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Damage and symptoms of pine wilt nematode. Photo by: Robert Lambe, Virginia Polytechnic Institute and State University, Bugwood.org.
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Close-up of damage, one year after tree death. Photo by: USDA Forest Service – Rocky Mountain Region Archive, USDA Forest Service, Bugwood.org.
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Cerambycid (Longhorn) beetles transmit the nematode to susceptible trees. Photo by: L.D. Dwinell, USDA Forest Service, Bugwood.org.
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Nematode in an axial resin canal of Pinus densiflora. Photo by: Y. Mamiya, Bugwood.org.
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The nematodes also feed on blue stain fungi which often invade dead, dying, or fresh cut timeber. Photo by: USDA Forest Service – North Central Research Station Archive, USDA Forest Service, Bugwood.org.