CULTIVATION. 91 



many kinds of soil quite sufficient. On light, sandy loam 

 soils in particular this system fully effects the desired results. 

 Cost of trench ploughing per acre. — About | of an acre can 

 be ploughed a depth of 12 to 14 inches per working day of 

 eight hours with a six-horse team, so that it takes about a 

 day and a half to plough 1 acre. Two drivers and one 

 ploughman are required, so that altogether this is equivalent 

 to ten days' work of one horse and four and a half days' 

 work of one man. Taking the cost of horse labour at 5s. 

 per day and wages at 2s. per day, the total cost for plough- 

 ing works out at — 



10 days' horse labour at - 5s. = £2 10 



4J days' wages 2s. = 9 



Total per acre £2 19 



In addition to this comes the expense of digging out and 

 turning over the soil of the furrows a further depth of 8 to 

 lO inches ; and, as one man can turn over about ^V o^ ^^ ^^re 

 a day, we must add twenty days' wages, together with, say, 

 Is. per acre for the wear and tear of the plough and gear, thus 

 giving a grand total of £5 per acre. 



Deep cultivation by horse labour alone can be carried out 

 in three ways only, viz., by 



(a) Two single ploughs, one behind the other ; 



(6) An ordinary plough, followed by a subsoil plough 

 (grubber) ; 



(c) A strongly built plough performing both tasks at 



once : 



though a depth of more than 20 inches can rarely be ex- 

 ceeded by this system. 



(a) The depth at which the two single ploughs can be 

 set depends on the nature of the ground, the looser the sur- 

 face soil the deeper the furrow cut by the first plough. The 

 proportionate depths cut by each— the width of both furrows 



