Eggs are laid under the bud scales, petals and sepals, on stems and in other succulent flower and leaf parts. The larvae feed voraciously for about 3 weeks, adding to the damage already caused by the adults. Sometime in September or October, they pupate in their earthen cell, and remain until the adults emerge the next April. Under natural conditions, the duration of a single adult's life probably covers a period of 4-6 weeks. On fruit trees, feeding is usually concentrated on the tender flower parts, which gives the blossom buds a shriveled, scorched appearance, or may cause them to fall off completely.
Small scars resembling blisters show up along the leaf veins and stems.
The tree will consequently have a thin crown, possibly suffer some moisture stress, and may even drop its leaves prematurely in the fall. Because much of this pest's life is spent underground, control of damaging populations is very difficult. Insecticides have been suggested by some, but their effectiveness is difficult to measure, because most growers are not aware of the damage until after it has already been done, although thrips are sensitive to nearly any prebloom insecticides used in most commercial orchards. This can be a prudent treatment to apply in any case, as a preventive measure against other pests such as mites or pear psylla. Massachusetts guidelines suggest that it can be useful to examine fruit buds at this time to determine whether thrips are present.