Entomologist Walt Bentley found some spider mites on leaves at the base of an almond tree.
For Butte and Padre, he recommends more of a focus on disease management and less on insect pressure.
With Monterey and Fritz, Bentley said, there are more management pressures, and it may be necessary to do two or three sprays depending on when harvesting can take place.
Bentley said growers also need to take into account if there is a neighboring susceptible block. He pointed out that the navel orangeworm is able to overwinter at greater percentages at points further south in California.
One grower supplied a baggie containing green soldier stink bugs that had dropped to the orchard after application of a pesticide.
That pest is more likely to over-winter in an orchard, Bentley said.
He said that both insect pests leave a distinctive “thin curlicue, like a little pig tail” on the surface of the nut.
The stink bug leaves eggs that are “barrel shaped clusters,” which Fresno County grower Andrew Vargas said he found in his orchard on the county’s west side. Bentley said they may resemble a long, thin necklace “like macaroni strung together.”
“If you’re seeing them, treat,” Bentley said. “They’re not that easy to find.”
One way to detect that insect — or perhaps the leaf footed plant bug — is to rap the limb of the tree and get the insects to drop or fly off.
“You need to focus your eye on a smaller world,” said Bentley, who fishes as a pastime. “It’s like a hunter watching for a silhouette or a fish in the water.”
Bentley said Lorsban can be used to control both pests, but he advises against using that unless the orchard is “isolated from water” due to concern over contamination of groundwater.
“If I were in Mendota, there’s no way I would touch that material,” he said. Among alternatives he recommended is Bifentrin (Brigade).