32 



HORTICULTURE 



LECT. II 



(1) Ploughing, (2) Digging, (3) Trenching, and 

 right and wrong methods of procedure in each case. 



Practical teaching on these subjects, can be better 

 conveyed by the aid of a few simple engravings than 

 in many words without them. 



In Fig. 2 (below) we have representations of 

 ploughing five or six inches deep, on the left side ; 

 digging, a foot deep, central ; and trenching two feet 

 deep on the right hand side of the illustration. In 



FIG. 2. SHALLOW AND DEEP WORKING. 

 1. Ploughing. 2. Digging. 3. Trenching. 



each case the relative differences in growth are in- 

 dicated by the character of the roots of the trees 

 and the varying thicknesses of the stems. 



Where the soil is shallow and a hard sole (a 1) 

 formed, the roots are of necessity confined to a very 

 small feeding ground, while if the soil is irony a 

 deposit may accumulate on the sole and be injurious. 

 In any event, the roots cannot penetrate the hard 

 medium, neither can the moisture of the lower strata 

 of the earth pass freely upwards to them in summer, 



