IDENTIFICATION OF ARMILLARIA SPECIES IN CALIFORNIA

Mating experiments were conducted with 30 California isolates of Armil laria species to determine their intersterility grouping. Basidiomes w ere collected from a variety of coniferous and hardwood hosts in urban , agricultural and forested regions in northern and central California . Monosporous cultures were obtained and paired with haploid tester st rains representing 10 North American biological species. A majority of the California isolates were compatible with Armillaria mellea sensu stricto (= North American biological species VI). The exceptions were four isolates from a low elevation, coastal forest. Three of these wer e compatible with North American biological species IX, a still uniden tified Armillaria species, and one was compatible with A. gallica (= N orth American biological species VII). These findings show that Armill aria species diversity exists in California, but that A. mellea predom inates on several hosts and in diverse habitats.