From Flora of Indiana (1940) by Charles C. Deam

Infrequent to frequent throughout the state. In moist sandy soil in prairie habitats or in extinct lake bottoms, it is often abundant over several acres. It prefers a moist, sandy soil but is found also in dry, gravelly soil and on rocky wooded slopes. It is generally found in moist places along streams, usually in open woods; in deep wooded ravines, in fallow fields, on open rocky wooded slopes, and along roadsides and railroads. A careful study of my 75 specimens shows that I have specimens of the typical form of the species and its variety [var. mollis]. Nearly all are intermediate in the kind and quantity of pubescence; plants typical of the variety will have some villous hairs about the nodes or on the petioles. The calyx tube varies from 5 to 9 mm long, its teeth from 1 to 2 mm long, and the surface is more or less densely glandular-puberulent. The leaves vary from ovate with rounded bases to those that are ovate-lanceolate to lanceolate with rounded, truncate or cuneate bases. Ordinarily the deep woods forms have broad leaves while those of dry habitats have narrower leaves. The color of the flowers also varies from a light to a deep purple. The habitat and distribution [of var. mollis] are the same as that of the [full] species. The under surface of the leaves of the typical form is velvety to the touch. The pubescence of the branches of the stem and under surface of the leaves in the variety [mollis] is densely canescent and the hairs on the stem are not at all spreading.

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Indiana Coefficient of Conservatism: C = 3

Wetland Indicator Status: FACU