An approach to LM control more consistent with IPM philosophy would be to wait until petal fall and treat with Provado, Spintor or Agri-Mek. Two pre-bloom oil applications provide much better mite suppression than one application. In some years, pear thrips can have a major impact on blossom quality, especially in orchards in the western hills where maple trees are close to orchard borders. Emerging adults can move into orchards in great numbers anywhere from half-inch green through pink. Injured bud tissue at pink is brownish and shriveled.
Bees are reluctant to visit and pollinate thrips-injured blossoms.
So far this year, rather few thrips have been seen even in traditionally vulnerable orchards. But we could still be on the early side of thrips emergence. This week will determine if control will be needed. A tentative threshold is 4-6 thrips per blossom. Even a quarter rate of Guthion or Imidan can provide effective control.