TILLAGE 



keep the condition of the soil friendly to plant life 

 in this respect. The wide variation in methods of 

 tillage is due to s the great differences in the tex- 

 ture and structure of soils, and to the habits of 

 plants, and skill in selection of methods is a meas- 

 ure of the intelligence used in farming. 



The Breaking-plow. Land containing enough 

 clay to give it an excellent soil inclines to become 

 firm. During the growth of a crop, when plant 

 roots fill the soil and prevent deep stirring, the 

 particles pack closely together, limiting the power 

 of the land to make fertility available. The 

 presence of organic matter counteracts, in part, 

 this packing tendency, but there are few soils 

 that remain permanently mellow. The breaking- 

 plow is used to loosen the soil, and to undo the 

 firming that has been taking place while plant roots 

 prevented deep tillage. At the same time the 

 plow may be used to bury organic matter be- 

 low the surface, affording a clean seed-bed. In 

 some soils it has value in bringing inert soil to the 

 surface, and in mixing the soil constituents. 



Types of Plows. The kind and condition of 

 the soil, and the character of the crop, determine 

 the type of plow to be used. A plow with a short 

 and quite straight moldboard does not bury ma- 



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