Value of B of at ion 



377 



tends to depreciate. A rotation is useful because (1) it 

 provides different treatments for the land, the fault of 

 one year tending to be corrected by the management in 

 another year; (2) no one element of plant-food is ex- 

 hausted, the rotation tending to even up the demands; (3) 

 one crop leaves the land in good physical condition for 

 another; (4) it incorporates humus; (5) it destroys pests 

 and weeds; (6) it economizes labor; (7) when green 

 crops are turned under, available or digested plant-food is 

 incorporated with the soil, and nitrogen may be supplied. 

 The rotation of crops means, also, rotation in tillage, ma- 

 nuring and other treatment; and one of these may be 

 quite as important as the other. 



The reason for the resting " of land is hereby ex- 

 plained. It is not due to any need of recuperation in the 

 soil; but the good effects are the compound results of the 

 various benefits derived from tilling and rotation. Gar- 

 deners find that when soil becomes unproductive for a par- 

 ticular crop, a change to another crop may result in profit. 

 Soils that have l^cen long kept in market-gardens may be 

 benefited by seeding down for two or three years. When- 

 ever possible, attempts should Ije made to practice some 

 kind of a rotation in the market-garden area. Xow and 

 then, a part of the land may be laid down to clover for a 

 year or two until it recovers; this provides a form of 

 rotation and destroys insects and other organisms. 



2. THE DIRECT FERTILIZING OF THE LAND 



When the soil has been thoroughly fitted and improved 

 by all the foregoing means, a gardener may think of add- 

 ing plant-food. This plant-food may be supplied in a 



