Yolo wineries not worried about storms
By ALDRICH TAN/Democrat Correspondent

January 9, 2006

Some of the county' grapevines, such as those at the R.H. Phillips Winery in Esparto, briefly spent some time underwater during last week' heavy rains.

Winter storms in Yolo County caused water from Oak Creek, a seasonal creek next to R.H. Phillips, to go over the banks, said Rod Scheaffer, director of vineyard operations.

"You can still see wood and debris (left by the creek) out on the county road," he said.

But county wineries are not panicking about their precious plants because the grape harvest is over and the plants are dormant, said James Wolpert, department chairman of the Viticulture and Enology department at UC Davis.

"It is a commodity that has been able to literally and figuratively weather a severe storm that flooded many people' homes," he said.

During the winter, grapevines lose their leaves and go into a plant version of hibernation, Wolpert said. The plants evolved this tactic to survive temperate origins where winter temperatures can drop below zero.

"These hibernating plants won't have the sensitivity that a plant that is still green and needs to stay active," he said. "They can survive underwater for weeks."

Another key reason why Yolo County didn't experience much agricultural flood damage is because of its land formation, county agricultural commissioner Rick Landon said.

"Our lands just didn't flood," he said. "There was a lot of water running down the bypass and down the Sacramento River, but there wasn't potential for severe flooding. Our flood control systems worked fairly well."

The county' vineyards are largely located in three specific appellation areas, areas designated by local wine associations that are unique for certain weather and soil conditions, Landon said. Those areas are Dunnigan Hills, where R.H. Phillips is, Clarksburg and Capay Valley.

"Dunnigan Hills is an area not threatened by flood," Landon said. "On the other hand, Clarksburg is close to the city of Sacramento and there is a threat of flood only if the levees break."

Wineries also take extra precautions to prepare for the annual winter storms by stabilizing the soil, Scheaffer said. Stabilizing the soil protects the grapevines from erosion, which can potentially cut down the plants to a point where the roots would be exposed.

"It would end up being difficult to go in a middle of a grapevine row to repair that kind of thing," he said. "Erosion could also prevent winery workers from doing their fieldwork and delay necessary tasks such as pruning and chopping brushes."

For the last couple of years, R.H. Phillips delays weed spraying until later in the season since the weeds provide a solid ground cover for the vines, Scheaffer said

"We also used hay bales to control the erosion and it helped retain the cover crops," "By letting the grasses grow, you're stabilizing the soil," he said.

Scheaffer said the winery also uses an aerator, a machine that punches holes in the soil. The holes allow the water to penetrate into the soil so that there is less runoff that could increase localized flood potential.

Localized flooding damaged small parts of various alfalfa and some wheat crops, Landon said. Areas where wheat and alfalfa damage occurred include Esparto and Cache Creek. The Lamb Valley Slough is one area that did flood.

"But most of the water is now off those plants," he said.

There is a little standing water left at the R.H. Phillips vineyards, Scheaffer said. The vines will go through another month of pruning. In March, the grapes will start to grow and then they will continue to bloom through late August. This year' wine harvest takes place in September and October.

"We're expecting that there is going to be normal rainfall so nothing as extreme as over the weekend," Scheaffer said. "The timing of the storm over the New Year weekend meant that wine production is pretty slow. If it was going to rain really hard, I'm glad that it happened that weekend."