LEGUMINOSAE PULSE FAMILY 
WILD BEAN. GROUNDNUT 
Apios tuberosa Moench 
Many a country boy has rooted out and eaten the pear- 
shaped tubers of the Wild Bean. These tubers are said 
to have been used commonly in colonial days as a sub- 
stitute for bread. 
Because of them 
the plant is often 
called Groundnut. 
The Wild Bean 
grows in moist places 
from New Brunswick 
to Florida and west 
to Ontario, Minne- 
sota, Kansas and 
Texas, and blooms 
from July to Septem- 
ber. It is a beautiful 
vine whose slender 
twining stems climb 
over bushes to a 
height of several feet. 
The leaflets of the 
alternate compound leaves are usually 5 or 7, and there are 
stipules which soon drop off. 
The flowers are brownish purple. The calyx is somewhat 
2-lipped, the 2 lateral teeth being very small, the 2 upper united 
into I which is very short, and the lower 1 longest and pointed. 
The butterfly-shaped corolla has 5 petals and in this case the 
standard is turned back somewhat and the long keel is incurved 
and twisted. There are 10 stamens, g united and 1 free. The 
simple pistil develops into a many-seeded pod. 
Another Wild Bean, sometimes called Kidney Bean, Phaseolus 
polystachyus (L.) BSP., is fairly common on dry rocky hillsides 
in open woods. From the thick fleshy root springs the smooth 
green stem which is conspicuous for its unusual length. Some- 
times it climbs over bushes 12 feet away from its rooting place. 
The purple flowers are small but handsome, in racemes through 
summer and fall. The calyx is 5-toothed or cleft with the 2 upper 
teeth often shallower, and the drooping pods are 4 or 5-seeded. 
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