| Low temperatures
may distress crops

Canoe Ridge Vineyard, January 2004 |
This story was published Jan. 7, 2004
By Anna King
Wine Press Northwest
Scientists, growers and winemakers won't know until they prune their
vines early next month to what degree this week's sub-zero temperatures
have damaged the 2004 crop of Mid-Columbia wine grapes.
The frigid temperatures remind many in the industry of 1996, when
cold devastated about 40 percent of Washington's wine grape crop. The
industry is valued at about $2.4 billion.
"There is not much you can do about it," said Scott Williams,
wine maker and vineyard manager at Kiona Vineyards near Benton City. "From
a grape grower point of view, you should be worried."

Kiona Winemaker Scott Williams |
At Kiona, Sunday night's temperature plummeted to about minus 13 degrees,
Williams said. He said it's too early to determine how much damage
has occurred, but he estimated some buds, where the plant will grow
this spring, probably were damaged. Fields closer to the region's rivers
were expected to fare better because of generally warmer temperatures.
Those hardest hit are expected to be at lower elevations, such as valleys
away from the water.
However, some scientists say many vineyard owners have adopted new
growing techniques since the last big freeze and might be a little
better off.
Not everybody was as optimistic.
"I think it could be a lot like '96," said Sara Spayd, a
Washington State University extension food scientist based in Prosser. "The
major difference is that we haven't had a lot of sunlight, which was
one of the problems in 1996."
That year sunlight warmed the trunks of vines quickly during the day
from the reflective snow, but at night temperatures would plummet,
Spayd said. The grape vines couldn't handle the extreme differences
in temperature, she said.
This week's weather has been more cloudy, keeping the vines at a more
constant, cold temperature.
In 1996, the cold snap followed warm weather, so vines weren't as
dormant and prepared for the cold, Spayd said. This year, the cold
set in more gradually.
Spayd said such extreme cold snaps strike every five to six years.
"We try and prepare new growers that every five to seven years
you are going to loose a crop," she said. "And this is year
eight."

Bud Break will show how Washington's
Vines Survived the Cold Winter |
The industry has grown dramatically in that time.
In 1996 the state had about 13,000 acres of wine grapes, said Stacie
Jacob, spokeswoman
for the Washington Wine Commission. This year that figure grew to about
28,000 acres, with nearly 99 percent of those grown in Eastern Washington,
she said.
Jack Watson, a WSU extension horticulturist,
said certain varieties are less hardy than others. He said tender
varieties include grenache,
syrah, merlot and sangiovese. Some of the more hardy varieties include
riesling and gewürztraminer.
Ironically, some of the most tender varieties are the most popular
and valuable, Watson said.
Location also is an important factor. Cold air sinks and follows land
elevations, so valleys become much colder. Watson said growers who
plant more hardy varieties where cold air settles or use wind machines
to raise the temperatures might experience less damage.
Because of the vastness of many Eastern Washington vineyards, many
growers find the protective practice of burying their vines or wrapping
them in plastic too costly, Watson said.
In February, when growers prune, they may decide to leave more buds
on the vines to make up for those that might have been killed, Watson
said. But it still is too early to say how extensive the damage will
be, he added.
Despite the expected hardship, Washington remains one of the best
places to grow wine grapes, Kiona's Williams said.
"It's not going to be a banner year, but you never can tell," he
said.
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