DESCRIPTIONS OF SOME COMMON WEEDS IQI 



throughout the wheat growing sections of the state. The 

 seeds, like those of the corn cockle, are occasionally found 

 in wheat screenings. 



Wild Bean (Strophostyles pauciflora (Benth.) Watson). 

 Climbing herb; pinnately three-foliate and stipulate 

 leaves; leaflets lanceolate or linear-oblong; flowers two 

 to six, purplish ; seeds quadrate with truncate ends ; 

 pubescent. Common in fields in southern Iowa, Missouri 

 and southward to Texas. 



S. helveola is also an annual with ovate leaflets having 

 a prominent rounded lobe toward the base ; terminal leaf 

 two-lobed ; flowers greenish-white or purplish. Common 

 in sandy soil and fields from Minnesota and Wisconsin, 

 eastward and southward. 



Wood-sorrel Family (Oxalidaceae). Stemless or leafy- 

 stemmed herbs, with rootstocks or scaly bulbs, or rarely 

 shrubs; leaves mostly palmately three-foliate, or occa- 

 sionally pinnate or entire ; stipules small, merely an ex- 

 pansion of the base of the petiole ; flowers white, pink or 

 forking cymes, or sometimes solitary ; sepals five, often 

 unequal ; petals five ; stamens ten to fifteen ; ovary five- 

 celled, five-lobed; ovules two to many in each cavity; 

 fruit generally a capsule ; seed with endosperm ; embryo 

 straight. About 250 species, chiefly tropical. 



Yellow Wood-sorrel (Oxalis stricta, L.). A perennial 

 by subterranean shoots with erect stem either glabrous 

 or villous, without stipules ; flowers yellow, sepals five, 

 persistent, pistils five, stamens ten, pod oblong, mem- 

 branaceous, five-celled; seeds two or more in each cell. 

 Common eastward. 



The O. corniculata, like the preceding, strigose pubes- 

 cent, stipules round or truncate, pedicels longer than the 

 leaves, two to six-flowered. A cosmopolitan weed, but 

 much rarer than the preceding. 



Geranium Family (Geraniaceae). Herbs with alternate 

 or opposite, simple, or palmately trifoliate leaves; fre- 



