where first-generation mines indicated that populations 

 were too low to worry about. Premature drop did not 

 appear to be a problem in any infested block, however. 



Larvae of the apple-and-thorn skeletonizer (An- 

 thophilapariana) were present in one orchard in fairly high 

 numbers, but were completely controlled by an insecticide 

 directed against apple maggot fly in early August. Apple 

 leafminer (Lyonelia speculella) was also found in a few 

 locations this year, but no problems were observed. 



Tarnished Plant Bug . Plant bug captures on white 

 rectangle traps were unusually low throughout the pre- 

 bloora period, not reaching cither the tight cluster or pink 

 threshold in any monitored block. For this reason, some 

 growers were able to withhold insecticides directed against 

 plant bug this year. Plant bug damage at harvest was less 

 than in previous years; of the injury that did appear, much 

 could have been either sawfly (calyx stings) or green 

 fruitworm/oblique-banded leafroUer (large russetted 

 dimples) injury. 



Leafrollers . More oblique-banded Icafroller injury 

 was seen than is usual this year in monitored, first- and 

 second-stage IPM blocks, but still did not appear to be at 

 a level of concern. Early-season leafroller damage was 

 found in some blocks, especially low-spray blocks; this type 

 of injury is unusual in Massachusetts. Apparently the small 

 window of sawfly/curculio activity and control gave the 

 leafrollers a chance to move in after petal fall. Pesticide 

 resistance on the part of oblique-banded leafroller is also 

 a possibility, although damage was more notable in lightly- 

 sprayed blocks than in heavily-sprayed blocks. Overall 

 leafroller injury remained very low, however, amounting to 

 less than 0.2% of surveyed fruit. 



A pple Maggot Fly . Overall maggot fly pressure was 

 low, and very little damage was found. There did not 

 appear to be a late-season flush of apple maggot fly 

 activity, as there has been for the last few years. 



Aphids . Aphids were eventually controlled by preda- 

 tors, but populations tended to hang on longer than usual, 

 especially on water sprouts, where they could be found 

 until mid-July in some blocks. This delayed effect could 

 have been due to the presence of spiraea aphids in addition 

 to green apple aphids, or to some other factor. No 

 honeydew problems were seen in any monitored block. As 

 in 1987, cecidomyiid midge larvae were the predominant 

 predator, ably assisted by syrphid fly and camaemyiid fly 

 larvae, minute pirate bugs, ambush bugs, and ladybird 

 beetles. 



Ladybird Beetles . Populations of ladybird beetles 

 were noticeably higher statewide this year than in previous 

 years. 



Mites /Predators . Mite activity appeared to level off in 



late summer; some growers who had originally planned to 

 treat decided to wait, and ultimately did not need a miticide 

 at all, or were able to use a low rate or spot treatment. 

 Once again, dormant oil appeared to be a highly effective 

 method of preventing mite buildup. Miticide use averaged 

 close to 1 DE in 9 commercial blocks, down from the usual 

 average of 2 DE of miticide (not including dormant oil). 

 Summer oil at 1 quart/ 100 gallons was used successfully in 

 one monitored block, with no apparent ill effect on fruit or 

 foliage. Predators continue to build in commercial or- 

 cha.r(is\Amblyseius fallacis and Zetzellia mali built up later 

 than usual, and were lower in number than in 1987, but 

 were still of value in several blocks. Rain in late summer 

 probably also helped wash mites off leaves. 



Lcafhoppers . Potato leafhopper was not much in 

 evidence this year, except in one low-spray block of young 

 trees, where it disappeared entirely after an organo- 

 phosphate insecticide was applied. White apple leafhop- 

 per was at a problem level in one first-stage and a few 

 second-stage IPM blocks, but overall it did not present a 

 major problem this year. 



Catfacing Insects . Activity was very low to moderate 

 in peach blocks this year. Many growers reduced insecti- 

 cide use with no noticeable ill effects. 



Earwigs . Several instances of earwig injury to apples 

 in commercial orchards occurred, especially on Cortland 

 fruit. Injury was most often in the stem end and took the 

 form of chewing as well as substantial frass accumulation. 

 It was not possible to tell whether the earwigs had initiated 

 the injury or only moved in later and enlarged previous 

 wounds. 



Scab . There were only 5 or 6 (depending on location) 

 actual scab infection periods, though the length of these 

 generally exceeded 36 hours. Frequent wetting periods, 

 which were not Mill's periods, occurred during primary 

 season. The timing of sprays was difficult due to the length 

 of the wetting periods, and windy weather. Growers who 

 missed a spray, or even missed a few trees, had some 

 trouble for the rest of the season which would have been 

 worse except for the dry summer weather. The average 

 fruit scab injury for IPM monitoring blocks was generally 

 low (0.47%) except for one block where mechanical break- 

 downs interfered with the scab spray schedule, and injury 

 was 5.5%. 



Sooty Blotch and Flvspeck . These problems were 

 evident in a number of blocks, especially on Golden Deli- 

 cious apples. 



Calyx End Rot. Black Rot, etc. Very little of any of 

 these problems were noted in monitored blocks, especially 

 when compared to the levels reported in previous years. 

 There were some instances of Botrytis-mAaceA end rot 



17 



