Last fall was dry and warm, winter turned cold, and spring has been wet and now unseasonably warm.
What does that tell about possible pest issues this season?
“It’s nearly impossible to predict how winter weather will impact pests during 2007, especially mites,” says David Haviland, Kern County Farm Advisor. “As far as growers are concerned, the upcoming season should be dealt with the same as for any other season — learn mite species, monitor for them, and base treatments on established thresholds.
”I haven't spoken to many grape growers about mites this spring, but many almond and stone fruit growers at the lower end of the San Joaquin Valley were already finding adult female mites and lots of eggs in trees about the second week of March.
“Hopefully, this is just a result of uncommonly warm March weather. But it could also be an indication that mites will be something to watch out for during 2007. Only time will tell!”
The glassy-winged sharpshooter (GWSS) situation is also difficult to ascertain at this early point in the season.
“GWSS might be reduced due to the cold weather in some parts of the Central Valley, but there is conflicting information at this point,” says Corky Roche, Roche Vineyard Consulting at Salinas. “Chilling may help the overall crop level.
“That’s not necessarily good for the industry, considering the oversupply of grapes, but it’s good for individual growers, especially in areas where sufficient chilling hours are sometimes less than optimal.”