Abstract
The effectiveness of feeding barriers to protect seedlings against damage caused by pine weevil (Hylobius abietis) was evaluated in experiments established from 1995 to 1999 in southern Sweden. For this purpose the damage done to containerized seedlings protected by various types of barrier was evaluated, and compared with damage to untreated and insecticide (permethrin)-treated seedlings. Three types of feeding barrier that gave significant protection during the first 3 yrs were recognized: coating on the stem bark, shields with a collar at the top, and shields without a collar. The mean accumulated mortality caused by pine weevil for coatings (47%) and shields without a collar (59%) was significantly higher than the corresponding figure for permethrin treatment (13%), whereas shields with a collar (26%) did not differ significantly from the permethrin treatment in this respect. The highest mortality was found for untreated controls (87%).
Acknowledgments
This study was supported by the Swedish Hylobius Research Programme and the LF Research Foundation. Many people from Asa Forest Research Station have been involved in this study, especially Stefan Eriksson and Stefan Bergqvist. We thank Göran Nordlander for valuable comments on the manuscript. The language was corrected by John Blackwell.
Notes
Petersson, M. 1 , Örlander, G. 2 and Nilsson, U. 3 (1Swedish University of Agricultural Sciences, The Southern Swedish Forest Research Centre, Asa Forest Research Station, SE-360 30 Lammhult, Sweden, 2School of Industrial Engineering, Växjö University, SE-352 95 Växjö, Sweden, and 3Swedish University of Agricultural Sciences, The Southern Swedish Forest Research Centre, Box 49, SE-230 53 Alnarp, Sweden). Feeding barriers to reduce damage by pine weevil (Hylobius abietis).