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scab. Nustar was superior to other materials. These materials can be applied 

 on an after-infection basis up to 96 hours following the initiation of an 

 infection. Next season, the upper limits of this time will be tested. In 

 addition, an application of one or more of these materials will be made this 

 fall to determine whether they have any effect on the ability of the fungus to 

 overwinter and produce ascospores in the spring. The tests at the HRC 

 represented a 150% increase over such tests in previous years. 



There were no reports this year of the bud blast or cankering attributed 

 to fire blight on Marshall Mcintosh. The summer may have been too cool for 

 development of the disease, though fire blight did show up in at least one 

 commercial orchard. Alternatively, dormant copper or Bordeaux treatments or 

 in-season streptomycin may be alleviating the problem. 



New or Unusual Outbreaks 



Potato leafhopper - Widespread leaf yellowing of apple throughout 

 Massachusetts has been identified by New York state entomologists as injury 

 caused by the potato leafhopper. Leaf injury, a diffuse yellowing of 

 consecutive terminal leaves, results from PLH feeding, during which leafhoppers 

 inject a toxic saliva. Injury shows up later, often after leafhoppers have 

 left. With no insects present, PLH injury can easily be mistaken for nutrient 

 deficiency. PLH does not overwinter in the region, but is "imported" from 

 southern states as storms move up the coast. Because the summer of 1986 was 

 characterized by a greater than normal frequency of such storms, PLH numbers on 

 several crops were unusually high. 



Catfacing insects on peaches - Catfacing continued well into the summer on 

 peaches in many locations this year, with injury occurring at one monitored 

 site in early August. The causative agent is not known, although a rather 

 damaged specimen which may have been oak hickory plant bug showed up on an AMF 

 sphere in late July. We will be monitoring the situation closely in 1987 to 

 determine if other pests such as stink bugs might be causing this injury. 



European corn borer - A grower located close to a corn field experienced 

 late season damage from ECB - larvae tunneling into the calyx and through the 

 core of the fruit. Growers in similar situations would be well advised to 

 monitor ECB populations in August and September. Also, early in the season, 

 one grower reported damage to terminal growth of young trees apparently caused 

 by an insect larva which was collected and tentatively identified as ECB. 



Plans for 1987 



We will be increasing the number of monitored orchards from 6 to 10 in 

 1987; two of these sites will very likely be low-spray orchards. In addition, 

 we will be monitoring a number of peach and pear blocks for borers, catfacing 

 insects, psylla, and peach X-disease as well as other problems which may become 

 apparent . 



The INFONET computerized bulletin board, operated in cooperation with Dr. 

 Wesley Autio, Department of Plant and Soil Sciences, will be maintained and 

 expanded in 1987. This BBS is the primary means of disseminating topical pest 

 management and horticultural information, pesticide registration news, meeting 

 dates, etc. to regional agents and other interested parties. INFONET will 



