80 THE OLIVER PLOW BOOK 



A most vital reason why one should understand the 

 characteristics of weeds before attempting to eradicate 

 them is because plowing has a tendency to cultivate 

 certain types of weeds rather than kill them. Sorrel 

 and quack grass are two very common examples of this 

 type. All types of weeds that put forth a new sprout 

 from any root joint can be eradicated by plowing if the 

 ground plowed has the benefit of after treatment that 

 will keep the stems from becoming exposed to the sun- 

 light. The reason is the stems receive their nourish- 

 ment from the leaves which are exposed to the sunlight. 

 If it is possible to keep the top growth down so the leaves 

 cannot absorb the necessary light for sustenance the 

 plant naturally starves to death. 



Those surface root weeds which can be quickly killed 

 by cutting or burying in the ground do not cause much 

 worry. 



The three great rules to observe are first, prevent 

 weeds from going to seed; second, prevent weed seeds 

 from being sown on the farm; and third, prevent all 

 weeds from making a top growth. 



Farmers must not expect to keep their weeds down in 

 the field when they permit them to grow in fence corners, 

 along road sides, in pastures and other uncultivated 

 fields because these seeds are carried by the wind, birds, 

 water, and animals to all parts of the field where they 

 are ready for a new start and in very favorable condition 

 for germination and growth. 



Our scientists tell us that annual weeds, those which 

 grow from the seed each year, may be eradicated by any 

 method which starts germination and then destroys the 

 plant before it produces seed. Biennial weeds, or those 

 that live two years between the germinating of the seed 

 and the maturity of the plant, require an entirely dif- 



