Abstract
Samples drawn from sites in Washington, Oregon, Idaho, and Montana were used to determine intrastand patterns of occurrence of the western spruce budworm. The insects were counted on 45-cm terminal branch tips and whole branches taken from the upper, middle, and lower crowns of short ( 14-m) Douglas-fir and grand fir trees. Only average trees were sampled for instar IV. Across all crown strata, tree height classes, budworm life stages, and budworm densities studied, density on whole branches could be estimated from density on 45-cm terminal tips. For each budworm stage, consistent density relations were usually found among both live crown thirds and the three tree height classes. None of the relations above differed between the populations on Douglas-fir and grand fir.
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.
