Navel Orangeworm: a Pest of Pistachio Nuts in California

The navel orangeworm, Amyelois transitella (Walker), has become the primary insect pest of pistachio nuts, Pistacia vera L., in the San Joaquin Valley of California. Damage to pistachio nut meats is similar to that caused by navel orangeworm to almonds and walnuts, but it is more difficult to detect during processing operations prior to marketing. Experimental insecticides applied to nuts during the early hullsplit period reduced larval infestations by 55–78%. Control of navel orangeworm in pistachios appears feasible by combining orchard sanitation, preharvest insecticide sprays, and early harvest into a seasonal pest management program similar to that practiced in almonds.