I found this species in 1929 in an open place on a sand hill in the edge of a black oak woods about a mile southwest of Plainville, Daviess County. It was reported by Wilson as being common in Hamilton and Marion Counties. It was also reported by Phinney from the area of Delaware, Jay, Randolph, and Wayne Counties. He says: "Fields and woods. Common." He also reports Gaura biennis and says: "Fields and woods. Rare." Phinney used Gray's Manual, edition 5, for his determinations and in it the distinction between the two species is not very clear and he may have confused them. I think both Phinney and Wilson made wrong determinations but I am not able to account for their errors. Munz (Bull. Torrey Bot. Club 65: 217. 1938) determined my specimen, collected near Plainville, Daviess County as Gaura filipes var. major T. & G. In 1938 Kriebel collected plants from the exact place where I collected my specimen and the sepals of all the specimens are less than 7 mm long, so I am referring all my specimens to the species.
Clumped perennial 6-15(-20) dm, with numerous, crowded lvs in the lower 1/3- 2/3 and long, subnaked, wand-like, branching infls, finely strigose throughout, varying to subglabrous or shortly spreading-hairy, with only the ovary, hypanthium, and sep strigose; lvs linear or linear-oblanceolate to lance-elliptic, entire or with a few coarse teeth, mostly 2-7 cm נ2-15 mm; bracts 1-2 mm, caducous; fls shortly slender-pedicellate, the pedicel at maturity of the fr (0.5-)1-3 mm, less than 0.5 mm thick; sep 5-12 mm, separately reflexed; pet 5-10 mm, turning pink; fr finely strigillose, 5-10 mm, fusiform, sharply 4-angled especially upwards; seeds 1 or 2; 2n=14. Dry woods and fields; Ky. and s. Ind. to S.C., Fla., and La. Aug., Sept. (G. michauxii)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.