90 



MANUAL OF GARDENING 



method shown at a, he is obliged to break both edges at every 

 thrust of the tool; but when he cuts the slice diagonally, first 

 throAving his spade to the right and then to the left, as shown 

 at B, he cuts only one side and is able to make progress without 

 the expenditure of useless effort. These remarks will apply to 

 any spading of the land. 



In large areas, horses may be used to facilitate the work of 

 ditching. There are ditching plows and machines, which, 

 however, need not be discussed here; but three or four furrows 

 may be thrown out in either direction with a strong plow, and 

 a subsoil plow be run behind to break up the hard-pan, and 

 this may reduce the labor of digging as much as one-half. 

 When the excavating is completed, the bottom of the ditch is 

 evened up by means of a line or level, and the bed for the 

 tiles is prepared by the use of a goose-neck scoop, shown in 

 Fig. 79. It is very important that the outlets of drains be kept 

 free of weeds and litter. If the outlet is built up with mason 

 work, to hold the end of the tile intact, very much will be added 

 to the permanency of the drain. 



Trenching and suhsoiling. 



Although underdraining is the most important means of 

 increasing the depth of the soil, it is not always practicable 



81. Trenching with a spade. 



to lay drains through garden lands. In such cases, recourse 

 is had to very deep preparation of the land, either every year 

 or every two or three years. 



