Abortiporus biennis
Mycologia 36: 68. 1944.
Common Name: none
Fruiting body annual, terrestrial, fan-shaped to infundibuliform, pilei 8-18 cm broad, often clustered; margin level to uplifted, wavy; upper surface tomentose, white, pinkish, reddish-brown, tan to ochre-brown, faintly azonate; "aberrant fruitings" also produced, consisting of cauliflower-like masses, the entire surface poroid; context up to 1.0 cm thick, two-layered, upper layer soft-textured, lower layer leathery-pliant and tough; odor and taste untested.
Pores decurrent in stipitate specimens, 1-3 mm broad, angular, becoming labyrinthoid with lacerate mouths, white to buff, when fresh, often bruising or weathering pinkish to reddish-brown, sometimes exuding reddish droplets; tubes colored like the pores, up to 5 mm long; pores covering the entire surface in "aberrant fruitings."
Stipe if present, poorly developed, up to 5 cm long, 3 cm thick, lateral to central in attachment, well rooted and incrusted with dirt.
Spores 4.5-6.5 x 4.0-5.0 µm, ellipsoid to ovoid, smooth, hyaline, moderately thick-walled, hilar appendage inconspicuous, non-amyloid; chlamydospores present in context, 5.5-7.5 microns, globose, thick-walled; spore deposit not seen.
Solitary or in small groups in soil or grass near hardwood stumps, rarely with conifers; fruiting throughout the year in watered areas, e.g. parks and gardens, and in natural woodlands after the fall rains; uncommon.
Unknown.
This ground-dwelling polypore often puzzles collectors with its mixture of "normal" shelving clusters and "aberrant" cauliflower-like fruiting bodies. Despite the common name "Blushing rosette," which refers to the vinaceous hues seen in many fruitings, the color is actually quite variable, ranging from cream, reddish, ochre, to brown. A number of terrestrial polypores are similar. These include Polyporus tuberaster whose funnel-shaped, ochre-brown caps are squamulose, not tomentose, and Albatrellus species, which can be distinguished by pores that never become labyrinthoid, microscopically by the lack of chlamydospores, and a mycorrhizal habit. Phaeolus schweinitizii, which also sometimes forms "rosettes" on the ground, is generally larger, has mustard-olive pores nearing maturity, dark-brown when senescent, and saprobic on conifer roots or stumps, not hardwoods. Fresh, young specimens of Abortiporous biennis sometims exude red droplets, suggestive of Hydnellum pecki. The latter, however, is a tooth fungus.
— very young
