1.50 



1.00 



3 



se °- 50 



0.00 



OTHER 



Figure 2. Harvest injury in first-stage IPM blocks. Insect injury 

 in 1978-88 as compared to injury in 1989. TPB = tarnished plant 

 bug; EA = European apple sawfly; PC = plum curculio; LR = 

 leafrollers; AMF = apple maggot fly; GFW = green fruitworm; 

 CM = codling moth; SJS = San Jose scale. 



Mites . Again this year, mite populations were 

 generally low, although there were some notable ex- 

 ceptions, and growers in the monitoring program used 

 an average of 1.25 dosage equivalents of miticide. 

 Predators continued to increase in many of the state's 

 orchards, including Amblyseius fallacis, Zetzellia mali, 

 Orius insidiosus, and also possibly Stethoruspunctum. 

 Predation was late building up this year. 



Plum curculio . Curculio activity was unusually 

 prolonged (through early July in some orchards) but 

 the level of harvest injury in most first-stage blocks was 

 not unduly high, perhaps because growers were alert 

 and treated promptly. Some blocks, however, did have 

 unusually high levels of late-June curculio injury. 



White apple leafhopper . This insect is increasingly 

 evident in Massachusetts orchards, and may be associ- 



ated with the fire blight outbreak 

 mentioned above. 



Green fruitworm . Damage that 

 appears to have been caused by green 

 fruitworm has been showing up in our 

 harvest surveys (0.6% in one 12-block 

 survey), although it does not seem to 

 be of concern to most growers, and 

 injury levels probably do not justify a 

 special application of insecticide. 



Leafroller/slug . A fair amount of 

 surface feeding was noted at harvest in 

 some blocks, although much of this 

 feedingwas on dropped fruit. Some of 

 it was caused by leafroller, but slugs 

 also had a field day with the damp 

 weather, and have been seen on at- 

 tached fruit as well as drops. 



Aphids . In most orchards, aphids 

 seemed to come and go very quickly 

 this year. Predators were abundant. 

 Some growers used Thiodan T M against the summer 

 flight of leafminers, which would have contributed to 

 the early demise of the aphids; also, the cool.wet 

 weather may not have allowed aphids to flourish at 

 their usual levels this year. 



Tent caterpillars/gypsy moths . These caterpillars 

 were more common this year than they have been for 

 a while. Apparently another population outbreak is 

 predicted in the next few years. Neither insect pre- 

 sented much of a problem to growers except on non- 

 bearing young trees that were not under a full spray 

 program. 



Thrips . Numbers of pear thrips were substantially 

 lower in commercial blocks than they have been in 

 recent years, although they still caused some reduction 

 in fruit set in low-spray, non-commercial orchards. 



4.T.* *% C% «f« fcf> 



«rj% cy» e|^ #{% r£» 



Fruit Notes, Winter, 1990 



29 



