Rural School Leaflet 



935 



WEEDS 



J. L. Stone 



WEED has been defined as "a plant out of 

 place." Professor Roberts, as a result 

 of some experiments in the thickness 

 of seeding com, once said, " The worst 

 weed in corn is corn." A more com- 

 m-on conception, and one that is m.ore 

 satisfactory in this connection, is: "A 

 weed is a plant injurious to agriculture and to 

 horticulture." 



Weeds growing in crops cause great reduction 

 in yield and consequent loss to farmers. It has 

 been estimated that the loss from injury by weeds 

 in the United States is not far from $100,000,000 

 annually. 



Weeds affect crops injuriously in a number of 

 ways. They rob the crop of plant foods that other- 

 wise would be available for a more perfect develop- 

 m.ent of it. They often draw heavily on the soil 

 moisture, robbing the crop of its much-needed 

 supply. This 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 the normal de- 

 velopment of the crop. In many instances the 

 weeds actually crowd out part or all of the crop 

 plants. 

 Some weed seeds are difficult or impossible to separate from the cereal 

 grains, and the grains are depreciated in commercial value because of the 

 presence of these weed seeds. 



It is not the purpose of this lesson to go into the methods of eradicating 

 certain pernicious weeds after they are established in the soil, but to sug- 

 gest preventive measures regarding weeds in general. 



A given amount of effort will do more toward the suppression of weeds 

 if directed against the production of their seeds in the vicinity, or the 

 introduction of them from elsewhere, than it can do by fighting them after 



