196 IOWA DEPARTMENT OF AGRICULTURE 
Marsh Elder. 
This weed is general in western Iowa along the Missouri where it 
largely takes the place of the Greater Ragweed. From the Missouri river 
it spreads eastward, reaching Cerro Gordo and Boone counties. Found 
in fields and along highways. 
Horse Nettle. 
This perennial weed is distinctly southern, common thoughout south- 
ern Iowa but reaching northward to the Minnesota line. Reported from 
fields and along highways. This weed is as difficult to exterminate as 
Canada Thistle. 
Sour or Curled Dock. 
Quite generally reported from all parts of the state, perhaps more 
common in eastern Iowa. Found along highways and in fields, especially 
meadows. Most frequently reported from Winneshiek, Pottawattamie, 
Montgomery, Fayette, Story and Cass counties. 
Smooth Dock. 
It is reported less frequently than Curled Dock. Less common along 
roadsides than Sour Dock. Most abundant in eastern Iowa. The coun- 
ties from which the weed is most frequently reported are Winneshiek, 
Fayette, Pottawattamie and Montgomery. 
Cowbane. 
This poisonous perennial weed is especially common in northern Iowa, 
from Ames northward to the Minnesota line and eastward to Benton and 
westward to Greene county. Occurs in low meadows and along high- 
ways. 
Dodders. 
Have been reported from a few widely scattered counties in the state 
on clover and alfalfa. 
Wild Oat. 
Not abundant in the state, only reported from a few counties in north- 
ern and western Iowa. 
Corn Cockle. 
Widely scattered in the state, especially where winter and summer 
wheat are cultivated. The absence of its occurrence in southern Iowa is 
because the reports from that part of the state are less complete, 
Jimson Weed. 
This weed is quite general in the state but less common along high- 
ways, commonly found near barns, and in waste places; more frequently 
reported from southern Iowa than elsewhere. 
Other Weeds Reported. 
Other weeds have been reported a varying number of times. Western 
Sunflower, Copimon Annual Sunflower, Wild Liqorice, Horseweed, Spotted 
Spurge, Goosefoot, Wild Hemp, Northern Nut Grass, European Morning 
Glory, Evening Catchfly, Yellow Hop Clover, Dandelion, Small Chickweed, 
Bristly Foxtail, Buffalo Bur, Tumbling Mustard, Sow Thistle, Five-Finger, 
Hedge Mustard, Russian Thistle, Green Foxtail, Meadow Sunflower, Black- 
