Identification of Armillaria species from Wisconsin and adjacent areas
Single-spore isolates from 218 basidiomata
of Armillaria from Wisconsin, the upper peninsula of Michigan, and eastern Minnesota were identified to species by pairing with known haploid testers. Collec- tions were made from 25 different host species and were identified as A. ostoyae, A. gallica, A. calvescens, A. mellea, or A. sinapina. The most frequently collected species were A. ostoyae and A. gallica. Within the sam- pling area, A. ostoyae and A. sinapina were collected only in the northern portions, and A. mellea was col- lected predominantly in the southern portions. A r - millaria gallica and A. calvescens were collected throughout the area. Armillaria sinapina and A. ostoyae basidiomata were found equally on gymnosperms and angiosperms, whereas the other three species were collected predominantly from angiosperms. In addi- tion to the basidiomata collections, 71 cultures of A r - millaria were isolated from roots and rhizomorphs in seven 10- to 20-year-old quaking aspen stands in northern Wisconsin. These were subsequently iden- tified by pairing with known haploid testers; A. sina- pina and A. ostoyae were recovered most often, whereas A. gallica was isolated less frequently. In comparison with the other species, A. ostoyae was more frequently isolated from lesions on otherwise healthy roots and from roots of recently killed trees. On this basis, A. ostoyae appeared to be more pathogenic on aspen than
either A. sinapina or A. gallica.
Banik, M.T.; Paul, J.A.; and Burdsall, Jr., H.H., "Identification of Armillaria species from Wisconsin and adjacent areas" (1995). Aspen Bibliography. Paper 2017.