This southeastern species occurs only east of the Mississippi Rv., mostly in sandy savannas, pocosins and bogs; it is rare outside the Coastal Plain. L. angustifolia has been discovered recently by M. Hines in an acid xerohydric meadow of LINC (NP). In Tenn., it is known from three counties, also in remnants of wet "barrens" on the Eastern Highland Rim (Ch, K). L. angustifolia has distinctly narrow leaflets, with L/W = 4-10, thus resembling virginica. However, the species is probably closest to hirta and capitata, sharing relatively large calices (at least as long as corollas and fruits), with lobes exceeding tubes; also corollas are white or creamy (versus purple to pinkish in other native species).