This genus is included in the taxonomic designation "Hyphomycetes". It is a known allergen, causing Type I allergies (examples: hay fever, asthma). Phaeohyphomycotic sinusitis has been reported in connection with this mold. (See phaeohyphomycosis.)
Existing mainly in the temperate northern hemisphere, it can be found in soil, moist wood or cellulose materials, on decomposing plants, and as pathogens on living plants (leaf spots are one example). Colonies grow rapidly, and appear velvety to cottony in texture; coloring is light brown or olive green to black. Though it is rare to find indoor colonization, it has been found in dust that is transferred in from outside, including dust on air filters.