comparatively open cano- 

 pies that do not show a 

 significant disease re- 

 sponse to summer prun- 

 ing, therefore we did not 

 summer prune the blocks 

 for disease management. 

 In order to compare 

 disease impacts of the 

 SRC systems and a con- 

 ventional IPM system, we 

 observed disease inci- 

 dence in conventional 

 cultivars under normal 

 first-level IPM practices 

 using a block on each of 

 the three farms consist- 

 ing of conventional culti- 

 vars (Mcintosh, 

 Cortland, Delicious). We 

 did not compare these 

 blocks to the SRC blocks 

 for management of and 

 damage by arthropod 

 pests. 



Pesticide Use and 

 Injury 



Table 1 shows the 

 mean number of miticide 

 and insecticide treat- 

 ments applied to each 

 block. Table 1 also shows 

 the mean number of ar- 

 thropod-injured fruit at 

 harvest. We focus here on 

 fruit injury initiated after 

 early June, the time when 



second-level IPM practices against insects diverged 

 from first-level IPM practices. Injury by apple 

 maggot was slightly greater and injury by leafroller 

 was substantially greater in second-level compared 

 with first-level blocks. Very little injury by codling 

 moth or lesser appleworm occurred in these blocks. 

 Not shown are fruit injury levels caused by larvae in 

 one orchard that we identified as apple pith moth 

 larvae. This injury was slightly greater in the 

 second-level block, but definitive identification of 

 the larvae (new to us) is pending. 



Table 2 shows the number of fungicides applied 

 in the SRC blocks and the conventional blocks, as 

 well as the disease incidence in each block type. 

 Sooty blotch and flyspeck damage far exceeded any 



other fruit injury in each block type. This result was 

 not surprising, since several observations have 

 shown that in orchards which receive no fungicides 

 in Massachusetts, there will be significant levels of 

 sooty blotch and fiyspeck at harvest. In blocks of 

 standard cultivars, fungicide applications greatly 

 reduced sooty blotch and fiyspeck damage, but fiy- 

 speck remained the most damaging disease. 



Table 3 shows mean abundance of principal 

 arthropod pests of the fohage and their principal 

 natural enemies. Notable among pests is the lower 

 average European red mite population but the 

 higher average white apple leafhopper and rose 

 leafiiopper populations in the second-level blocks. 

 Notable among natural enemies is the substantially 



10 



Fruit Notes, Winter, 1994 



