This annual may be widespread in western regions of the state but further study is needed. Pennell (1929, 1935; B) applied this name to plants from Ky., distinguished by their longer calyx lobes (ca. 1-2 mm versus 0.2-1 mm) and larger capsules (ca. 5-7 mm long versus 3-4 mm). There are records from BREC (PH), EDMO (PH) and elsewhere (B). Robinson (1960) also segregated such plants in much of c. and w. Tenn. Pennell treated var. macrophylla as a largely midwestern taxon, often on lowlands. He mapped typical tenuifolia mostly in more eastern states, centered on the Appalachians and generally on dry or sandy soils.