
lands to prevent deer damage, and housing developments have taken
over land that deer once grazed. While gardens offer some forage,
drivers hit and kill deer, poachers shoot them and many landowners
fence their property. For most wildlife biologists, habitat change
is among the obvious causes of deer decline.
"We're
consuming habitat at an alarming rate," says Kovacs, "and
something's got to give."
-----Mandy Erickson
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