Although the leaves of partridge pea are not as sensitive to touch as those of the related wild sensitive plant, they nevertheless have a degree of response which causes the thin little leaflets to move together when stroked down the midrib.
Cassia fasciculata Michx.
July - September Sands. fields. roadsides, ditches.
Partridge pea with its slender stems and soft little compound leaves is one of the common yellow Bowers of summer. In sandy fields and along country roads, in the grimy black coal dust of the coal mine country of southern Illinois, on the strip-mine tailings in northern Illinois, in poor soil and under poor conditions almost everywhere in the state, the partridge pea blooms from duly until late September.
The flowers are of irregular shape with five bright-yellow petals marked wiih a purple spot at the base of each, and a cluster of black-purple stamens and curving stiff pistil in the center. The asymmetrical shape not only is interesting, hut it is unlike the more compact, pea-shaped flowers of the Pea family to which it belongs. Partridge pea produces long, flat, thin green, then brown, pods with small brown seeds which are eaten by bob-whites and other seed-eating, ground-dwelling birds in 1llinois.
Wild senna (Cassia marilandica L.) grows three feet tall at the edges of woods and in low places in woods near water. The stem is tough and woody with long silky fibers running the length of the stalk. The leaves are compound and resemble those of black locust, and the flowers, shaped a good deal like those of partridge pea, are a deeper, more orange yellow with purple stamens, and are smaller, held in large clusters near the top of the stem.