Texas sensitive pea

Chamaecrista flexuosa, the Texas sensitive pea or wavy partridge-pea, is a slender perennial herb or subshrub in the Fabaceae family, native to the southern United States, Mexico, Central America, the Caribbean and much of tropical South America, where it grows in open savannas, sandy soils, pine flatwoods, roadsides and disturbed grasslands. The plant produces several ascending to spreading, flexuous, finely pubescent stems 20 to 80 centimetres long arising from a slender woody base. The alternate, pinnately compound leaves are 2 to 6 centimetres long and bear 10 to 30 pairs of small, linear-oblong, opposite leaflets with rounded to mucronate tips; the leaves show weak sensitive movement, partially folding when touched or at night. A small cup-shaped petiolar gland is borne on the petiole. The flowers are solitary or in small axillary clusters, each about 1 to 2 centimetres across with five slightly unequal bright yellow petals; the stamens are dimorphic with curved anthers. The fruit is a flat, linear, dehiscent legume 2 to 5 centimetres long that twists open to release several seeds.