Kern County growers are likely to be pleased with their 2010 pistachio crop, says Craig Kallsen, the county’s UC Cooperative Extension Farm Advisor.

“Things look good to me —I haven’t been getting many calls from growers, which is a good sign they’re having few problems.”

Fungicide treatments in response to an unusually wet, cool spring prevented diseases like Alternaria, Botrytis and Botryosphaeria, from gaining much of a foothold. But, he says, there’s still the possibility of an outbreak of Alternaria or Botryosphaeria this month.

The biggest threat still facing the crop’s No. 1 pest problem — navel orangeworm. “I’m sure a lot of PCAs are in the orchards at this very critical time when the nuts are starting to split,” Kallsen says. “The moths like to lay eggs next to splits in the hull. Early splits usually start showing up in late July.”

Some observers are projecting that California’s 2010 pistachio production will total the same or higher than last year. But, yields from Kallsen’s West Side tests plot this season (an off-year for alternate bearing pistachios) appear to lighter than in 2009. He expects trees in his plots on the east side of the county along Highway 65, where this is on-year for pistachios, to produce a bigger crop than in 2009.

“They are really on this year,” he says. “The wild card is the added production from some of the younger trees that are just now coming into bearing. They should make up for yield deficiencies of any off-year trees.”

Many of the younger trees were planted in the past five to eight years on former cotton ground. Pistachios are similar to cotton in salt tolerance. Some of these new trees, Kallsen says, are early-maturing varieties Golden Hills and Lost Hills, developed by UC breeders and released five years ago.

“These two varieties were planted on a significant number of acres,” he says. “We won’t begin seeing their initial impact on production for another year or two.

“We’ve had very good summer weather for pistachios — dry with some favorable high-90 and 100-degree days.”

With the unusually mild weather, he anticipates the Kerman harvest will begin about a week later than the more typical Labor Day start. Shaking of early varieties could get under way in late August.