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Birds can devastate wine grape crop

POLK COUNTY -- The 100 acres of grapes at Scharf Bros. Farm near Perrydale should be ready for harvest in about a week or two.

Justin Scharf sets up a timed propane cannon at Scharf Bros. Farm near Perrydale Thursday. The device is designed to control birds on wine grapes.

Photo by Pete Strong

Justin Scharf sets up a timed propane cannon at Scharf Bros. Farm near Perrydale Thursday. The device is designed to control birds on wine grapes.

October 03, 2012

POLK COUNTY -- The 100 acres of grapes at Scharf Bros. Farm near Perrydale should be ready for harvest in about a week or two.

Co-owner Justin Scharf said this season should be a good one. With luck, the vast majority of the pinot noir and pinot gris he grows should be off the vines before "they" come.

"They" are migratory birds ... with hearty appetites.

"There are small groups showing up right now," Scharf said on a recent day as he rigged the timer on a propane cannon, one line of defense against the birds. "But nothing like those big flocks.

"When it gets bad, they start to look more like swarms than flocks."

Vineyards are on track for a normal start to picking in 2012, a change from the cool springs and summers of the last two years. Still, though robins, jays and particularly pesky starlings don't usually arrive en masse until later in the fall, vintners and growers aren't letting their guards down.

They'll start rolling out a variety of control measures to keep birds at bay, including netting, devices that pump out predator sounds through speakers, and visual deterrents such as beach-ball sized vinyl balloons and reflective tape. Workers rolling through trestles on four wheelers will also become more prevalent.

"Once it starts freezing in the north, that will drive those migrating birds down and we'll get that pressure," said Luke McCollom, vineyard manager for Left Coast Cellars. He added that birds can get wise to controls, however, "so we try to start those controls as late as possible."

Birds are opportunistic and can inflict major damage to grape clusters. If one vineyard has managed to chase them away, they'll move to another vineyard and become somebody else's problem.

Scharf said you can spend anywhere from $2,000 just keeping birds away to $10,000 in a bad year. In 2011, his vineyard still had grapes on the vine in early November and the birds were ready.

"It wasn't that big of an area, but we still had three guys out there all days on four-wheelers with shotguns," Scharf said. "But they were persistent, it's like they're in a frenzied state when the grapes are that late."

The damage?

"We went from having close to 40 tons in that block to 10 tons," Scharf said.

The more measures you employ, the better. But not all are easy to use. The Scharfs tried agricultural pyrotechnic devices that are shot from pistols and screech across a vineyard or pop after being launched like bottle rockets.

"They work," Scharf said. "But during the last two years, the Bureau of Alcohol, Tobacco and Firearms has made storage regulations for (explosive devices) so much more intense that we gave up on trying to meet those rules."