not generally targeted, but may flare up in the absence of 

 organophosphate sprays. These were grouped as incidental 

 pests, and damage within this group was dominated by stink 

 bugs. The pattern of control of these pests (Table 8) was 

 very smiilar to the pattern of internal Lepidoptera. In each 

 sampling interval, treatment with either Surround or Imidan 

 (0.8% and 0.8% damage at harvest, respectively) signifi- 

 cantly reduced damage by incidental pests such as stink bugs 

 in comparison with untreated control ( 1 .8% damage at har- 

 vest). As with internal Lepidoptera, the bulk of injury was 

 observed to occur in early August. All told, control of these 

 incidental pests by Surround was consistently comparable 

 to control provided by Imidan. 



Conclusions 



Data from this study strongly confirm the potential ef- 

 fectiveness of alternative chemicals to replace Imidan or 

 Guthion for control of common apple insect pests. We are 

 particularly encouraged by the fact that Actara provided 

 control of both European apple sawfly and plum curculio 

 nearly equal to control provided by calendar sprays of 

 Imidan. Somewhat discouraging, though, are recent devel- 

 opments surrounding labeling of Actara. It has not yet re- 

 ceived a federal label for use in the 2001 growing season 

 and will not include apple maggot (not studied here) in its 

 near-term use recommendations. Even so, when labeled, 

 this material may offer a reasonable alternative to Imidan or 

 Guthion for control of early-season pests, particularly PC. 



There is no question from this and other studies that 

 Surround can provide very good season-long control of many 

 (if not all) common insect pests of apple fruit in the North- 

 east. However, we find several weaknesses in large-scale, 

 season-long use of this material; (1) difficulty of handling 

 and distributing each application effectively (at 25-75 lbs. 



per acre); (2) risk of wash-off of effective residue by rain- 

 fall, which dictates nine treatments per season; (3) need to 

 keep rapidly expanding fruit and foliage completely and 

 uniformly covered throughout the growing season; (4) cost 

 of a season-long Surround program ($225-5675 per acre, 

 depending on tree size and treatment interval); and (5) the 

 challenge of thoroughly rinsing clay residue after harvest. 

 In addition, there are a few negative pest management im- 

 pacts that have not been fully studied, such as suppression 

 of beneficials (particularly predaceous mites and leafminer 

 parasitoids) and the potential for rapid buildup of second- 

 ary pests that can quickly proliferate if spray coverage is not 

 ideal (such as is suspected for San Jose scale). We believe 

 that Surround may still hold potential as an insect manage- 

 ment tool in small-scale, limited-spray progranK, though 

 application of this material at any scale is challenging, par- 

 ticularly with a backpack sprayer (as in Fruit Notes, Sum- 

 mer 1999). 



Given slow progress toward labeling (and reported in- 

 effectiveness against AMP) of Actara, along with the han- 

 dling problems and potential expense of Surround, we will 

 not pursue large-scale testing of either material of the 2001- 

 2002 growing season. 



A cknowledgntents 



We would like to thank the Horticultural Research Cen- 

 ter in Belchertown for hosting this trial, along with Joe Sincuk 

 and Alex Clark for applying the experimental treatments. 

 Funding for this project was provided by the manufacturers 

 of the tested materials, Syngenta (Actara) and Engelhard 

 (Surround). Additional project funding was provided by state 

 and federal IPM funds and a grant from the Massachusetts 

 Society for Promoting Agriculture. 



"k ic 'k i: i: 



Fruit Notes, Volume 65, 2000 



27 



