we 



RESULTS ^^ 



New or unusual occurrences . 



Some blocks again experienced a problem with gypsy moths (GM) 

 blowing in during bloom. Very little fruit injury resulted from GM 

 feeding this year, however, and control with petal fall sprays was 

 excellent. Few growers experienced problems with large, late instar 

 larvae migrating from adjacent defoliated oak stands in 1982. 



Spotted tentiform and apple blotch leafminers (STLM/ABLM) were 

 ,.^11 below treatment levels in many IPM blocks where 1981 mine counts 

 had been high. Although some IPM groivers used Vydate* (oxamyl) at 

 pink, others who elected to wait for results of mine counts were 

 able to withhold leafminer treatments for the entire season without 

 the harmful polulation increases that occurred in past years. 



The reasons for this drop in leafminer pressure are unclear, 

 and our present knowledge does not allow us to predict the potential 

 for leafminer problems in 1983. 



Both syrphid fly and cecidomyiid midge aphid predators were 

 abundant in IPM blocks in 1982 (Table 3). In spite of this, honey- 

 dew accumulation was extensive enough to warrant aphicide sprays in 

 10 such blocks. 



Fruit injury . 



Fruit injury at harvest in Previous -year IPM, First-year IPM 

 and check blocks averaged 4.3, 3.8 and 3.5%, respectively (Table 2). 

 The somewhat higher injury level in Previous -year blocks was due 

 largely to sooty mold fungus growing on aphid honeydew observed on 

 21% of sampled fruit in one IPM block. 



This injury resulted from a late season (August) infestation 

 of green aphids on watersprout regrowth in the top center of tree 

 canopies. It is doubtful that such injury is of economic signifi- 

 cance in this case, however, as the grower typically wipes and pol- 

 ishes fruit prior to display in the apple sales room at the farm 

 and should be able to remove most of this injury. 



Of insects causing non-removable injury, San Jose Scale (SJS) 

 was most troublesome and difficult to control in many commercial 

 block samples (Table 2) . For the first time in recent memory av- 

 erage injury from SJS surpassed that of the tarnished plant bug, 

 (TPB) normally the single most injurious apple pest in Massachusetts. 



Lack of adequate SJS control can be attributed to several fac- 

 tors. These include: (a) reduced usage of semidormant oil sprays; 

 (b) frequent and heavy rain showers when treatment was required for 

 1st generation SJS crawlers; (c) grower reliance on concentrate 

 sprays (30-50 gals, per acre) on large trees in hot, dry weather 

 when treating for 2nd generation crawlers; and (d) substantially 

 reduced use of microencapsulated methylparathion (Penncap-M*) in 



n 



Trade Name 



