The Carolina redroot or paint-root (Lachnanthes caroliana (Lamarck) Dandy) is native to marshes and open bogs ranging from Nova Scotia, where it is endangered, down the eastern seaboard to Florida, Mississippi and Cuba. Redroot is monotypic, the sole species in its genus, and according to current taxonomy, the only member of the Haemodoraceae, the bloodwort family present in North America. The bloodworts are generally found in the southern hemisphere—Africa, Australia, New Guinea and South America. ("Redroot", Species at Risk, Environment Canada, 2003)

Out of flower, redroot looks much like a thin scraggly iris; in flower, it is very distinct. It blooms in late summer and autumn, the branched inflorescence arising from the rhizome. The flowers are comprised of six tepals, three yellow on the adaxial (upper) side, three stamens, and a three-chambered ovary. It is distinct because the scape and flowers are covered in woolly fuzz—the generic name created from the Greek lachne, "soft, woolly hair", and antheros, "blooming".

Although redroot produces seeds, it propagates mainly by stolons (offshoots) from its rhizome. In shallow-water habitats, a single plant becomes a colony. Several years ago, I came across a small marsh in a forest clearing with numerous black swallowtail butterflies battling for a chance to feast at redroot flowers.

The rhizome contains a red sap hence redroot and paint-root. The sap was pressed from the rhizomes for dye and paint, but how the coloring was mixed or used is apparently unrecorded. (A Modern Herbal, Mrs. M. Grieve, 1931, reprinted Dover Publications, 1971)

Redroot pigment is considered toxic to albino and light-colored pigs. In the sixth edition of Origin of the Species (1869), Charles Darwin cites Jeffries Wyman, professor of anatomy at Harvard from 1847 to 1874. "...it appears that white sheep and pigs are injured by certain plants, while dark-colored individuals escape: Professor Wyman has recently communicated to me a good illustration of this fact; on asking some farmers in Virginia how it was that all their pigs were black, they informed him that the pigs ate the paint-root (Lachnanthes), which coloured their bones pink, and which caused the hoofs of all but the black varieties to drop off; and one of the "crackers" (i.e. Virginia squatters) added, "we select the black members of a litter for raising, as they alone have a good chance of living.""

In this writer's opinion, Professor Wyman's anecdotal evidence 'holds water'. I have found few intact colonies of redroot; feral hogs 'root' the plants from the soil. And I have blundered into litters of piglets with a white or mottled member, but of the adult pigs I've seen, all were black.