Inonotus dryadeus in North America:: new records, hosts, distribution and incidence

Inonotus dryadeus is newly reported in eastern Canada (Ontario) on Acer platanoides and Acer saccharinum, both new hosts, and Ulmus americana. The host range, incidence, and available distributional data in continental North America are summarized in a table. The fungus occurs primarily on Quercus, Abies, and Tsuga. Occasionally, it is found on Picea and Pinus as well as many other hardwood trees. Colder climates and host differences in the boreal forests may be limiting distributional factors. Inonotus dryadeus appears to favour very old trees. The maximum known width of the fruiting body is revised upward to 74.9 cm.