XVI International Botanical Congess

The diversity and distribution of macrofungi intrigue both amateur mushroom hunters and professional mycologists. For over 30 years, the North American Mycological Association has sponsored forays that have recorded species occurrence across the continent. Although foray reports prior to 1997 are not backed by specimens, they do provide an interesting resource to examine macrofungal diversity and distribution. For example, there have been five forays at Priest Lake, Idaho, 231 to 359 species were recorded per foray giving a total of 812 species names for this area. Only 4% of these species were reported for all five years while 60% were only recorded once. Jaccard=s coefficient of similarity ranged from 0.22 to 0.31 between pairs of Idaho forays. This low overlap between forays is due in part to yearly variation, timing of the foray, and collecting and identification biases of the participants. Species records at NAMA forays are now being documented by voucher specimens housed at The Field Museum enabling more rigorous analysis of macrofungal biodiversity. With time, these vouchered records will provide data on the distribution of macrofungi in North America and serve as a resource for further studies.