Coefficient of Conservatism:
Coefficient of Wetness:
FROST ASTER, HAIRY ASTER
R. W. Smith
Aster pilosus of Michigan Flora.
Two rather well-marked varieties are found in Michigan, although apparent intergrades rarely occur.
Chiefly inland in the southern Lower Peninsula, with occasional plants in disturbed sites northward, is var. pilosum, with spreading whitish hairs on stems and leaves. This somewhat weedy variety occurs in dry to moist fields and prairies, along roadsides and shores, and even more extreme settings like pavement and concrete cracks at the edges of roads and sidewalks. It is quite late blooming and cold tolerant, and showy sometimes into early November, well deserving the common name frost aster.
Along and near the shores of the Great Lakes from Berrien and Huron Cos. north is var. pringlei (A. Gray) G. L. Nesom, with stems and leaves glabrous or nearly so. This is a calciphile, on sandy and gravelly shores and beaches, interdunal flats and swales, limestone pavements and other outcrops, rarely islightly inland. These plants, somewhat earlier blooming than var. pilosum, seem very distinctive, and warrant further study.
The bracts and leaves around the inflorescence often have spinulose tips; the awl-like appearance of these and the tips of the phyllaries make this a reasonably easy species to recognize. Rays are normally white, but rare pink forms are known.