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oak heart rot fungus

oak heart rot fungus (Inonotus dryophilus)
Illinois Status: common, native
Photo © Hank Guarisco

Features and Behaviors

FEATURES
The fruiting body is brown to red-brown above and white below. It is triangular to hoof-shaped with the upper surface sloping down, and the lower surface sloping up. Concentric color bands are apparent on the upper surface.

BEHAVIORS
This species produces a fruiting body on living oak trees that degrades quickly following spore dispersal. The fungus enters the tree most often through branch stubs but can also enter through tree wounds. It can create extensive decay in mature trees.

Illinois Range

Taxonomy

​Kingdom: Fungi
Phylum: Basidiomycota
Class: Basidiomycetes
Order: Hymenochaetales
Family: Hymenochaetaceae

Habitats

Aquatic Habitats
bottomland forests

Woodland Habitats
bottomland forests; upland deciduous forests

Prairie and Edge Habitats
edge