102 A MANUAL OF FORESTRY. 



and of the winter rains. In the following spring the 

 soil should again be worked, either with plough, spade, 

 or hoe, and harrowed so as to divide it finely. The nur- 

 sery operations can then be commenced, or the ground, 

 after manuring, be used during one season for the culti- 

 vation of a field crop, such as turnips, mangold-wurzel, 

 or potatoes, so that the additional cultivation may 

 produce a further division of the soil. After the 

 removal of the crop, the ground is ploughed and 

 left fallow over a second winter, when it should be 

 quite ready to serve as a nursery. 



h. Manuring. 



On good soil, plants can be raised for a number of 

 years without manuring, but sooner or later this becomes 

 necessary. Although the demands on the soil of a grow- 

 ing crop of trees are comparatively small, yet, through 

 the uninterrupted growing and removal of seedlings, 

 considerable quantities of various substances are taken 

 out of it, which must be replaced. At the same time 

 our knowledge as to the kinds and quantity of materials 

 which must be supplied to the soil is as yet deficient. 



Manuring, or amelioration generally, has for its object 

 to improve not only the chemical composition, but also 

 the physical qualities of the soil. If, at the outset, the 

 soil should not be of the proper consistency, it must be 

 improved by the admixture of sand to a stiff soil, 

 and by that of clay or loam to an excessively loose and 

 light soil. At the same time, and at any rate after a 

 few years, the soil can be specially manured by bringing 

 into it stable manure, guano, bone-dust, nitrates, phos- 



