THE MONTHLY BULLETIN. 



43] 



write would probably l>e a repetition, but 1 will offer a few suggestions that will be 

 of interest especially to the commissioners of the state. If any county has been so 

 fortunate as to be entirely free from two of our serious pests there is reason for 

 thankfulness. Caltrop or ground burr nut (Tribulus terrestris) and the sand bun- 

 grass (Cenchrus tribuloides) are our worst weed pests. They are costing our 

 county thousands of dollars to control aside from the many thousands of dollars 

 damage to crops and stock. 



Fig. 137. The Caltrop or ground bur-nut, Tribulus terrestris. The 

 plant spreads over the ground in a dense mat heavily loaded with long 

 sharp hexagonal seed pods. The points of these seeds are sharp enough 

 to puncture an ordinary bicycle tire. (State Comm. of Hort. ) 



< (ne of my neighboring horticultural commissioners of the north writes and asks 

 if I do not think that to eradicate the caltrop in the county would be as expensive 

 as to eradicate the ground squirrel. Jly answer is "yes !" and emphatically so, if 

 eradication is possible, but this we have been unable to bring about but have thought 

 ourselves fortunate where we have been able to control it. So, my fellow horticul- 

 tural commissioner, if you are so fortunate as not to know these weeds, and not 

 having had them in your county. I would suggest that you send for specimens which 

 I would gladly supply. If only a light infestation is in your county stamp it out at 

 any cost. Here can be a demonstration of the possibility and practicability of com- 

 pletely eradicating this serious weed pest even at heavy expense. I believe there can 

 he nothing to hinder a weed campaign iu a district more than one weedy ranch on 

 which there has been no work done, and last but not least, I would say whatever is 

 begun finish at any cost. It may look pretty discouraging to begin some forced 

 work in a district where there are thousands or acres of weed-infested land, but as 

 soon as a single job has been finished with satisfactory results it carries more weight 

 and results than ever could be written into the statutes of the state of California or 

 voiced by the word of man. 



