THE MONTHLY BULLETIN. 



27 



YELLOW STAR THISTLE. 



i ('• ntaurea solstitialis.) 

 By O. W. Newman. 



The yellow star thistle lias been known in California for the past 

 #0 years, and during that time has spread throughout the Sacramento 



Valley, and is 1 oming, \\ ith its lesser relative, the Napa thistle, a very 



serious menace to the grain areas of the state. It is found also in the 

 San Joaquin Valley and in parts of southern California, but it has 

 not as ye1 become a recognized pest in these regions. It is spreading 

 with great rapidity, especially along the main arteries of travel, and 

 unless some definite control action is undertaken the same condition 

 may arise in this state which occurred in the Dakotas in the year 1892 

 over Russian thistle. The following quotation from Bulletin 15, United 

 States Department of Agriculture, 1894, will show what the situation 

 was in those states : 



"In the badly infested areas more than 040.000 acres are devoted to wheat 

 raisin?. The average loss on this land, which may be attributed to the Russian 

 thistle alone, can not be less than five bushels per acre; and 3,200.000 bushels 

 at the minimum price of 50 cents per bushel (which is considerably less than 

 the average price) indicates a loss to the farmers in the Dakotas of .$1,600,000. 

 The loss in other crops, the injuries caused by the spines, and the fires caused 

 by the plants jumping fire breaks, will bring the total loss to something more 

 than $2,000,000 for the year 1S92." 



Yellow star thistle. Centaur ea solstitialis, is a naturalized weed 

 brought over from Europe at a very early date. Dr. "William Darling- 





Fig. 6. — Yellew ?tar thistle showing the 

 spines, leafless stems and the long, thick tap- 

 root. This thistle often reaches a height of 

 four feet. (Original.) 



