Hostname: page-component-5c6d5d7d68-wpx84 Total loading time: 0 Render date: 2024-08-16T19:19:46.552Z Has data issue: false hasContentIssue false

A Comparison of the Developmental Rates of One- and Two-Year Cycle Spruce Budworm1

Published online by Cambridge University Press:  31 May 2012

R. F. Shepherd
Affiliation:
Laboratory of Forest Biology, Calgary, Alberta

Extract

The spruce budworm, Choristoneura fumiferana (Clem.), is indigenous to most of the boreal forests in Canada and adjacent Eastern and Western United States. Throughout most of this range the budworm maintains a one-year cycle, overwintering as second instar larvae. In some mountainous areas of Alberta and British Columbia, a form of the budworm has a two-year cycle and over-winters as second instar larvae in the first year and as fourth instar larvae in the second year. The habitat temperatures of these two forms were investigated and related to rates of development in an attempt to discover the environmental factor which maintains the two-year cycle budworm as a distinct form even though it is geographically surrounded by the one-year cycle budworm.

Type
Articles
Copyright
Copyright © Entomological Society of Canada 1961

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Brown, G. S. 1956. Studies of the spruce budworm in southern British Columbia. In Technical report of the forest insect survey for 1955 Interim report 1955–4, Forest Biology Laboratory, Victoria, B.C.Google Scholar
Freeman, T. N. 1958. The Archipinae of North America (Lepidoptera: Tortricidae). Can. Ent. 90, Supplement 7.Google Scholar
Harvey, G. T. 1957. The occurrence and nature of diapause-free development in the spruce budworm, Choristoneura fumiferana (Clem.) (Lepidoptera: Tortricidae). Can. J. Zool. 35: 549572.CrossRefGoogle Scholar
Mathers, W. G. 1932. The spruce budworm in British Columbia. For. Chron. 8: 154157.CrossRefGoogle Scholar
Rose, A. H. 1952. Investigation of the phenology of forest insects and their host trees. In Annual Technical Report, 1951, Forest Insect Laboratory, Sault Ste. Marie, Ontario.Google Scholar
Shepherd, R. F. 1958. Factors controlling the internal temperature of spruce budworm larvae, Choristoneura fumiferana (Clem.) Can. J. Zool. 36: 779786.CrossRefGoogle Scholar
Shepherd, R. F. 1960. Phytosociological and environmental characteristics of outbreak and non-outbreak areas of the two-year cycle spruce budworm, Choristoneura fumiferana. Ecology 40: 608620.CrossRefGoogle Scholar
Stehr, G. W. K. 1953. Investigations of the genetic structure of forest insect populations. Mim. Ann. Tech. Rpt. 1952, Forest Insect Laboratory, Sault Ste. Marie, Ontario.Google Scholar
Stehr, G. W. K. 1959. Hemolymph polymorphism in a moth and the nature of sex-controlled inheritance. Evolution 13: 537560.CrossRefGoogle Scholar