Cracca hispidula (Michx.) Kuntze
Galega hispidula Michx.
Tephrosia elegans Nutt.
Tephrosia gracilis Nutt.
Tephrosia hispidula is an erect or decumbent, herbaceous perennial plant growing from a slender, woody crown and a woody taproot up to 30cm long; the stems can be up to 50cm tall[
The plant is harvested from the wild for local use as a medicine.
The plant contains rotenonoids and has been used traditionally as a fish poison - rotenoids kill or stun the fish making them easy to catch, but the fish remain perfectly edible for mammals. Rotenonoids are classified by the World Health Organization as moderately hazardous. They are mildly toxic to humans and other mammals, but extremely toxic to many insects (hence their use as an insecticide) and aquatic life, including fish. This higher toxicity in fish and insects is because the lipophilic rotenonoid is easily taken up through the gills or trachea, but not as easily through the skin or the gastrointestinal tract. The lowest lethal dose for a child is 143 mg/kg, but human deaths from rotenone poisoning are rare because its irritating action causes vomiting. Deliberate ingestion of rotenone, however, can be fatal.
The compound decomposes when exposed to sunlight and usually has an activity of six days in the environment.
Southeastern N. America - Virginia, south to Florida then west to Louisiana
Dry to moist, or even wet, acid, sandy soils, chiefly in flat pinelands and savannahs[
The root is chewed and the juice is swallowed as a remedy for coughs[
]. If too much is chewed, when treating bad coughs, it can act as a laxative[
Pre-soak the seed for 12 hours in warm water and then sow in a greenhouse in spring. Prick out the seedlings into individual pots when they are large enough to handle and grow on in the greenhouse for their first winter, planting out in the following spring or early summer.