WEED DISSEMINATION 



95 



carried from place to place. Weed seeds are also widely 

 disseminated by birds and by streams. 



The seeds of the common milkweed are provided with 



Fig. 40. — Canada Thistle. 

 Stems as Well. 



It spreads by Seeds and by Underground 

 (Second Ohio Weed Manual.) 



a tuft of hairs which cause them to be carried along easily 

 by every gentle breeze. The common thistle, dandelion, 

 wild lettuce, and many others, have seeds which are pro- 

 vided with tiny parachutes by the aid of which they are 



