INTRODUCTORY 



19 



tunity for the weeds to increase. A thorough summer-fallow 

 would do much to bring the weeds under control, but this is 

 not always convenient. Seeding to grass and cutting the hay 

 crop early would prevent most kinds of weeds from ripening 

 more than a relatively small number of seeds, and the number 

 of vital weed seeds in the sub-surface soil would rapidly decrease 

 from year to year. If perennial weeds are also prevalent, it 

 would be well to pasture with sheep and mow the roughage 

 closely each year, before the spring growth has formed seeds. 



FARM IMPLEMENTS TO DESTROY WEEDS. 



The best time to destroy weeds is within two or three days 

 after the first pair of leaves has formed on the seedling plant. 

 In friable soils the "weeder" is a useful implement for that 

 purpose. The "tilting" harrow is also satisfactory for com- 

 paratively loose soils and is preferred as a weed destroyer on 

 firm or clayey land. Weeds are irregular in time of germina- 

 tion; consequently it is necessary to apply the weeder or harrow 

 frequently throughout the growing season. Fields of potatoes, 

 corn and cereal grains, when sown with a drill, may advan- 

 tageously be treated with these weed destroyers once or twice 

 before the crop distinctly shows above ground, and again, with 

 corn and ordinary grain crops, when the plants are three to six 



THE WEEDER 



