Douglas Fir - 100 Most Common North American Trees

Insects and Diseases of Douglas Fir

Pest information courtesy of USFS Fact Sheets
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Pests: Aphids infestations on small trees may be dislodged with a strong stream of water from the garden hose. Scale and bark beetles may infest Douglas-Fir, especially those under stress.

Diseases: Root rot can be a serious problem on clay and other wet soils. Needles infected by leaf cast fungi in spring turn brown and fall off. Several fungi cause canker diseases leading to branch dieback. Maintain tree health and prune out infected branches.

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