Hymenopellis radicata, commonly known as the deep root mushroom, beech rooter, or the rooting shank, is a widespread agaric readily identified by its deeply rooted stalk (stipe).
Description The cap is medium to large, flat, grayish or yellowish brown and streaked, with a central hump and between wide. The surface of the cap is sticky or slimy when moist, with the underside displaying wide white gills, or lamellae. The brittle stalk tapers at both ends and is nearly white above to brown below the soil.McKnight, Kent H. and McKnight, Vera B.(1987) A Field Guide to Mushrooms North America. New York, NY: Houston Mifflin Company
The stem grows into a long deeply rooting tap root until it touches a piece of wood. This may grow up to 25 cm in length in some specimens.
Similar species It is similar to Oudemansiella longipes.
Ecology and uses This species has been recorded as a favored food of adults of the pleasing fungus beetle Tritoma mimetica; remarkably, for the larval of this beetle it seems to be deadly.Goodrich, Michael A. and Springer, Charles A. (1999): The Pleasing Fungus Beetles (Coleoptera: Erotylidae) of Nebraska. Transactions of the Nebraska Academy of Sciences 25: 53-71.Fulltext The related T.atriventris has also been recorded from this mushroom, but it does not seem to be a regular food source for that beetle species.Goodrich, Michael A. & Skelley, Paul E. (1994): Fungal host records for species of Tritoma (Coleoptera: Erotylidae) of America North of Mexico. Entomol. News 105: 289-294. PDF fulltext
The caps are reportedly edible by humans.
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