Striped crotalaria C. mucronata Desv. Showy crotalaria C. spectabilis Roth Slenderleaf crotalaria C. intermedia Kotschy Lanceleaf crotalaria C. lanceolata E. Mey. Magness et al. All are upright growing summer annuals.
Stems are coarse and well branched except in thick stands.
Leaves are trifoliate, the leaflets varying in shape from linear to ovate. Crotalarias are adapted only to warm climates with a long growing season. They are resistant to the rootknot nematode and are valuable to reduce the nematode population in infested soils. They do well on soils of low fertility and are most used to turn into the soil for soil improvement. C. spectabilis contains an alkaloid poisonous to livestock.