34^ IRRIGATION FARMING. 



plant with yellow or reddish-yellow twining stems, 

 which wind themselves around the stems of alfalfa, 

 clover, or similar plants, near the ground, taking its 

 nourishment from its host. It has small, colorless, 

 scale- like leaves, and produces clusters of ten or more 

 flowers, each of which contains four small grayish seeds 

 which are about half the size of the alfalfa seed. 

 These fall to the ground, where they remain until the 

 next season, when they germinate. The young dod- 

 der plant cannot live long in the ground, and unless it 

 finds a host plant, soon dies. Where it is abundant 

 the plants upon which it feeds assume an unhealthy 

 appearance, and finally die. Dodder can be killed by 

 cutting the hay before the dodder blossoms, or by 

 burning it, or by plowing the crop under and cultivat- 

 ing the land for a year or two in corn, potatoes, or 

 other plants which have stems so large that dodder 

 does not live upon them. The plant itself is an annual, 

 and if it is not allowed to go to seed it will die of its 

 own accord. To keep it from seeding, then, is impor- 

 tant, and this can be done by running the mowing 

 machine when the alfalfa is half grown, and allowing 

 the hay to wilt on the ground, or it may be raked off, 

 as desired. 



The workings of this pestiferous parasite are illus- 

 trated in Fig. 73, reproduced from the American Ag-ri- 

 adturist. From the seed (<?) a vine grows and clings 

 to the alfalfa stem (^) by the sucking root (r), through 

 which the dodder thereafter feeds upon the alfalfa sap, 

 the ground roots dying and the vine turning yellow. 

 The slight purplish flowers {^d') are borne in clusters 

 (a). The small dodder seed (^) can be removed by a 



