Hydnoporia tabacina

Scientific name:  Hydnoporia tabacina (Sowerby)
Spirin, Miettinen & K.H. Larss.
Derivation of name: Tabac- means "tobacco" as in its
color or odor.  In this case, the epithet refers to the color.
Synonyms: Hymenochaete tabacina (Sowerby) Lev.,
Stereum tabacinum (Sowerby) Fr.  
Common name(s):  Reddish-brown crust.
Phylum:   Basidiomycota
Order:   Hymenochaetales
Family:   Hymenochaetaceae
Occurrence on wood substrate:  Saprobic; forming
overlapping clusters of stalk-less caps on decaying
hardwoods; year-round. 
Dimensions:  Caps are 1-2 cm wide, 6-10 mm long, and
capable of fusing into effused-reflexed sheets 20-30 cm or
more long.   
Description: This effused-reflexed species forms
spreading crusts with small shelf-like, stalkless,
overlapping caps. The upper, sterile cap surfaces are
brownish, hairy to smooth, and concentrically zoned. The
lower, fertile cap surfaces and the effused areas are
brown, smooth to minutely cracked, and covered with
numerous dark brown setae (spines) which can be seen
with a hand lens.       
Edibility: Inedible.   
Comments: The cap surface stains black with KOH.


Figure 1.  Occurrence of Hydnoporia tabacina on a
decaying branch. Photo © Gary Emberger.

Figure 2. Note the flat effused portion composed of
laterally fused basidiocarps and the stalkless, shelflike,
overlapping reflexed caps. Photo © Gary Emberger.

Figure 3. These conical setae cover the fertile surface
in great numbers. They are quite visible with a 15X or
20X hand lens.
Photo © Gary Emberger.