orchards, soil pH between the rows may still be near neutral. How- 

 ever, in the soil within rows the pH may be well below 5.0. It is 

 now recommended that lime be added in the rows of an older orchard 

 before it is removed. Using this method, the lime may be added 

 more precisely in the areas that require lime and not in the areas 

 between rows that do not require pH adjustment. 



In conclusion, it was interesting to observe the innovations 

 and contrasts of 'Mcintosh' culture in an area where orchards are 

 generally small and the weather during the growing season is dry 

 and sunny. Growers in British Columbia have cultural problems but 

 they are in many instances different from the ones in Massachusetts, 



*************** 



APPLE APHID CONTROL THROUGH NATURAL ENEMIES 



Roger G, Adams, Jr, and Ronald J. Prokopy 

 Department of Entomology 



Aphids are small soft-bodied, pear-shaped insects that may be 

 either winged or wingless. They may cause considerable injury to 

 apple and are most easily recognized by the presence of a pair of 

 tube-shaped structures known as cornicles at the end of their abdo- 

 mens. In this article, we discuss the apple aphid Aphis pomi and 

 its natural enemies in Western Massachusetts apple orchards. We 

 focus in particular on our research on the ecology of its major 

 predator, a midge. We conclude with new findings on spray mater- 

 ials which are least toxic to the midges and allow their build-up. 



The apple aphid, formerly known as the green apple aphid, may 

 be found in dense colonies on apple throughout the growing season. 

 Serious losses may result in commercial orchards if populations are 

 not suppressed. Apple aphid injury may be caused in a niimber of 

 ^ays . Feeding on fruits may result in the production of "aphis 

 apples," while foliar feeding may result in leaf curling and stunt- 

 ing of terminal growth. Aphid excretion of honeydew (a sticky, 

 sugary waste product visible as clear spots about 1/16 inch in diam- 

 eter on leaf and fruit surfaces) and subsequent growth of blackish 

 sooty mold fungus on the honeydew can result in reduced photosyn- 

 thetic activity of leaves and contamination of fruit. Recent evi- 

 dence that the apple aphid can artificially transmit the organism 

 causing fire blight in apples could lower the economic threshold 

 level for this pest. Currently, several sprays are required 



