Tinder Polypore

IUCN Red List

not listed

NatureServe

not listed

Minnesota

not listed

Tinder Polypore fruiting body (conk) is a 2″ to 8″ wide, ¾″ to 4¾″ thick polypore.

The fruiting body is hoof-shaped, rounded and curved downward on top, flat or slightly angled upward below. There is no stalk.

The upper surface is concentrically zoned and hairy when young. The zones are grooved and vary in color in shades of gray and brownish-gray. It soon becomes gray and hairless. The margin is whitish and velvety on actively growing conks.

The underside is whitish. The pore tubes are not layered (stratified).

The flesh is hard and cinnamon brown. When cut in cross section there are no white lines (mycelial threads) visible.

An individual conk can survive for years, even decades, forming a new ridge or furrow each year. It is found on standing or fallen dead trees or on the trunk of a living tree.

Similar Species

Willow Bracket (Phellinus igniarius) old conks are black and are often cracked above. The margin and undersurface are light brown and velvety on actively growing conks. The pores are stratified. The flesh in cross section shows white mycelial threads.

Usually birch, but also other hardwoods

Tinder Polypore causes white trunk rot on hardwood trees. It turns the wood into a soft, white, spongy mass.

Season

Year-round, but it grows mostly in early summer and autumn

Tinder Polypore is named for its most common usage, as tinder for starting fires. Otzi the Iceman, the 5,000-year-old mummy found in the Alps in 1991, was carrying four pieces of it.