SAN JOSÉ SCALE

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Title: SAN JOSÉ SCALE
Description: LATIN NAME: Quadraspidiotus perniciosus (Comstock) LIFE CYCLE: Overwinter on host as immature scales (black caps). First generation nymphs (crawlers) appear in June; second generation crawlers appear August to September and develop into overwintering scales. Two generations per year. MONITORING: Examine trees during dormant period, fruit at harvest, for scales. Apply double-sided sticky tape around one limb of a tree to monitor for crawlers (smooth bark to improve adhesion). Pheromone is available to monitor for adult males. HOSTS: Fruit trees, ornamental trees and shrubs. COMMENTS: San José scale (SJS) can be distinguished from European fruit scale (EFS) as follows: the tip or nipple of the scale of SJS is central with grooves around it while the tip of EFS is off-center without grooves. The crawlers of both scales are yellow to orange in colour, flattened and slow moving. They resemble apple mealybug crawlers but the latter have red eyes. The presence of antennae distinguish scale crawlers from predaceous mites. BODY LENGTH: Adult - 1.7 mm.