Rhabdocline, Swiss Needle Cast and Didymascella

Needle Disease

Rhabdocline pseudotsugae - on Douglas-fir

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Apothecia on needles as they appear when dry.

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Apothecia on needles when they are wet. The epidermis lifts up off the apothecia and ascospores are released.

Phaeocryptopus gaeumannii - Swiss Needle Cast on Douglas-fir

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Douglas-fir with Swiss needle cast. Perithecia (numerous small black dots) can often be seen even without a hand lens if needles are inspected closely.

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Perithecia emerging from stomata on infected needles are easily seen with a hand lens.

Didymascella thujina - on Western Red Cedar

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Apothecia on lesions of western red cedar produce asci with 2 ascospores per ascus.