Like all "Tylopilus" species, "T. felleus" is mycorrhizal. It is found in deciduous and coniferous woodland, often under beech and oak in well-drained acid soils, which can be sandy, gravelly or peaty. If encountered on calcareous (chalky) soil, it will be in moist areas that have become waterlogged and have ample leaf litter. Fruit bodies grow singly or in small groups, and occasionally in small clusters with two or three joined at the base of the stem. Fruit bodies have also been growing in the cavities of old trees, on old conifer stumps, or on buried rotten wood. The fungus obtains most of its nitrogen requirements from amino acids derived from the breakdown of proteins, although a lesser amount is obtained from the amino sugar glucosamine (a breakdown product of chitin, a major component of fungal cell walls). The mycorrhizal plant partner benefits from the fungus's ability to use these forms of nitrogen, which are often abundant in the forest floor. Fruit bodies appear over summer and autumn, anytime from June to October or even November, in many of the northern temperate zones. Large numbers may appear in some years, and none in others, generally proportional to the amount of rainfall. Variety "uliginosus", known from Michigan, grows among lichens and mosses under pines.