DESCRIPTIONS OF SOME COMMON WEEDS 



213 



to provide for germination and for sufficient growth of 

 stem to enable the plant to reach some other plant into 

 which it immediately sends its suckers and thus becomes 

 established upon its host from which it afterwards ob- 

 tains its nourishment. Dodders contain no green color- 

 ing matter, or chlorophyll as it is called, so are unable to 

 assimilate raw material and make starch of it as green- 

 leaved plants do, hence are dependent upon other plants 

 for nourishment that has already been 

 converted. Such plants are called par- 

 asites. Dodder seeds retain their vital- 

 ity five years or more, hence must be 

 considered as especially pernicious 

 when present in commercial seeds. 



Clover Dodder (Cuscuta Epithymum, 

 Murr.). Slender, reddish stems; cap- 

 itate flowers with pink calyx, corolla 

 with four to five erect lobes ; scales large, 

 incurved ; stemless, exserted, filiform 

 stamens; capsule circumsessile with 

 withering corolla. Found in both 

 clover and alfalfa; native to Europe, 

 but now found in the United States 

 from New England to Iowa and South 

 Dakota, the Rocky Mountains and the 

 Pacific coast. The large seeded Chil- 

 can dodder (C. racemosa, var. chiliana) 

 is found in clover seed sent from Chili. 



Field Dodder (Cuscuta arvensis, Beyrich). Pale yel- 

 low, filiform stems ; flowers in small, nearly sessile clus- 

 ters ; calyx of five obtuse lobes ; corolla nearly campanu- 

 late, five-lobed, longer than the tube, tips reflexed ; scales 

 large, ovate ; stamens not exserted ; style shorter than the 

 ovary ; stigmas capitate ; capsule globose, indehiscent. A 

 parasite on shrubs and various herbs as well as on clover 

 and alfalfa from New England to Florida, Canada to the 



Fig. 1363. Clover 

 on alfalfa. 



