FIELD CROPS. 385 



is comparatively rare in Iowa, except northward and it is not known to be 

 weedy in tliat section of the State. ... In Utah the Bromus tectorum and 

 H. murinum- have become most troublesome weeds and rapidly spreading to 

 Colorado." 



"The Canadian thistle (Cirsium arvense) has made its way across the conti- 

 nent from Winnipeg west to Vancouver Island and Seattle. It has become 

 naturalized at numerous points, Winnipeg, Winnipeg Beach. Emerson, Moose 

 Jaw, Calgary, Portal, North Bend (B. C), Bremerton, Everett, Seattle, Wash- 

 ington. It has spread extensively in Manitoba, occurring in fields, meadows, 

 along roadsides and even occurring in woods. . . . They woolly thistle ( C canes- 

 cetis) indigenous to the country and to the South, to western Iowa, to the 

 Eocky Mountains in Colorado and Montana, is common east of Calgary. The 

 field thistle (C. discolor) though a common weed in Iowa and Minnesota, is 

 less common in the Red Elver Valley and only reaches across the border into 

 Manitoba." 



"The sow thistle (Solidago oleraceiis) occurs in Winnipeg, more frequent on 

 the Pacific coast, Seattle, and elsewhere; on the other hand, the perennial sow 

 thistle (<S'. arvensis) is abundant everywhere in }kIanitoba from Emerson to 

 Winnipeg and westward through the older settled portion of Manitoba." 



"The cat's-ear (Hypochceris radicata) which is naturalized from Europe 

 and a ballast weed along the northern Atlantic coast, does not occur in the 

 northern Mississippi Valley; it is one of the most common weeds in lawns and 

 in waste places from Oregon to Vancouver and the Vancouver Island." 



"The shepherd's purse (Capsella bursa-pastoris) is common from Winnipeg 

 to the coast, south to Texas, the Eocky Mountain region, and to the Atlantic 

 coast. It is more abundant in the North than in Iowa because of the cooler 

 climate." 



" Of the family Capparidaceae only 1 species occurs in the Canadian 

 region, namely Cleome integrifoUa. ... It is fairly common in Saskatchewan 

 and Alberta, less frequent in Manitoba. It is rare in British Columbia except 

 the more arid portions about Kamloops and Ashcroft." 



"The western pigweed (Monolepis nuttalliana) is common in Saskatchewan 

 and Manitoba, it is of more frequent occurrence in fields than the common 

 goosefoot and more abundant than the Russian thistle in the region. It has 

 not reached Iowa although found in Minnesota and reported from Missouri by 

 Eobinson and Fernald. It occurs in all of the provinces from Winnipeg to 

 British Columbia." 



"The common milkweed {Asclepias syriaca) occurs occasionally in southern 

 Manitoba and less so in the Saskatchewan, though it is one of the most common 

 weeds in Iowa and Minnesota. Of the family Urticacese one weed is common 

 from Kentucky north to Minnesota and Wisconsin and west to the Rockies, 

 and in the Great Basin country, namely the common hemp (Cannabis sativa) 

 which has largely spread from cultivated fields of the plant and its use as 

 a bird seed." 



"The wild licorice (Glycyrrhiza lepidota) is common everywhere on the 

 prairies of Minnesota to Winnipeg west to the provinces of Saskatchewan and 

 Alberta, but less frequent on the west slope, abundant in the Eockies to the 

 Great Basin. The 2 species of sweet clover (Mel Hot us alha and M. offl,cinalis) 

 are common in parts of Minnesota and on the west coast." 



"The buckhorn (Plantago larweolata) which has been widely distributed in 

 recent years with clover seed in Iowa, occurs throughout the northern Missis- 

 sippi Valley States and was observed in LaCrosse in 1S97. It was not observed 

 in the Northwest provinces, probably largely because clover is not a common 

 crop and the seed is generally distributed with clover seed." 



