Skip to Main Content
Testing aerially applied Orthene for control of larch casebearer.Author(s): John S. Hard; Stanley Meso; Michael Haskett
Source: Res. Paper. PSW-138. Berkeley, CA: Pacific Southwest Forest and Range Experiment Station, Forest Service, U.S. Department of Agriculture. 6p
Publication Series: Research Paper (RP)
Station: Pacific Southwest Research Station
PDF: View PDF (818 KB)
DescriptionOrthene was tested in a randomized block experiment to determine efficacy against larch casebearer. Needlemining larval populations were sprayed in September 1976 by helicopter with 0.5 lb Orthene/gal water/acre (560 g a.i/9.3 l/ha). Spray deposit was sampled with Kromekote cards. Plot mean larval populations, spray deposit, and defoliation index were analyzed to detect significant differences among treatments by using twoway analyses of variance. Larval populations were reduced an average of 92.1 percent on the nine treated plots and an average of 40.5 percent on the three check plots. Defoliation index averaged light on treated plots and heavy on check plots the following spring. Percent parasitization of casebearing larvae by native parasitoids was higher on treated plots than on check plots the following spring. No operational spraying of casebearer should be done with Orthene in areas where parasitoids have been introduced, however, until the effect on introduced parasitoids is known.
- You may send email to firstname.lastname@example.org to request a hard copy of this publication.
- (Please specify exactly which publication you are requesting and your mailing address.)
- We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
- This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
CitationHard, John S.; Meso, Stanley; Haskett, Michael. 1979. Testing aerially applied Orthene for control of larch casebearer. Res. Paper. PSW-138. Berkeley, CA: Pacific Southwest Forest and Range Experiment Station, Forest Service, U.S. Department of Agriculture. 6p
Keywordsinsecticides, field tests, aerial spraying, Orthene, larch casebearer
- Field test with helicopter applications of Gardona against gypsy moth in Pennsylvania
- Control of douglas-fir tussock moth by aerially applied Dimilin (TH 6040)
- Introduced and Native Parasitoid Wasps Associated With Larch Casebearer (Lepidoptera: Coleophoridae) in Western Larch
XML: View XML