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AGRICULTURE ON THE PACIFIC SLOPE 



FIG. 83. Seedling of mayweed. 

 (About natural size.) 



very rapidly. After the weed dies a perfect forest of 



little plants comes up where it lay the year before. 



If these are allowed to grow, 

 their tough, wiry roots make 

 it very hard to kill them. 



Mayweed, or dog fennel. 

 This is a great pest in the 

 East, and is rapidly spread- 

 ing in the Pacific states. Its 

 early stage is shown in figure 

 83. It grows two or three 

 feet high, and is completely 



covered with white daises with yellow centers. The seeds 



are light and are scattered everywhere by the wind. 

 Groundsel. This weed has about the same power 



to germinate in the dry sum- 

 mers as the bur clover has. 



It should be killed in the 



early stage shown in figure 



84. Its later leaves are of 



much the same shape as those 



shown in the figure. It has 



yellow flowers and fluffy 



white seeds, which may be 



carried a long distance by 



the wind. 



Horse weed (erigeron). This is chiefly troublesome 



in irrigated lands, where it grows to the height of eight 



FIG. 84. Young plant of 

 groundsel. (About natural size.) 



