WEEDS AND WEED CONTROL 



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inches tall beset with narrow, linear, alternate leaves. The flowers are 

 labiate, spurred and yellow in color produced through the summer. The 

 capsule is ovoid, two celled and filled with fifty to sixty flattened rough, 

 wing-margined seeds. Small areas of this weed may be controlled by 

 strong herbicides such as hot brine, or caustic soda. The use of a cultiva- 

 tor tends to spread the weed. Hoes and hand labor are more effective. 

 Persistent cutting will cause the rootstocks to starve to death. 



PIG. 107. Ox-eye daisy (Crysanthemum leucanthemum). Common in the East. 

 (Division of Bot., U. S. Dept. of Agriculture.) (Reproduced in Pommel, L. H.: Some 

 Weeds of Iowa. Bull. 70 Experiment Station, Iowa State College, 1903, p. 337.) 



Ox-eye Daisy (Chrysanthemum leucanthemum pinnatifidum) . The 

 stems of white daisy are tufted from one to three feet high bearing a head 

 of flowers with white marginal ones and yellow disc florets. The root 

 leaves are in a rosette and are spatulate, pinnatifid. The achenes, which 

 are found as an impurity in nearly all grass seeds, are grayish-black and 

 finely ribbed without peppers. Clean seed only should.be sowed. The 

 daisy field can be cleansed by short rotations, as the perennial roots are 



