52 WEEDS OF THE FARM AND GARDEN 



ing spring freshets. In addition to these plants, the pas- 

 tures throughout Iowa are, especially in the fall, troubled 

 with weeds such as goldenrod, the large yellow-flowered 

 goldenrod (Solidago rigida) being exceedingly common in 

 native pastures after the cattle have been running in them 

 all summer. Sometimes these pastures present a mass of 

 yellow. Frequently the 6". canadensis is found in similar 

 situations. In low-lying districts, especially in swampy 

 ground, the rose-flowered smartweed or shoestring 

 (Polygonum Muhlenbergii) is common. This persistent 

 perennial produces very long, thick, stout root stocks and 

 grows so thickly that grass does' not appear. Another 

 weed which occurs in our low, wild meadows is the this- 

 tle (Cirsium iowense), a biennial which makes very little 

 growth the first season, but the second season sends up 

 a large much-branched stalk and produces numerous 

 purple flowers. The allied bull thistle (C. lanceolatum) is 

 especially troublesome in pastures in the timber lot, fre- 

 quently growing in such large masses as to become de- 

 cidedly noxious. Canada thistle is common in the East 

 and Canada. Stock carefully feed around this plant, thus/ 

 permitting its seed to be sown broadcast in the field. It 

 is occasionally found in meadows also. The meadow- 

 sunflower (Helianthus grosseserratus) is common 

 throughout the northern states, in draws; the artichoke 

 (Helianthus tuberosus) also occasionally occurs. 



In the East, the ox-eye daisy (Chrysanthemum leucan- 

 themum), as yet rare in Iowa, is a pernicious weed in 

 meadows eastward. In the West the white weeds 

 (Erigeron ranwsus and E. annuus) take its place. In 

 the South, boneset (Eupatorium) and ironweed (Verno- 

 nia) are common. 



Another plant which has recently come into notice as 

 a troublesome weed is the rib plantain (Plantago lance- 

 olata), which has been brought into our meadows with 

 clover seed. It is much more common in the East than 



