July 3, 2004
Vineyard berms seem little more than narrow barren strips of soil beneath the vines. However, growers will tell you it is one of the most nettlesome areas in producing wine grapes.
Let weeds gain control of that ribbon of bare dirt and those berms become breeding grounds for pests with those same weeds acting like a steel curtain to block pest management control measures.
Left uncontrolled, weeds like marestail can snake up into the vines, damaging fruit.
“Weedy berms not only rob vines of nutrients and water, they also can be pest hotels. Weeds on the berms can suck the vitality out of a vineyard,” said Preston Watwood, vineyard manager of 800 acres of General Vineyards Services (GVS) vineyards in the Salinas Valley near Gonzales, Calif.
Kelly McFarland, president of GVS, says Monterey County is a perfect year-round environment for weeds.
“We can have any weed any day of the year,” said McFarland. It is warm in the winter and mild in the summer.
“I have found London Rocket in the summer here. Where I grew up farming in the San Joaquin Valley, London Rocket is a winter weed,” said McFarland, whose family farms 3,000 acres of wine grapes in Monterey County.
GVS vineyards are broken up into 14 ranches in four different locations in the valley. The company sells wine grapes to about 25 wineries each year.
‘Expenses keep going up’
Eighty percent of GVS' berm weed control is now chemical, but McFarland wants to switch to more mechanical weed control.