68 CIVIC BIOLOGY 



the locality ? Discuss together as a class plans for bringing 

 them back to their native haunts. 



Weeds. Fighting weeds is often the most laborious and ex- 

 pensive part of gardening and of raising certain staple crops. 

 It was formerly said that weeds were the gardener's friends, 

 because they made necessary the frequent stirring of the soil, 

 which was considered beneficial to plant growth. Recent ex- 

 periments in raising corn have shown equal production with 

 absolutely none of this laborious stirring of the soil. In fact, 

 earlier experiments on the root system of the corn plant had 

 proved that the farmer actually, and very materially, reduced 

 his corn crop by deep cultivation. Other crops await similar 

 investigation. The results so far have been to rate the damage 

 caused by these " robber plants " at much higher figures than 

 formerly. If we could prepare the ground and plant our gardens 

 and fields and never see a weed, the labor and cost of produc- 

 tion from the soil might be reduced nearly, or quite, one half. 



Damage caused by weeds. Weeds are defined as " plants 

 which persist in growing where they are not wanted." No 

 less than seven hundred such plants are listed for the entire 

 United States. Make a list of weeds that are locally most 

 noxious. Weeds reduce yield of crops by crowding, and by 

 robbing the plants of water and food in the soil and of light 

 in the air. They injure seeds and flour, cause objectionable 

 flavors in milk, and poison stock. A recent estimate by the 

 Division of Farm Management of the United States Depart- 

 ment of Agriculture places the total annual damage of weeds 

 at 1500,000,000. What part of this yearly tax is imposed on 

 your own home, garden, or farm ? What is the annual damage 

 and cost of fighting weeds in your district, township, county, 

 or state ? 1 Can you propose a plan of cooperative work by 

 which this may be reduced ? 



1 Secure your state bulletins on weeds to assist in working out the prob- 

 lems suggested. Write also for the Weed Laws of your state. 



