PULSE FAMILY 



LEGUMINOSAE 



TRAILING WILD BEAN 



Strophostyles helvola (L. ) Britton 



The Trailing Wild Bean is found throughout the eastern 

 half of the United States. In Illinois it is common on sand 

 ballast along railroads and on sandy shores of streams and ponds, 

 and is found also in open woods where the 

 soil is sandy. The blooming season is July 

 to October, so that flowers and mature fruits 

 may often be found together. 



This is a low twining or trailing annual 

 vine that branches from the base and has 

 stems 2-8 feet long. The leaflets may be 

 either 3-lobed or entire and the lateral ones 

 are often somewhat i-sided. 



The peduncles occur in the axils of thq 

 leaves and each bears 3-10 flowers in a cluster 

 at the end. The greenish purple flowers are 

 butterfly shaped, and the 5-toothed calyx has 



the 2 upper teeth a 

 little shorter than the 

 rest. The standard 

 is nearly round and 

 the 2 wing petals are 

 oval or oblong. The 

 long and slender keel 

 is strongly incurved 

 and encloses the sta- 

 mens and style. Fila- 

 ments of 9 of the 10 

 stamens are united 

 and the other is free. The pistil develops into a nearly cylindrical, 

 slightly hairy, several-seeded pod. 



The Pink Wild Bean, Strophostyles umhellata (Muhl.) Britton, 

 is a slender trailing perennial whose stems are clothed with back- 

 ward pointing hairs. The unlobed leaflets are oblong, blunt and 

 hairy on both sides. The pink flowers, one-half inch long, are 

 on long peduncles in umbels that look like heads. The straight 

 and slender pods are slightly flattened, about 2 inches long and 

 somewhat hairy. The plant favors dry sandy ridges, knolls and 

 dunes from Long Island to Illinois, south to Florida and Louisiana. 



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