13 



Bidens frondosa, L, Common Beggar Ticks. 

 Along roadsides and in waste places. 



Aiithrmis cofula. L. Mayweed. 



Common in dooryards, along roadsides, and in waste places on 

 rather hard soil, preferably clay or loam. Also troublesome in 

 Europe. (Thaer. :> and Ratxebnrgf, 1. i 



Achillea millefolium, L. Yarrow. 



In pool' and dry pastures, and along roadsides, [ts presence 

 is an indication that the soil is rather poor. The plant is wid 

 distributed across the continent of America, and also in 

 Europe. 



Chrysanthemum leucanthemriim, L. Daisy. 



N<»t common. In this region tmly a few localities are known; 

 One in La Crosse, which is now obliterated, and in several other 

 places a few straggling specimens. In eastern United States this 

 weed is ('specially troublesome, but in Wisconsin and Minnesota 

 it is rare and somewhat local. 



Tanacetum mlgare, L. Common Tansy. 



At one time largely cultivated as a garden plant, and uow 

 thoroughly naturalized. Along borders of fences aud roadside-. 

 This perennial is somewhat difficult to exterminate. 



Artemisia biennis, Willd. Biennial Wormwood. 



Common in waste places, dooryards and roadsides. Rapidly 

 spreading eastward. 



Arctium lappa, L. Burdock. 



Along fences, in waste places in rich soil. The plant persi>t^ 

 where once established, but does not spread as rapidly as many 

 of our other weeds, as most farmers cut the plant off, not allow- 

 ing it to mature its fruit. 



Ondcus arvensis, Hoffin. Canada Thistle. 



Fortunately this plant is uot as common here as it is in the 

 eastern states. Mr. J. S. Harris reports it from Trempealeau 

 Co.. Wis., and in Upham's catalogue of The Flora of Minnesota, 

 it is reported from Fillmore Co. In July, 1880, I found it in 

 the southern part of La Crosse Co., Wis., where it is said to have 

 est ablished itself some fifteen to twenty years ago. Prof. Beal 

 says: "Its course westward is likely to be checked by tin- 

 fact that it has usually failed to produce seeds on the prairii 

 But it spreads freely below ground. It is a common weed of 



fields in Europe. Linnaeus, in his Flora Lapponica, considered 

 it one of the greatest pests of the fields. (George Thurber, 3.) 



Thaer recommends deep plowing, several times in a season, 

 and after each plowing, to pull up the root stocks. Also that a 



