SOILS. 71 



SECTION 2. DIFFERENT MODES OF IMPROVING SOILS. 



In regard to depth, soils vary materially, some being 

 not over eight or ten inches in depth of surface, others a 

 foot, while in deep alluvial valleys they are often two feet. 

 For orchard and garden purposes, a deep soil is quite 

 essential, to enable the roots to penetrate freely in search 

 of food, and to enable them to withstand the demands of 

 protracted drouths. Few soils in their ordinary condi- 

 tion of farm culture are, in this respect, suitable for trees. 

 Even where naturally deep and loamy, if the upper part 

 only (say to the depth of six inches, which is as deep as 

 most people plow) be in a friable condition, it cannot be 

 considered as in a proper state for the reception of trees, 

 for their roots cannot be confined to six inches of the sur- 

 face. Some means of loosening and deepening must be 

 resorted to, and what are they ? 



1. SUBSOIL PLOWING. 



This is the cheapest and best method, where a large 

 quantity of ground is to be prepared for extensive plant- 

 ing. The common plow goes first, and takes as deep a 

 furrow as practicable. The subsoiler follows in the same 

 furrow, and loosens, without turning up, the lower part 

 of the surface, and a part of the subsoil. Except in cases 

 where the subsoil is a very stiff clay, or a hard gravel, 

 and near the surface, the two plows can go to the depth 

 of eighteen or twenty inches. This is our mode of pre- 

 paring nursery grounds. If a single plowing in this way 

 does not accomplish the desired end, a second may be 

 given, going down still deeper. 



We had a piece of soil, the surface of which was about 

 a foot deep, of black vegetable mould, with a slight ad- 

 mixture of sand, resting on a stiff clay subsoil, which 

 prevented the water from passing off. In this condition 



