TRENCHING 29 



will elapse between the working and the seeding, the best 

 thing that can be done is to commence again and re-trench, 

 j in which process the two soils will regain their original 

 positions. The operation will then become more than ordi- 

 narily laborious, but the worker will have the satisfaction of 

 knowing that, as far as mechanical working is concerned, it 

 would be quite impossible for him to do more for his plants. 

 In true trenching the depth of moved soil should never 

 be less than 2 feet, and it ought to be 3 feet or a 

 little more. There are those who advocate the trenching 

 of soil to a depth of 5 or 6 feet, but one seldom sees 

 this put into practice, and it is almost certain that the 

 amount of good which the plants derive from it is quite 

 out of proportion to the labour entailed. The roots of 

 Sweet Peas seldom penetrate lower than 3 feet beneath 

 the surface, and, if they did, the probabilities are that their 

 lower extremities would not possess any great power of 

 feeding. The benefit, then, would be merely indirect 

 the root-run would be cooler and the soil would remain 

 moist longer in dry periods. Each grower must exercise 

 his own judgment as to the form of cultivation that is 

 likely to yield the best returns in his soil, and he can ex- 

 periment for two or three seasons until he makes himself 

 master of the problem. 



Time of Soil Working. Not only, however, has the 

 particular method of working to be considered, but the 



