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Species Agrilus bilineatus - Two-lined Chestnut Borer

Metallic Wood-boring Beetle - Agrilus bilineatus Two-lined Chestnut Borer - Agrilus bilineatus - male   - Agrilus bilineatus Buprestidae, dorsal - Agrilus bilineatus Buprestid  - Agrilus bilineatus Metallic Wood-boring Beetle - Agrilus bilineatus 2June2017.Lotus.HN.Coleo4-2 - Agrilus bilineatus Pennsylvania Beetle  - Agrilus bilineatus
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Coleoptera (Beetles)
Suborder Polyphaga
No Taxon (Series Elateriformia)
Superfamily Buprestoidea
Family Buprestidae (Metallic Wood-boring Beetles)
Subfamily Agrilinae
Tribe Agrilini
Genus Agrilus
Species bilineatus (Two-lined Chestnut Borer)
Explanation of Names
Agrilus bilineatus (Weber, 1801)
4-10 mm(1)
e NA to w. TX (QC-FL to SD-TX) - Map (2)(3)
Larvae are a major mortality agent of stressed oaks (Quercus), particularly red oaks (Muzika et al. 2000); adults feed on chestnut blight spores (Cryphonectria parasitica)(2)
Life Cycle
Overwinters in the prepupal stage in cells of the outer layer of sapwood and sometimes in the bark.(4)

Eggs are deposited on the bark in late spring or early summer. Young larvae bore through the bark to the phloem. They excavate winding mines in the inner bark and outer wood of the main truck and larger branches. These mines run back and forth in all directions.(4)
Substantial injury and mortality of American chestnut caused by A. bilineatus was noted as early as 1891; A. bilineatus was purportedly responsible for the death of 75% of the chestnut trees in Fairfax County, VA in 1893. Although largely ignored in the intervening decades, the beetle has been documented as a cause of oak mortality. (Muzika et al. 2000)
See Also
A. bilineatus carpini is now considered a distinct species

vittae less obvious, mostly just basally
Print References
Cote, W.A., III; Allen, D.C. 1980. Biology of twolined chestnut borer, Agrilus bilineatus, in Pennsylvania and New York. Annals of the Entomological Society of America. 73: 409-413.
Dunbar, D.M.; Stephens, G.R. 1974. Twolined chestnut borer: Effects of storage conditions, processing, and insecticides on its survival in oak logs. Journal of Economic Entomology. 67: 427-429.
Dunbar, D.M.; Stephens, G.R. 1975. Association of twolined chestnut borer and shoestring fungus with mortality of defoliated oak in Connecticut. Forest Science. 21: 169-174.
Dunbar, D.M.; Stephens, G.R. 1976. The bionomics of the twolined chestnut horer. In: J.F. Anderson and H.K. Kaya (eds.) Perspectives in forest entomology. Academic Press, New York. p.73-83.
Dunn, J.P.; Kimmerer, T.W.; Nordin, G.L. 1986. Attraction of the twolined chestnut borer, Agrilus bilineatus (Weber) (Coleoptera: Buprestidae), and associated borers to volatiles of stressed white oak. The Canadian Entomologist. 118: 503-509.
Dunn, J.P.; Kimmerer, T.W.; Nordin, G.L. 1986. The role of host tree condition in attack of white oaks by the twolined chestnut borer, Agrilus bilineatus (Weher) (Coleoptera: Buprestidae). Oecologia. 70: 596-600.
Haack, R.A. 1985. Management prescriptions for the twolined chestnut borer. In: J. Johnson (ed.) Challenges in oak management and utilization: Proceedings of a symposium; 1985 March 28-29. Madison, WI. University of Wisconsin-Madison, Cooperative Extension Service. p. 42-53.
Haack, R.A.; Benjamin, D.M. 1980. Influence of time of summer felling of infested oak trees on larval development and adult emergence of the twolined chestnut borer, Agrilus bilineatus. University of Wisconsin Forest Research Notes 236. University of Wisconsin, Department of Forestry, Madison, WI. 4 pp.
Haack, R.A.; Benjamin, D.M. 1982. The biology and ecology of the twolined chestnut borer, Agrilus bilineatus (Coleoptera: Buprestidae), on oaks, Quercus spp., in Wisconsin. The Canadian Entomologist. 114: 385-396.
Haack, R.A.; Benjamin, D.M.; Haack, K.D. 1983. Buprestidae, Cerambycidae, and Scolytidae associated with successive stages of Agrilus bilineatus (Coleoptera: Buprestidae) infestation of oaks in Wisconsin. Great Lakes Entomologist. 16: 47-55.
Haack, R.A.; Benjamin, D.M.; Schuh, B.A. 1981. Observations on the biology of Phasgonophora sulcata (Hymenoptera: Chalcididae), a larval parasitoid of the twolined chestnut borer, Agrilus bilineatus (Coleoptera: Buprestidae), in Wisconsin. Great Lakes Entomologist. 14: 113-116.
Muzika R.M., Liebhold A.M., Twery M.J. 2000. Dynamics of twolined chestnut borer Agrilus bilineatus as influenced by defoliation and selection thinning. Agricultural and Forest Entomology 2: 283–289. Full text
Wargo, F.M. 1977. Armillaria mellea and Agrilus bilineatus and mortality of defoliated oak trees. Forest Science. 23: 485-492.
WEBER, F. 1801. Observationes entomologicae, continentes novorum quae condidit generum characteres, et nuper detectarum specierum descriptiones. Kiliae, Universit. Buchh. pp. 12 + 116.
Works Cited
1.Field Guide to the Jewel Beetles (Coleoptera: Buprestidae) of Northeastern North America.
Paiero et al. 2012. Canadian Food Inspection Agency. 411 pp.
2.A catalog and bibliography of the Buprestoidea of America north of Mexico.
Nelson et al. 2008. The Coleopterists Society, Special Publication No. 4. 274 pp.
3.Global Biodiversity Information Facility (GBIF)
4.Eastern Forest Insects
Whiteford L. Baker. 1972. U.S. Department of Agriculture · Forest Service.