WEEDS OF MONTANA. 65 



ground in many parts of the state and seeds spread by stock and 

 by irrigation. Rarely troublesome here in cultivated land. 

 [Fig. 21.] 



134. *XANTHIUM SPINOSUM, L. Thorny Cucklebur. 



Specimens of this weed have been sent in from the vicinity of 

 Victor and the plant is said to be well established about 

 sheep camps in the Bitter Root region, probably brought in 

 from the Pacific Coast with imported sheep. It has burs like the 

 preceding but the leaves are more lobed and white beneath with 

 long, three-divided yellow thorns in the axils. It should not be 

 allowed to secure a footing in the state lest it become a serious 

 pest to the wool industry and to agriculture. 



