Apple IPM Program: 



Delivery and Observations in 1988 



Kathleen P. Leahy, Ronald J. Prokopy, Susan A. Johnson, and William M. Coli 

 Department of Entomology, University of Massachusetts 



Daniel R. Cooley 



Department of Plant Pathology, University of Massachusetts 



James T. Williams 



University of Massachusetts Cooperative Extension, Concord, MA 



Our thanks to the following cooperating growers in 

 the IPM monitoring program this year: Charlie and Alex 

 Dowse, Ed Jensen, Tony Lincoln, Tony Rossi, Don Sch- 

 licke, Steve Smedberg, Mike and Tim Smith, Mike Smo- 

 lak, and Denis Wagner. Special thanks to Sue Butkewich 

 for technical assistance. 



Ovendew of the Program 



The 1988 Massachusetts Apple Integrated Pest Man- 

 agement (IPM) Program was a mixture of "old" and new 

 approaches to orchard pest management. As always, we 

 monitored commercial blocks for insect and disease activ- 

 ity and reported the information to the state's growers, via 

 newsletters, recorded Code-A-Phone messages, and di- 

 rect grower access of INFO^fET, our computerized bulle- 

 tin board system. Some pesticide trials and other related 

 research was conducted at the University of Massachusetts 

 Horticultural Research Center, Belchertown. In addition 

 to these activities, however, we are now working toward 

 melding our more-proven, first-stage-IPM pesticide-re- 

 duction practices with some of the more-radical practices 

 involved in second-stage IPM into a unified "third stage" 

 of greatly reduced pesticide use without loss of crop quality 

 or profitability. 



Monitored blocks (7 out of 9 blocks reporting pesti- 

 cide records) received an average of 4.3 dosage equivalents 

 (full-rate equivalents) of insecticide this year, 0.9 DE's of 

 miticide, and 8.5 DE's (range of 5.4 to 12) of fungicide. 

 This reduction in overall pesticide use did not result in any 

 loss of crop quality, premature fruit drop, or other prob- 

 lems in these blocks. One spray-related problem was 

 brought to our attention which had appe2ired in some 

 locations: a russetted ring towEwd the low-hanging end of 

 the fruit. This injury was tentatively attributed to Captan 

 applied on a hot (88°?) day under poor drying conditions. 



Insects and Diseases in 1988 



European Apple Sawflv . Captures were quite high in 

 blocks where sawfly was not well controlled last year; one 

 block even exceeded our record high trap captures of 1987 

 with an average of 73 per trap and a maximum of 126! Trap 

 captures were moderate in most blocks; however, sawflics 

 entered in such a way that many growers were unable to 

 protect earlier cultivars when later cultivars were still in 

 bloom. Sawfly damage was seen in blocks where pre- 

 bloom sprays were applied as well as where such sprays 

 were withheld. 



Plum Curculio . Curculio activity also occurred in a 

 very concentrated period at bloom and petal fall. Injury 

 was exceptionally high in some blocks where controls 

 could not be applied in time. Very little fresh injury was 

 seen or reported in the 9 regular monitoring blocks after 2 

 to 3 weeks past petal fall. Some growers, particularly those 

 who often experience late curculio injury, did, however, 

 report serious problems with late curculio activity this 

 summer. 



Pear Thrips . This insect became a major problem in 

 at least 3 orchards in western Massachusetts as well as in 

 Vermont, causing poor fruit set in infested blocks (ap- 

 proximately 75% yield reduction in one case). Thrips have 

 been present in low-spray orchards in this area since 1985, 

 but this year was their first major appearance in commer- 

 cial blocks in Massachusetts. 



Leafminers . This year was another unusual year for 

 leafminer activity. Spring emergence seemed fairly stable 

 and predictable (unlike that of 1987, when cold and snow 

 made emergence highly erratic), and growers who had 

 leafminer problems, for the most part, were able to time 

 their sprays well. However, the second and third genera- 

 tions, increased to unexpectedly high levels, even where the 

 first generation appeared to be adequately controlled, or 



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