Use the thresholdslisted above to determine if a treatment is necessary. On very susceptible varieties, such asSan Joaquin Valley navel oranges, monitor fruit at least twice a week after petal fall. Lesssusceptible varieties such as Valencia oranges may not require treatment. Optimal timingof these contact materials is usually shortly after petal fall, but can be delayed depending onweather and on thrips development. Legs are also a whitish color.
Adult females insert eggs into the leaf or fruit surface.
Just before hatching, egg blisters,which denote where the eggs are, develop and can be seen with a hand lens. These globules of fluid increase in size until they fall off andanother one begins to form, resulting in a characteristic spotting of the infestation area withblack specks of fecal material. The prepupa and pupa are also whitish to slightly yellow. Neither pupal stage feeds, butremains among the feeding congregation of thrips. All stages of this thrips are sluggish andthe adults rarely fly.