Basidiospores of Armillaria mellea Survive an Alaskan Winter on Tree Bark. Charles G. Shaw III, Forestry Sciences Laboratory, Pacific Northwest Forest and Range Experiment Station, USDA Forest Service, Juneau, AK 99802. Plant Dis. 65:972-974. Accepted for publication 5 March 1981. This article is in the public domain and not copyrightable. It may be freely reprinted with customary crediting of the source. The American Phytopathological Society, 1981. DOI: 10.1094/PD-65-972.

Sterile distilled water was applied to the outer bark of 28 western hemlock (Tsuga heterophylla) and 26 Sitka spruce (Picea sitchensis) trees growing at three different locations in southeast Alaska. Runoff was incubated for up to 5 wk on Kuhlman’s medium. Colonies of Fomes annosus developed from runoff collected from 2 hemlock and 1 spruce, and colonies of Armillaria mellea from 12 hemlock and 8 spruce. Most A. mellea cultures had morphological characteristics commonly associated with single spore isolates. Because collections were made in March and April, 3–4 mo after sporophore production by A. mellea, basidiospores of A. mellea apparently survived the winter on the outer bark of sampled trees.