CHAPTER IV. 



TILLAGE. 



ALL operations upon the soil for its improvement and prepa- 

 ration for crops, may be included under the two heads of 

 tillage and stercology, or manuring. Tillage includes the 

 operations of draining, irrigation, paring and burning, rotation 

 of crops, fallow, extirpation of weeds and insects, ploughing, 

 ribbing, lapping, laying in beds, scarifying or grubbing, subsoil 

 ploughing, trenching, rolling, harrowing, hoeing, spading, &c. 



The objects of tillage are, 1. To loosen the soil and render 

 it permeable to air, water and the roots of plants. 2. To bring 

 up the subsoil and mix it with the surface. 3. To incorpo- 

 rate manures with the soil. 4. To allow free access of the 

 heat and light of the sun. 5. To pulverize the coarse and 

 compact portions. 6. To destroy weeds and insects. V. To 

 bury green crops designed for manures. 8. To render wet 

 soils dry and arable. .9. To supply a sufficiency of water to 

 dry soils. 10. Tojix movcable and light blowing soils. 11. To 

 clear the soil of roots ami stones. 12. To cover seeds with 

 soil "after sowing. t -. .5^%*$**" ^. 



The following operations are described by Colman, and are, 

 part of them, peculiar to the agriculture of Europe. 



Lapping consists in turning a furrow upon an unploughed 

 surface, so that when the field is finished, it is only half 

 ploughed. 



