The wings are lighter, especially at their bases. The eyes are dark reddish brown. The larvae are white and possess a ring of dark spines on the underside toward the posterior end. Adult western flower thrips range from clear lemon yellow to yellow brown to dark brown in color. This causes the buds to dry and die or to develop abnormally.
Damaged buds produce droplets of gum, which help pinpoint a pear thrips infestation.
Western flower thrips may damage pears grown in northern California, but it is more of a problem for pears grown in southern California districts because it migrates into the orchards from nearby deserts. Each puncture results in a slightly depressed russetted spot, between 0.125 and 0.25 inch in diameter. Tap clusters on the palm of your hand to dislodge adult pear thrips. Damage thresholds have not been established for treatment. If several thrips, on the average, can be dislodged onto a sheet of paper by tapping individual flower clusters, a treatment may be needed to prevent damage.