Instar development of the Douglas-fir tussock moth in relation to field temperatures.

Roy C. Beckwith; David G. Grimble; Julie C. Weatherby

doi:10.2737/PNW-RN-512

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Instar development of the Douglas-fir tussock moth in relation to field temperatures.

Informally Refereed

Authors:

Roy C. Beckwith, David G. Grimble, Julie C. Weatherby

Year:

1993

Type:

Research Note

Station:

Pacific Northwest Research Station

DOI:

https://doi.org/10.2737/PNW-RN-512

Source:

Res. Note PNW-RN-512. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 6 p

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Abstract

Instar development is recorded for the Douglas-fir tussock moth (Orgyia pseudotsugata) for two different elevations in the Boise National Forest, Idaho, in 1991. The percentage of the population by instars is associated with accumulated degree-days after eclosion, which can be used to predict the proper timing for spray application. For all practical purposes, areas can be released for spraying when third instars are initially found.

Keywords

Douglas-fir tussock moth, insects, larval development, aerial application

Citation

Beckwith, Roy C.; Grimble, David G.; Weatherby, Julie C. 1993. Instar development of the Douglas-fir tussock moth in relation to field temperatures. Res. Note PNW-RN-512. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 6 p