There are 11 species of this genus in the eastern United States, 9 of which are native. In general terms these are called hawkweeds, all members of the aster family. The most common of these is the alien king devil that dominates yards in late spring. The rattlesnake weed, however, is a native species that grows in open woods and clearings, favoring shady areas and sandy soils.

Like most hawkweeds, the rattlesnake weed has mostly a basal rosette of leaves and only a few, if any, stem leaves. The distinctive characteristic of this species is that the veins of these leaves are very thick and often colored a bright purple. In this manner the species is quite variable. The plant grows 1-2.5 feet tall and has dandelion-like flowers in open clusters at the ends of long thin flower stalks. These composite flowers have all ray florets and no central disk florets. The sap is milky.

The rattlesnake weed is not as common as some of the alien species, but worth looking for on forest trails.The origin of the common name is a matter of speculation. Some say it because it grows in the same habitat that rattlesnakes prefer, others that it was once used to treat snakebite. Others say it is because the leaves sometimes have the appearance of snake scales.