This variable species is widely scattered in varied habitats across North America, but it is uncommon to rare in most eastern states (NS). In Ky. most records date from before 1950, and there are only 5-10 records from after 1980. The general decline in this species might be attributed to loss of transitional habitat (between woodland and grassland) plus overgrazing: "The plant is palatable to livestock and deer and is highly nutritious at certain times of the growing season" (Jensen 1997). Most colls. from Ky. may be referable to var. carolinianum (L.) M.E. Jones, which is centered in the Appalachians; this taxon tends to have a more open raceme with smaller flowers. Typical var. canadensis is centered in the Mississippi Valley (Barneby 1964). However, this taxonomic distinction may be unclear, and it is not accepted in most recent treatments (Isely 1990; K, W).