20 THE MONTANA EXPERIMENT STATION. 



sorrel (Rumex Acetosella) are nearly as difficult to eradicate and 

 much worse to spread than the Canada thistle, but fortunateh- 

 they have as yet appeared in but few localities in the state. They 

 should be treated in much the same way as the Canada thistle 

 above. For lawn weeds which tend to spread and crowd out the 

 grasses, such as dandelion, plantain, chick weed (Cerastium vul- 

 gare), rosin-weed (Grindelia squarrosa) and others of like nature 

 there is nothing we can do more than to dig them up by hand, or 

 treat them with chemicals, which also will kill the grass around. 

 The process is slow but the areas affected are usually not large. 

 Walks and driveways can be kept clear by the aid of salt, kerosene, 

 arsenite of soda, or some of the various chemicals sold by seedsmen. 

 Much time and labor can be saved, if it be remembered that the 

 streets, roadsides and waste places are the natural storehouses for 

 the growth and propagation of weeds and that these places must 

 be kept clear, or at least the weeds must be kept from seeding in 

 them, if the yards, gardens and fields adjacent are to be free from 

 these pests. 



The Russian thistle, of which so much has been said and written, 

 does not appear to exhibit such dangerous characteristics in 

 this state. I have found it nowhere in any abundance except in 

 the Milk River and Yellowstone valleys, and there as well as in all 

 other places observed it is confined to the railway grades and 

 waste places about the towns. It makes no headway against the 

 native vegetation and has not \^et, in any r case noted, invaded 

 cultivated land. Nevertheless, its wide advertisement as a most 

 dangerous pest must be based upon its tendencv to invade grain- 

 fields and cultivated ground and it is comparatively little trouble 

 to prevent it from securing a footing in any locality, if taken 

 when it first appears and every plant be uprooted, piled and 

 burned. It is possible that it may yet prove a valuable forage 

 plant for the arid regions, and instead of a most dangerous, immi- 

 grant, it may prove a valuable addition to our native vegetation. 



The Scotch bull thistle is not nearly as dangerous as the dan- 

 delion and sheep-sorrel, the wild oats, the wild mustard, tumbling 

 mustard and the sunflower. It is very rare in the state, occurring 

 mostly about railway stations and towns, in no considerable 

 quantity except in the Flathead valley in the vicinit}- of Demers- 



