Hostname: page-component-586b7cd67f-gb8f7 Total loading time: 0 Render date: 2024-11-24T00:06:04.019Z Has data issue: false hasContentIssue false

DAMAGE PREDICTION FOR CONTARINIA OREGONENSIS FOOTE (DIPTERA: CECIDOMYIIDAE) IN DOUGLAS-FIR SEED ORCHARDS

Published online by Cambridge University Press:  31 May 2012

G.E. Miller
Affiliation:
Canadian Forestry Services, Pacific Forestry Centre, 506 West Burnside Road, Victoria, British Columbia, Canada V8Z 1M5

Abstract

Damage at cone harvest by the Douglas-fir cone gall midge, Contarinia oregonensis Foote, was positively correlated with the number of egg-infested scales per conelet in the spring. Reducing the average number of galled seeds per cone by 1.5 increased the average number of filled seeds per cone by 1.0 in insecticide trials. Optimum sample sizes for estimating average densities of egg-infested scales were calculated to be one conelet per tree and 150 trees per orchard. The mean crowding variable was linearly related to average density so a sequential sampling technique relative to a critical density, using Iwao’s procedure, was developed for determining the need of control actions.

Résumé

Une corrélation positive a été établie entre les dommages causés à la récolte de cônes par la cécidomyie des cônes du Douglas (Contarinia oregonensis Foote) et le nombre d’écailles infestées par cônelet au printemps. La réduction de 1,5 obtenue lors d’essais de répression avec des insecticides du nombre moyen des graines touchées par cône a entraîné une augmentation du nombre moyen de graines pleines par cône de 1,0. Les tailles optimales des échantillons pour l’estimation de la densité moyenne des écailles infestées d’oeufs ont été calculées comme étant d’un cônelet par arbre et de 150 arbres par verger. Un rapport linéaire existant entre la variable d’encombrement moyen et la densité moyenne, une technique d’échantillonnage progressif en fonction de la densité critique, selon la méthode d’Iwao, a été élaborée pour déterminer la nécessité de mesures de répression.

Type
Articles
Copyright
Copyright © Entomological Society of Canada 1986

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

Burts, E.C., and Brunner, J.F.. 1981. Dispersion statistics and sequential sampling plan for adult pear psylla. J. econ. Ent. 74: 291294.CrossRefGoogle Scholar
Cochran, W. 1977. Sampling techniques, 3rd ed. John Wiley and Sons, Toronto. 428 pp.Google Scholar
Fowler, G.W. 1983. Accuracy of sequential sampling plans based on Wald's sequential probability ratio test. Can. J. For. Res. 13: 11971203.CrossRefGoogle Scholar
Hedlin, A.F. 1961. The life history and habits of a midge, Contarinia oregonensis Foote (Diptera: Cecidomyiidae) in Douglas-fir cones. Can. Ent. 93: 952967.CrossRefGoogle Scholar
Iwao, S. 1968. A new regression method for analyzing the aggregation pattern of animal populations. Res. Popul. Ecol. 10: 120.CrossRefGoogle Scholar
Iwao, S. 1975. A new method of sequential sampling to classify populations relative to a critical density. Res. Popul. Ecol. 16: 281288.CrossRefGoogle Scholar
Iwao, S., and Kuno, E.. 1968. Use of the regression of mean crowding on mean density for estimating sample size and the transformation of data for the analysis of variance. Res. Popul. Ecol. 10: 210214.CrossRefGoogle Scholar
Iwao, S., and Kuno, E.. 1971. An approach to the analysis of aggregation pattern in biological populations. In Patil, G.P. et al. , (Eds.), Statistical Ecology, Vol. I. Penn. State Univ. Press, University Park.Google Scholar
Johnson, N.E. 1962. A possible sampling method for determining when to spray for control of the Douglas-fir cone midge. Weyerhaeuser Res. Note 49.Google Scholar
Johnson, N.E., and Hedlin, A.F.. 1967. Douglas-fir cone insects and their control. Can. Dep. For. Rural Develop., For. Bran., Dep. Publ. 1168.Google Scholar
Johnson, N.E., and Heikkenen, H.J.. 1958. Damage to the seed of Douglas-fir by the Douglas-fir cone midge. For. Sci. 4: 274282.Google Scholar
Lloyd, M. 1967. ‘Mean crowding’. J. Animal Ecol. 36: 130.CrossRefGoogle Scholar
Miller, G.E. 1980. Pest management in Douglas-fir seed orchards in British Columbia: a problem analysis. Simon Fraser University, Pest Management Paper 22.Google Scholar
Miller, G.E. 1983 a. When is controlling cone and seed insects in Douglas-fir seed orchards justified? For. Chron. 59: 304307.CrossRefGoogle Scholar
Miller, G.E. 1983 b. Biology, sampling and control of the Douglas-fir cone gall midge, Contarinia oregonensis Foote (Diptera: Cecidomyiidae), in Douglas-fir seed orchards in British Columbia. Ph.D. thesis, Simon Fraser University, Burnaby, British Columbia.CrossRefGoogle Scholar
Miller, G.E. 1984. Biological factors affecting Contarinia oregonensis infestations in Douglas-fir seed orchards on Vancouver Island, British Columbia. Environ. Ent. 13: 873877.CrossRefGoogle Scholar
Miller, G.E. 1986. Distribution of Contarinia oregonensis Foote (Diptera: Cecidomyiidae) eggs in Douglas-fir seed orchards and a method of estimating egg density. Can. Ent. 118: 12911295.CrossRefGoogle Scholar
Nyrop, J.P., and Simmons, G.A.. 1984. errors incurred when using Iwao's sequential decision rule in insect sampling. Environ. Ent. 13: 14591465.CrossRefGoogle Scholar
Onsager, J.A. 1976. The rationale of sequential sampling, with emphasis on its use in pest management. USDA Tech. Bull. 1526.Google Scholar
Shaw, P.B., Kido, H., Flaherty, D.L., Barnett, W.W., and Andris, H.L.. 1983. Spatial distribution on infestations of Platynota sultana (Lepidoptera: Torticidae) in California vineyards and a plan for sequential sampling. Environ. Ent. 12: 6065.CrossRefGoogle Scholar
Shepherd, R.F., Otvos, I.S., and Chorney, R.J.. 1984. Pest management of Douglas-fir tussock moth (Lepidoptera: Lymantriidae): A sequential sampling method to determine egg mass density. Can. Ent. 116: 10411049.CrossRefGoogle Scholar
Stauffer, H.B. 1983. Some sample size tables for forest sampling. Brit. Columbia Min. For. Res. Note 90. 50 pp.Google Scholar
Taylor, L.R. 1984. Assessing and interpreting the spatial distributions of insect populations. Annu. Rev. Ent. 29: 321357.CrossRefGoogle Scholar
Waters, W.E. 1955. Sequential sampling in forest insect surveys. For. Sci. 1: 6879.Google Scholar