scholarly journals Ecology of outbreak populations of the western spruce budworm

Ecosphere ◽  
2021 ◽  
Vol 12 (7) ◽  
Author(s):  
Vincent Nealis ◽  
Jacques Régnière
Keyword(s):  
Spruce Budworm ◽  
Western Spruce Budworm

A method for sampling western spruce budworm pupae.

1981 ◽  
Author(s):  
Nilima Srivastava ◽  
Roy C. Beckwith ◽  
Robert W. Campbell ◽  
Torolf R. Torgersen
Keyword(s):  
Spruce Budworm ◽  
Western Spruce Budworm

Peroral bioassay of nucleopolyhedrosis viruses in larvae of western spruce budworm.

1981 ◽  
Author(s):  
Mauro E. Martignoni ◽  
Paul J. Iwai
Keyword(s):  
Spruce Budworm ◽  
Western Spruce Budworm

Chemistry and field evaluation of the sex pheromone of western spruce budworm,Choristoneura occidentalis, Freeman

1982 ◽  
Vol 8 (2) ◽  
pp. 339-350 ◽  
Author(s):  
H. T. Cory ◽  
G. E. Daterman ◽  
G. D. Daves ◽  
L. L. Sower ◽  
R. F. Shepherd ◽  
...  
Keyword(s):  
Sex Pheromone ◽  
Spruce Budworm ◽  
Field Evaluation ◽  
Choristoneura Occidentalis ◽  
Western Spruce Budworm

Baculoviruses in populations of western spruce budworm

2015 ◽  
Vol 127 ◽  
pp. 76-80 ◽  
Author(s):  
V.G. Nealis ◽  
R. Turnquist ◽  
B. Morin ◽  
R.I. Graham ◽  
C.J. Lucarotti
Keyword(s):  
Spruce Budworm ◽  
Western Spruce Budworm

scholarly journals Aerial field tests of five insecticides on western spruce budworm in Idaho and Montana, 1978-1980

1986 ◽  
Author(s):  
George P. Markin ◽  
David R. Johnson
Keyword(s):  
Field Tests ◽  
Spruce Budworm ◽  
Western Spruce Budworm

RELATIONSHIPS BETWEEN ATTACK RATES AND SURVIVAL OF WESTERN SPRUCE BUDWORM, CHORISTONEURA OCCIDENTALIS FREEMAN (LEPIDOPTERA: TORTRICIDAE), AND BUD DEVELOPMENT OF DOUGLAS-FIR, PSEUDOTSUGA MENZIESII (MIRB.) FRANCO

1992 ◽  
Vol 124 (2) ◽  
pp. 347-358 ◽  
Author(s):  
Roy F. Shepherd
Keyword(s):  
Close Association ◽  
Spruce Budworm ◽  
Larval Survival ◽  
Douglas Fir ◽  
Choristoneura Occidentalis ◽  
Western Spruce Budworm ◽  
Bud Development ◽  
Feeding Sites ◽  
Vegetative Buds ◽  
Wide Range

AbstractIndividual larvae of western spruce budworm (Choristoneura occidentalis Freeman) were observed from overwintering emergence to pupation at six locations spread over a wide range of altitudes and thus climate. A weekly census of 100 lower-crown buds per plot indicated large differences in rates of bud development and larval survival among locations.Emerging second-instar larvae attempted to mine swelling buds of Douglas-fir. If the buds were hard and tight, larvae mined 1-year-old needles until penetrable buds were available. Larvae dispersed over the crowns with only one larva becoming established in each bud; thus, many early-emerging and surplus larvae could not find suitable feeding sites and disappeared. Within the protective bud, survival was high. After buds flushed and larvae became exposed, densities dropped, probably due to increased predation and decreased food quality. Correlations indicated a close association between larval survival for the exposed period between bud flush and pupation, and overall larval survival.Douglas-fir trees responded to initial bud removal, but not to needle removal, by inducing latent buds in the axils of needles to grow into active vegetative buds ready to develop and flush the next spring. The number of these new vegetative buds formed was greatest when the initial buds were removed early in the season before flush, and decreased thereafter. Trees with vigorous crowns had the greatest response to defoliation by inducing the largest number of latent buds into becoming active vegetative buds; these were found mainly on the 2- and 3-year-old internodes.

INFLUENCE OF FOLIAR NITROGEN LEVELS ON SURVIVAL, DEVELOPMENT, AND REPRODUCTION OF WESTERN SPRUCE BUDWORM, CHORISTONEURA OCCIDENTALS (LEPIDOPTERA: TORTRICIDAE)

1985 ◽  
Vol 117 (1) ◽  
pp. 23-32 ◽  
Author(s):  
J. Wayne Brewer ◽  
John L. Capinera ◽  
Robert E. Deshon ◽  
Mary L. Walmsley
Keyword(s):  
Larval Mortality ◽  
Spruce Budworm ◽  
Dry Weight ◽  
Douglas Fir ◽  
Nitrogen Level ◽  
Pupal Weight ◽  
Western Spruce Budworm ◽  
Foliar Nitrogen ◽  
Nitrogen Levels ◽  
White Fir

AbstractThe influence of nitrogen levels in foliage of white-fir, Abies concolor, and Douglas-fir, Pseudotsuga menziesii, seedlings on various biological characteristics of the western spruce budworm, Choristoneura occidentalis Freeman, was studied. Seedlings were grown under greenhouse conditions and provided with nutrient solutions to maintain five foliar nitrogen levels ranging from 1.29 to 4.42% dry weight for white fir and 1.43 to 3.94% for Douglas fir. Larvae confined to treated seedlings were monitored through the next generation. Larval mortality was higher, and development time longer, at both upper and lower extremes of foliar nitrogen than at mid-level. Mean pupal weight was significantly greater for larvae reared on white fir with the mid-range foliar-nitrogen level. Mean number, and weight, of eggs laid were highest when larvae fed on foliage from the mid-range nitrogen level. Total number of larvae produced was lowest at the high and low extremes of foliar nitrogen levels.

Toxicity of Zectran to Western Spruce Budworm as a Function of Application Site1

1971 ◽  
Vol 64 (5) ◽  
pp. 1307-1308
Author(s):  
C. F. Tiernan ◽  
R. P. Miskus
Keyword(s):  
Spruce Budworm ◽  
Western Spruce Budworm
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