LEGUMINOSAE PULSE FAMILY 
PARTRIDGE PEA 
Cassia Chamaecrista L. 
The Partridge Pea grows in dry open places from Massachu- 
setts to Florida and west to Minnesota, Texas and Mexico. 
It is rather rare in the northern part of Illinois but is common 
farther south. 
The plant is an erect, 
widely branched annual 1-2% 
feet high. Its branches may 
be scantily hairy or entirely 
smooth. The 18-30 leaflets are 
somewhat sensitive to the touch 
and often fold up when the 
plant is handled. The petiole 
bears a cup-shaped gland below 
the lowest pair of leaflets. 
The showy yellow flowers 
are produced from July to 
September and in contrast to 
most members of this family 
are not butterfly shaped. The 
calyx is composed of 5 small 
green sepals only slightly 
united at the base. The 5 
yellow petals are slightly un- 
equal and usually 2 or 3 have 
a purple spot at the base. The 10 stamens are distinct 
and the anthers, 4 yellow and 6 purple, are unequal and pollen 
bearing. There is 1 pistil with a slender style and the fruit 
is a many-seeded pod which may be smooth or hairy. When 
the pod is fully mature it opens somewhat elastically, the halves 
twisting and throwing out the seeds. 
The commoner form in the south is the Large Partridge Pea, 
Cassia Chamaecrista L. var. robusta Pollard, which is stouter and 
very hairy. 
The Wild Sensitive Plant, Cassia nictitans L., is a small erect 
or spreading annual having numerous small compound leaves with 
10-44 leaflets, there being no odd terminal leaflet. Each leaf bears 
a small gland at the base of the stalk. The very small yellow 
flowers are totally inconspicuous, and they, together with its road- 
side habit, give it the appearance of a weed. This species is 
abundant along sandy stretches of road in southern counties, 
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