Partridge Pea, Prairie Senna, Golden Cassia, Chamaecrista fasciculata (Michx.), Native Minnesota Wildflower plant, Eloise Butler Wildflower Garden

(Prairie Senna, Golden Cassia, Sensitive Pea, Large-flowered Sensitive Pea). Partridge Pea is an annual and usually only noticed along the path edges as it does not grow over 2 1/2 feet high and young plants can be as short as 4" with a single flower as some of the photos below indicate. The stem often branches making the plant as wide as it is tall, which causes larger plants to sprawl. Stems are green and smooth, except young stems may have fine hair. Leaves are pinnately compound with 8-15 pairs of unstalked leaflets, each entire, lance shaped and tipped with a sharp bristle. The leaf has a pair of awl shaped stipules at the base of its stalk and on the stalk is a small gland, either sessile or with a very short stalk. Leaves are sensitive to daylight and fold the leaflets toward each other with darkness. Flowers occur from the leaf axils, sometimes 2 to 4 together, on long slender stalks, quite showy, up to 1 1/2" wide with 5 bright yellow petals that are about equal size. Three to four however have red at the base. Ten stamens of unequal length with purple anthers on 6, yellow on 4. The style is greenish-white. Beneath the petals are 5 green linear sepals. Seed: Fertile flowers mature into a flat straight pod that is green and slightly hairy, turning dark brown and smooth at maturity at which time they split with a twisting action which can fling the seeds away from the plant. Toxic: See bottom of page.

Habitat: Partridge Pea requires full to partial sun and dryer upland sites. It is invasive if not controlled and toxic to animals. Names: Partridge Pea was formerly classified in the genus Cassia, one of the Sennas where it was named Cassia chamaecrista L. The older name of Sensitive Pea is based on the leaflets being sensitive to daylight as explained above. The genus name, Chamaecrista (and the former species name) is from the Greek and is used for plants that have sensitive leaves and pods that suddenly split to eject the seed. The species, fasciculata, refers to a bundle of nerve fibers, again, referencing the sensitiveness of the leaflets.

	Plants of the Eloise Butler Wildflower Garden
	Common Name	Scientific Name	Plant Family	Garden Location	Prime Season
	Partridge Pea	Chamaecrista fasciculata (Michx.) Greene	Pea (Fabaceae)	Upland	Late Summer to Early Autumn
Other names and notes	(Prairie Senna, Golden Cassia, Sensitive Pea, Large-flowered Sensitive Pea). Partridge Pea is an annual and usually only noticed along the path edges as it does not grow over 2 1/2 feet high and young plants can be as short as 4" with a single flower as some of the photos below indicate. The stem often branches making the plant as wide as it is tall, which causes larger plants to sprawl. Stems are green and smooth, except young stems may have fine hair. Leaves are pinnately compound with 8-15 pairs of unstalked leaflets, each entire, lance shaped and tipped with a sharp bristle. The leaf has a pair of awl shaped stipules at the base of its stalk and on the stalk is a small gland, either sessile or with a very short stalk. Leaves are sensitive to daylight and fold the leaflets toward each other with darkness. Flowers occur from the leaf axils, sometimes 2 to 4 together, on long slender stalks, quite showy, up to 1 1/2" wide with 5 bright yellow petals that are about equal size. Three to four however have red at the base. Ten stamens of unequal length with purple anthers on 6, yellow on 4. The style is greenish-white. Beneath the petals are 5 green linear sepals. Seed: Fertile flowers mature into a flat straight pod that is green and slightly hairy, turning dark brown and smooth at maturity at which time they split with a twisting action which can fling the seeds away from the plant. Toxic: See bottom of page. Habitat: Partridge Pea requires full to partial sun and dryer upland sites. It is invasive if not controlled and toxic to animals. Names: Partridge Pea was formerly classified in the genus Cassia, one of the Sennas where it was named Cassia chamaecrista L. The older name of Sensitive Pea is based on the leaflets being sensitive to daylight as explained above. The genus name, Chamaecrista (and the former species name) is from the Greek and is used for plants that have sensitive leaves and pods that suddenly split to eject the seed. The species, fasciculata, refers to a bundle of nerve fibers, again, referencing the sensitiveness of the leaflets.