Abstract
The systemic insecticides acephate, dimethoate, and carbofuran were implanted into Douglas-fir trees, Pseudotsuga menziesii (Mirb.) Franco, at Oakridge, OR, and Willow Creek, CA, to evaluate their effectiveness in reducing seed and cone insect damage. The acephate-implant treatment significantly reduced seed damage by the Douglas-fir cone moth, Barbara colfaxiana (Kearfott) (Lepidoptera: Olethreutidae), and a cone gall midge, Contarinia oregonensis Foote (Diptera: Cecidomyiidae), and significantly increased the percentage of filled seed by 300% at the California site. Neither dimethoate nor carbofuran significantly affected any of the seed or cone insects encountered in this study. Acephate was not effective against a seed chalcid, Megastigmus spermotrophus Wachtl (Hymenoptera: Torymidae), nor the western conifer-seed bug, Leptoglossus occidentalis Heidemann (Heteroptera: Coreidae). The association observed between C. oregonensis damage and undeveloped seeds suggests that management strategies that include effective control measures should also include methods to monitor and reduce seed abortion.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
