A method for sampling western spruce budworm pupae.

Nilima Srivastava; Roy C. Beckwith; Robert W. Campbell; Torolf R. Torgersen

doi:10.2737/PNW-RN-372

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A method for sampling western spruce budworm pupae.

Informally Refereed

Authors:

Nilima Srivastava, Roy C. Beckwith, Robert W. Campbell, Torolf R. Torgersen

Year:

1981

Type:

Research Note

Station:

Pacific Northwest Research Station

DOI:

https://doi.org/10.2737/PNW-RN-372

Source:

Res. Note PNW-RN-372. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Forest and Range Experiment Station 6 p

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Abstract

Pupal density of western spruce budworm, Choristoneura occidentalis Freeman, can be accurately estimated from 45-cm branch tips. Density on tips was representative of densities on entire branches. Mean pupal densities on branch tips are statistically different from lower, mid, and upper crowns (p = .07). Therefore, multi-crown sampling is required to precisely estimate the mean of populations similar to those used in this study.

Keywords

Population sampling, insect surveys, sampling methods, insect populations, western spruce budworm, Choristoneura occidentalis

Citation

Srivastava, Nilima; Beckwith, Roy C.; Campbell, Robert W.; Torgersen, Torolf R. 1981. A method for sampling western spruce budworm pupae. Res. Note PNW-RN-372. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Forest and Range Experiment Station 6 p