Can a Band of Tangletrap Around 

 a Tree Trunk Suppress Plum 

 Curculio Injury to Fruit? 



Ronald Prokopy 



Department of Entomology, University of Massachusetts 



Operators of small apple orchards and homeowners 

 have for decades been on the lookout for effective ways 

 of controlling plum curculio (PC) without having to 

 resort to use of insecticidal sprays. Approaches such 

 as daily tapping of tree branches to dislodge PCs 

 followed by removal fallen PCs from a cloth sheet 

 placed beneath the tree canopy have proven ineffective. 

 So also have a variety of non-toxic sprays designed to 

 repel PCs (such as sprays of garlic). We know from 

 studies by colleagues in Quebec that PCs enter and 

 leave apple tree canopies almost on a daily basis as 

 they search for food and egglaying sites and thereafter 

 shelter. We also know from some of our own behavioral 

 observations that during cool weather and also during 

 night hours, PCs tend to enter apple tree canopies by 

 crawling up tree trunks, whereas durine warm weather 



they tend to enter tree canopies by flight. 



Here, we asked whether a band of Tangletrap 

 around a tree trunk could prevent PCs from entering 

 the tree canopies to an extent that afforded protection 

 of fruit against injury. 



Materials & Methods 



The study was carried out in 2002 in a block of 

 unsprayed frees at the UMASS Cold Spring Orchard 

 Research and Educational facility in Belchertown. Half 

 of the frees were Mcintosh, and half were Delicious. 

 All were bearing trees on M.26 rootstock. Trees were 

 pruned in such a way that none of the branches of any 

 tree involved in the study touched the branches of any 

 adiacent tree or touched the eround. Herbicide 



Q 

 HI 



3 



a: 



LU 



o 



UJ 

 Q. 



60 



50 

 40 

 30 

 20 

 10 

 



■ Tangletrap-Banded 

 D Non-Banded 



ii_ 



w 



2 3 4 



WEEKS AFTER PETAL FALL 



Figure \. Percent of sampled fruit injured by plum curculio on Tangletrap-banded and non 

 banded apple trees. 



Fruit Notes, Volume 68, Winter, 2003 



13 



