Trans. Kansas Acad. Sci. 23/24: 284. 1911,
Phenology: Capsules mature spring–fall (Mar–Oct).
Habitat: Soil banks along roads, trails, often on hummocks in clearings in woodlands, open or semishaded conditions
Elevation: usually low elevations
Man., N.B., Nfld. and Labr. (Nfld.), N.S., Ont., P.E.I., Que., Ark., Del., D.C., Ill., Ind., Iowa, Kans., Ky., Maine, Md., Mich., Minn., Mo., Nebr., N.H., N.Y., N.C., Ohio, Okla., Pa., S.D., Tenn., Va., W.Va., Wis.
Atrichum altecristatum is a common and widespread species, particularly in northcentral United States. It is distinguished from A. angustatum by the lamellae 4–6, and 4–6 cells high (against 6–9 lamellae, up to 15 cells high in A. angustatum), and leaf cells 24–28 µm in longest dimension, collenchymatous, with evident trigones (as opposed to cells smaller and subquadrate in A. angustatum, bulging mammillose on the adaxial surface). The difference in sexuality is more difficult to demonstrate, since most plants in a colony may appear female, with only a few shoots bearing a male inflorescence followed by a female inflorescence and sporophyte on the same stem about a centimeter above the male. As a result, the species is monoicous, but functionally dioicous. The taxon known as A. crispum var. molle (Holzinger) Frye evidently belongs here (R. R. Ireland 1969).