Observations on Hendersonia pinicola and the needle blight of Pinus contorta

Hendersonia pinicola, causal agent of a needle cast disease of Pinus contorta in the Pacific Northwest, induced initial disease symptoms and presented signs first in the lower parts of crowns and, later, in the upper parts of crowns. Ultimately, only distal parts of branches bore foliage. Diseased needles showed symptoms and signs at the apices, midsections, or both; needle bases remained green (...)