Murray & Burpee (1984) Ceratobasidium gramineum (Ikata & T. Matsuura) Oniki, Ogoshi & T. Araki (1986) sensu auct.

Ceratobasidium cornigerum is saprotrophic, but is also a facultative plant pathogen, causing a number of economically important crop diseases, and an orchid endomycorrhizal associate.

[3] Corticium cornigerum was first described in 1922 by mycologist Hubert Bourdot, who found it growing in France on dead stems of Jerusalem artichoke.

[4] Molecular research, based on cladistic analysis of DNA sequences, places Ceratobasidium cornigerum within the genus Rhizoctonia, but this taxonomic problem has yet to be resolved.

[2] The following taxa belong in the Ceratobasidium cornigerum complex and have been treated as synonyms or as closely related but independent species: The basidiocarps (fruit bodies) are effused, thin, and whitish.

[2] If treated as a single species, Ceratobasidium cornigerum is cosmopolitan and has been reported from Asia, Australia, Europe, North & South America.

It occurs as a soil saprotroph, producing basidiocarps on dead stems and fallen litter, but is also a facultative plant pathogen causing disease of crops and turf grass.

[11][12][13] Early symptoms will include reduced vigor and a decrease in the ability to survive high water conditions.

[11][12][13] Infected plants may continue to grow but will show aboveground symptoms including stunting, decreased fruit size, and numerous dead older leaves.

[13] In the early stages of infection, the core of the root will appear white while the exterior begins to show black lesions.

[11][12][13] Black root rot is not usually introduced into the new planting through nursery stock or contaminated equipment but is instead often due to one or more of the disease-causing fungi already present in the soil.

[12] Pre-planting fumigation may suppress the disease during the year of planting, but typically it does not offer any lasting control and cultivars resistant to black root rot are not currently available.

In 1920 a Rhizoctonia species was first assigned as the causal pathogen responsible for "dying out" of strawberry beds in western Washington.

[23] Ceratobasidium ochroleucum (Corticium stevensii) was described causing a blight of apple and quince trees in Brazil,[24] but the name is of uncertain application because of confusion with Rhizoctonia noxia.