18 WEED FLORA OF IOWA 



Extermination. — It is not generally recognized, but it is prob- 

 ably true, that more money is spent in the extermination of fox- 

 tails than of any other class of weeds we have in the state of Iowa, 

 yet they are all easily destroyed. One of the best and most effective 

 methods of destroying the foxtail is by plowing the small grain 

 field as soon as the grain is removed. If this is not done a large 

 amount of seed is produced. After this plowing in the fall the 

 field should be disked and harrowed in the spring and then planted 

 to corn. The com should be cultivated as frequently as possible, 

 at least four or five times. This method should prove effective for 

 the destruction of foxtail and pigeon grass. 



riG 8. Pigeon Grass (Setaria glauca) ■ a, spikelet showing the second glume, 



h! wv' r7>,"°S "* *^' flowering glume and bristles; b, spikelet showing 

 the back of the first and third glumes. 



(U. S. Dept. Agr.) 



