San Jose Scale is the most prominent scale insect found in apples. San Jose scales infest branches, shoots, leaves, and fruit. The scales suck plant juices from the trees and inject a toxin. Infested fruit tends to be bumpy, and in the extreme, severely misshaped and stunted. San Jose scale can seriously weaken branches and main scaffold limbs and kill fruiting spurs, thus causing permanent injury and even death to mature trees. The best time to apply a fruit tree spray
is in the early spring If by this time, there has been no rain, irrigate your orchard. Oil sprays can be phytotoxic to water-stress trees. Before a dormant spray is applied, irrigate your orchard using two- to three- acre inches of water. This will allow you to wet the soil profile 24 to 36 inches. This water is not wasted water since root growth and development starts. Furthermore, if the water that is not used by the roots, it will be stored in the soil profile for use in the early spring.