WEEDS 



J. L. Stone 

 Professor of Farm Practice, State College of Agriculture, Ithaca. 



One definition of a weed is " a plant out of place." Professor 

 Roberts, as a result of some experiments in the thickness of seed- 

 ing corn, once said, " The worst weed in corn is corn." A more 

 common conception and one that is more satisfactory in this con- 

 nection is that a weed " is a plant injnrions to agriculture and 

 horticulture." 



Weeds growing in crops cause great reduction in yield and 

 consequent loss to farmers. It has been estimated that the loss 

 in crop yield from injury by weeds in the United States is not 

 far from $100,000,000 annually. Also, the presence of weed 

 growths very materially increases the labor of giviug crops the 

 cultiA'ation necessary for their thrift. This increased labor cost 

 reaches a large figure. 



Weeds affect crops injuriously in a number of ways. They rob 

 the crop of plant foods that otherwise would be available for its 

 more perfect development. They often draw heavily upon the 

 soil moisture, robbing the crop of its much needed supply. This 

 is especially harmful in time of drought. The crowding of weeds 

 is especially harmful in some cases. The crop plants growing 

 among the weeds cannot develop leaves normally. In the leaves 

 the plant food is elaborated and from them the water in which 

 it was taken up is evaporated. If the leaves are dwarfed and 

 stunted for want of light and air, due to the crowding of weeds, 

 they cannot elaborate sufficient plant food for normal develop- 

 ment of the crop. In manv instances the weeds actuallv crowd 

 out part or all of the crop plants. 



Some weed seeds are difficult or impossible to separate from the 

 cereal gTains and the grains are depreciated in commercial value 

 on account of their presence. 



A given amount of effort will do more towards the suppression 

 of weeds if directed against the production of their seeds in the 



[1749] 



