The plant is found in the Midwestern and Eastern United States, Eastern Canada, and the Bahamas.<ref>USDA: Trichostema dichotomum distribution map</ref><ref>Kew World Checklist of Selected Plant Families</ref><ref>Biota of North America Program 2013 county distribution map</ref><ref>Wunderlin, R. P. 1998. Guide to the Vascular Plants of Florida i–x, 1–806. University Press of Florida, Gainesville</ref><ref>Gleason, H. A. & A.J. Cronquist. 1991. Manual of the Vascular Plants of Northeastern United States and Adjacent Canada (ed. 2) i–910. New York Botanical Garden, Bronx</ref>
Trichostema dichotomum is an annual herbaceous forb with opposite, simple leaves, and square, erect, hairy stems.
The flowers are blue, borne in late summer.<ref>Voss, E. G. 1996. Michigan Flora, Part III: Dicots (Pyrolaceae-Compositae). Cranbrook Inst. of Science, Ann Arbor.</ref>