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Within-crown distribution, attack, and germination of Curculio occidentis-damaged and Cydia latiferreana-damaged Garry oak acorns in Victoria, British Columbia, Canada

Published online by Cambridge University Press:  28 May 2012

Imre S. Otvos
Natural Resources Canada, Canadian Forest Service, Pacific Forestry Centre, 506 West Burnside Road, Victoria, British Columbia, V8Z 1M5 Canada
Doris A. Mills
1111 Lakeshore Drive SW, Salmon Arm, British Columbia, V1E 4P1 Canada
Nicholas Conder*
Natural Resources Canada, Canadian Forest Service, Pacific Forestry Centre, 506 West Burnside Road, Victoria, British Columbia, V8Z 1M5 Canada
1Corresponding author (e-mail:


Garry oak, Quercus garryana Douglas ex Hooker (Fagaceae), is part of a unique ecosystem in British Columbia, Canada, which is rich in rare and endangered plant species. Garry oak recruitment is critical to the existence of this ecosystem, therefore, the effect of Curculio occidentis (Casey) (filbert weevil; Coleoptera: Curculionidae) and Cydia latiferreana (Walsingham) (filbertworm; Lepidoptera: Tortricidae) on acorn germination is of great interest. Together these two insects infested 80.7%, 75.1%, and 51.3% of acorns collected in 1996, 1997 (low crop years), and 1998 (high crop year), respectively. Filbertworm infestation did not vary with crown level. Filbert weevil infestation did not vary with crown level during poor crop years, but significantly more filbert weevil-infested acorns were found in the lower than the middle and upper portions of the trees during the high crop year. Severely damaged acorns did not germinate, and acorns with light to moderate feeding damage had lower germination success than undamaged acorns, but growth of germinated seedlings in the light to moderate damage category was unaffected. This study showed, for the first time, that these two insect species infested a large proportion of Garry oak acorns on the tree in British Columbia, and that light to moderate damage of the acorn has relatively low impact on seedling growth.


Le chêne blanc de Garry, Quercus garryana Douglas ex Hooker (Fagaceae), fait partie d'un écosystème unique de Colombie-Britannique, Canada, qui est riche en espèces de plantes rares et en péril. Le recrutement du chêne de Garry est essentiel à la survie de cet écosystème; c'est pourquoi les effets de Curculio occidentis (Casey) (charançon du noisetier; Coleoptera: Curculionidae) et de Cydia latiferreana (Walsingham) (mélissope des glands; Lepidoptera: Tortricidae) sur la germination des glands deviennent de grand intérêt. Ensemble ces deux insectes infestent respectivement 80.7%, 75.1% et 51.3% des glands récoltés en 1996, 1997 (années de production faible) et 1998 (année de production élevée). L'infestation des mélissopes des glands ne varie pas en fonction de la hauteur de la cime des arbres. L'infestation du charançon du noisetier ne varie pas en fonction de la hauteur de la cime durant les années de faible production; cependant, on trouve plus de glands infestés par le charançon du noisetier dans les étages inférieurs des arbres que dans les étages moyens et supérieurs durant les années de forte production. Les glands fortement endommagés ne germent pas et les glands qui sont légèrement à modérément endommagés par l'alimentation des insectes ont un succès de germination inférieur à celui des glands intacts, mais la croissance des jeunes plants issus des glands légèrement à modérément endommagés n'est pas affectée. Notre étude montre, pour la première fois, que ces deux espèces d'insectes infestent une forte proportion des glands du chêne de Garry encore sur les arbres en Colombie-Britannique et que des dommages faibles à modérés ont relativement peu d'impacts sur la croissance des jeunes plants.

Original Article
Copyright © Entomological Society of Canada 2012

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AliNiazee, M.T. 1981. Biology and control of the filbertworm, Melissopus latiferreanus. Proceedings of the Nut Growers Society of Oregon, Washington, and British Columbia, 66: 101103.Google Scholar
Andersson, C. 1992. The effect of weevil and fungal attacks on the germination of Quercus robur acorns. Forest Ecology and Management, 50: 247251.CrossRefGoogle Scholar
Association of Official Seed Analysts. 1978. Rules for testing seeds. Journal of Seed Technology, 3: 1126.Google Scholar
Barnett, R.J. 1977. The effect of burial by squirrels on germination and survival of oak and hickory nuts. American Midland Naturalist, 98: 319330.CrossRefGoogle Scholar
Beck, D.E. 1977. Twelve-year acorn yield in southern Appalachian oaks. United States Department of Agriculture, Forest Service Research Note SE-244, Southeastern Forest Experiment Station, Asheville, North Carolina.Google Scholar
Bernays, E.A. 1981. Plant tannins and insect herbivores: an appraisal. Ecological Entomology, 6: 353360.CrossRefGoogle Scholar
Boethel, D.J., Eikenbary, R.D., Bolte, J.R., Gentry, C.R. 1974. Sampling pecan weevil nut infestations: effects of tree, height and sector. Environmental Entomology, 3: 208210.CrossRefGoogle Scholar
Bonal, R., Muñoz, A., Díaz, M. 2007. Satiation of predispersal seed predators: the importance of considering both plant and seed levels. Evolutionary Ecology, 21: 367380.CrossRefGoogle Scholar
Bonner, F.T. 1984. Testing for seed quality in southern oaks. United States Department of Agriculture, Forest Service Research Note SO-306, Southern Forest Experiment Station, New Orleans, Louisiana, United States of America.Google Scholar
Bonner, F.T.Vozzo, J.A. 1987. Seed biology and technology of Quercus. United States Department of Agriculture Forest Service, General Technical Report SO-66, Southern Forest Experiment Station, New Orleans, Louisiana, United States of America.Google Scholar
Boucher, D.H.Sork, V.L. 1979. Early drop of nuts in response to insect infestation. Oikos, 33: 440443.CrossRefGoogle Scholar
Branco, M., Branco, C., Merouani, H., Almeida, M.H. 2002. Germination success, survival and seedling vigour of Quercus suber acorns in relation to insect damage. Forest Ecology and Management, 166: 159164.CrossRefGoogle Scholar
Brezner, J. 1960. Biology, ecology and taxonomy of insects infesting acorns. University of Missouri, Agriculture Experiment Station Research Bulletin, 726: 140.Google Scholar
Chapman, R.F. 1974. The chemical inhibition of feeding by phytophagous insects: a review. Bulletin of Entomological Research, 64: 339363.CrossRefGoogle Scholar
Crawley, M.J.Long, C.R. 1995. Alternate bearing, predator satiation and seedling recruitment in Quercus robur L. Journal of Ecology, 83: 683696.CrossRefGoogle Scholar
Dohanian, S.M. 1940. Melissopus latiferreanus as a pest of filberts in the Northwest. Journal of Economic Entomology, 33: 852856.CrossRefGoogle Scholar
Dunning, C.E., Paine, T.D., Redak, R.A. 2002. Insect–oak interactions with coast live oak (Quercus agrifolia) and Englemann oak (Q. engelmannii) at the acorn and seedling stage. In Proceedings of the 5th symposium on oak woodlands: oaks in California's changing landscape, San Diego, California, 22–25 October, 2001. Technical coordinators R.B. Standiford, D. McCreary, and K.L. Purcell. United States Department of Agriculture, Forest Service General Technical Report PSW-492, Southwest Research Station, Albany, California, United States of America. pp. 205–218.Google Scholar
Eikenbary, R.D.Raney, H.G. 1973. Intratree dispersal of the pecan weevil. Environmental Entomology, 2: 927930.CrossRefGoogle Scholar
Erickson, W.R. 1996. Classification and interpretation of Garry oak (Quercus garryana) plant communities and ecosystems in southwestern British Columbia. M.Sc. thesis, University of Victoria, Victoria, British Columbia.Google Scholar
Farrar, J.L. 1995. Trees in Canada. Fitzhenry and Whiteside Limited, Markham, Ontario.Google Scholar
Fenner, M. 1991. Irregular seed crops in forest trees. Quarterly Journal of Forestry, 85: 166172.Google Scholar
Feret, P.P., Kreh, R.E., Merkle, S.A., Oderwald, R.G. 1982. Flower abundance, premature acorn abscission, and acorn production in Quercus alba L. Botanical Gazette, 143: 216218.CrossRefGoogle Scholar
Fleck, D.C.Layne, J.N. 1990. Variation in tannin activity of acorns of seven species of central Florida oaks. Journal of Chemical Ecology, 16: 29252934.CrossRefGoogle ScholarPubMed
Fuchs, M.A. 2001. Towards a recovery strategy for Garry oak and associated ecosystems in Canada: ecological assessment and literature review [online]. Technical Report GBEI/EC-00-030, Environment Canada, Canadian Wildlife Service, Pacific and Yukon Region. Available from [accessed 8 August 2010].Google Scholar
Fuchs, M.A., Krannitz, P.G., Harestad, A.S. 2000. Factors affecting emergence and first-year survival of seedlings of Garry oaks (Quercus garryana) in British Columbia, Canada. Forest Ecology and Management, 137: 209219.CrossRefGoogle Scholar
Furniss, R.L.Carolin, V.M. 1977. Western forest insects. United States Department of Agriculture, Forest Service, Miscellaneous Publication 1339, Washington, District of Columbia, United States of America.CrossRefGoogle Scholar
Gibson, L.P. 1971. Insects of bur oak acorns. Annals of the Entomological Society of America, 64: 232234.CrossRefGoogle Scholar
Gibson, L.P. 1972. Insects that damage white oak acorns. United States Department of Agriculture, Forest Service Research Paper NE-220, Northeastern Forest Experiment Station, Upper Darby, Pennsylvania, United States of America.Google Scholar
Gibson, L.P. 1982. Insects that damage northern red oak acorns. United States Department of Agriculture, Forest Service Research Paper NE-492, Northeastern Forest Experiment Station, Broomall, Pennsylvania, United States of America.Google Scholar
Hosie, R.C. 1979. Native trees of Canada, 8th ed. Fitzhenry and Whiteside Limited, Don Mills, Ontario.Google Scholar
Jones, E.W. 1959. Biological flora of the British Isles: Quercus L. Journal of Ecology, 47: 169222.CrossRefGoogle Scholar
Kearby, W.H., Christisen, D.M., Myers, S.A. 1986. Insects: their biology and impact on acorn crops in Missouri's upland forests. Missouri Department of Conservation, Terrestrial Series Number 16, Missouri Department of Conservation, Jefferson City, Missouri, United States of America.Google Scholar
Koenig, W.D., Mumme, R.L., Carmen, W.J., Stanback, M.T. 1994. Acorn production by oaks in central coastal California: variation within and among years. Ecology, 75: 99109.CrossRefGoogle Scholar
Levin, D.A. 1976. The chemical defenses of plants to pathogens and herbivores. Annual Review of Ecology and Systematics, 7: 121159.CrossRefGoogle Scholar
Lewis, V.R. 1992. Within-tree distribution of acorns infested by Curculio occidentis (Coleoptera: Curculionidae) and Cydia latiferreana (Lepidoptera: Tortricidae). Environmental Entomology, 21: 975982.CrossRefGoogle Scholar
Mangini, A.C.Perry, R.W. 2004. The insect guild of white oak acorns: its effect on mast quality in the Ozark and Ouachita National Forests. In Ouachita and Ozark Mountains symposium: ecosystem management research, Hot Springs, Arkansas, 26–28 October, 1999. Edited by J.M. Guldin. United States Department of Agriculture, Forest Service General Technical Report SRS-74, United States Department of Agriculture, Forest Service Southern Research Station, Ashville, North Carolina, United States of America. pp. 79–82.Google Scholar
McQuilkin, R.A.Musbach, R.A. 1977. Pin oak acorn production on green tree reservoirs in southeastern Missouri. Journal of Wildlife Management, 41: 218225.CrossRefGoogle Scholar
Meidinger, D.Pojar, J. 1991. Ecosystems of British Columbia. British Columbia Ministry of Forests Special Report Series 6. British Columbia Ministry of Forests, Victoria, British Columbia.Google Scholar
Oliver, A.D.Chapin, J.B. 1984. Curculio fluvus (Coleoptera: Curculionidae) and its effects on acorns of live oaks, Quercus virginiana Miller. Environmental Entomologist, 13: 15071510.CrossRefGoogle Scholar
Peacock, J.W., Wright, S.L., Galford, J.R. 1988. Attraction of the acorn-infesting Cydia latiferreana (Lepidoptera: Tortricidae) to pheromone-baited traps. Great Lakes Entomologist, 21: 151156.Google Scholar
Peter, D.H.Harrington, C. 2009. Synchronicity and geographic variation in Oregon white oak acorn production in the Pacific Northwest. Northwest Science, 83: 117130.CrossRefGoogle Scholar
Rohlfs, D.A. 1999. A study of acorn feeding insects: filbert weevil (Curculio occidentis (Casey)) and filbertworm (Cydia latiferreana (Walshingham)) on Garry oak (Quercus garryana (Dougl.)) in the southeastern Vancouver Island area. M.Sc. thesis, University of British Columbia, Vancouver, British Columbia.Google Scholar
Sharp, W.M.Sprague, V.G. 1967. Flowering and fruiting in the white oaks. Pistillate flowering, acorn development, weather, and yields. Ecology, 48: 243251.CrossRefGoogle Scholar
Steel, R.G.D.Torrie, J.H. 1980. Principles and procedures of statistics: a biometrical approach, 2nd ed. McGraw-Hill Book Company, Toronto, Ontario.Google Scholar
Steele, M.A., Knowles, T., Bridle, K., Simms, E.L. 1993. Tannins and partial consumption of acorns: implications for dispersal of oaks by seed predators. American Midland Naturalist, 130: 229238.CrossRefGoogle Scholar
Stein, W.I. 1990. Quercus garryana Dougl. ex Hook. In Silvics of North America. Vol. 2, Hardwoods. Agricultural Handbook 654 . Technical Coordinators, R.M. Burns and B.H. Honkala. United States Department of Agriculture, Forest Service, Washington, District of Columbia, United States of America. pp. 650660.Google Scholar
Stephenson, A.G. 1981. Flower and fruit abortion: proximate causes and ultimate functions. Annual Review of Ecology and Systematics, 12: 253279.CrossRefGoogle Scholar
Swiecki, T.J., Bernhardt, E.A., Arnold, R.A. 1991. Monitoring insect and disease impacts on rangeland oaks in California. In Proceedings of the Symposium on Oak Woodlands and Hardwood Rangeland Management, Davis, California, 31 October–2 November, 1990. United States Department of Agriculture, Forest Service General Technical Report PSW-126. Technical Coordinator R.B. Standiford. United States Department of Agriculture, Forest Service Pacific Southwest Research Station, Berkeley, California. pp. 208–213.Google Scholar
Waller, J. 2006. The effects of filbert weevil (Curculio occidentis) and filbertworm (Cydia latiferreana) on Garry oak (Quercus garryana) acorn germination on Vancouver Island [online]. Vancouver Island University, Nanaimo, British Columbia. Available from [accessed 14 July 2011].Google Scholar
Weckerly, F.W., Sugg, D.W., Semlitsch, R.D. 1989. Germination success of acorns (Quercus): insect predation and tannins. Canadian Journal of Forest Research, 19: 811815.CrossRefGoogle Scholar
Williamson, M.J. 1966. Premature abscissions and white oak acorn crops. Forest Science, 12: 1921.Google Scholar