32 ARABLE LAND VERSUS GRASS 



(c) If we compare the amount of absolute food 

 (Ibs. of starch equivalent, see Table VIII, p. 94) grown 

 upon arable land and permanent grass, taking the 

 recorded average yields in Great Britain for the ten 

 years 1901-12, we obtain the following figures : 

 Barley, 1,716 Ib. ; oats, 1,576 Ib. ; roots and green 

 crops, 2,418 Ib. ; rotation grass, 840 Ib. ; permanent 

 grass, 645 Ib. A rotation of three years of grain crops, 

 one of roots and one of seeds, would produce a yearly 

 average of 1,653 lb- f starch equivalent against 

 645 Ib. from the permanent grass ; and a Wiltshire 

 rotation of two years of root and green crops followed 

 by two straw crops would produce annually 2,032 Ib. 

 of starch equivalent. Thus the arable land of the 

 country is at present producing from 2 J to 3 times as 

 much cattle food per acre as the permanent grass. 



Mr. T. H. Middleton (Journal Board Agriculture, 

 XXII, 1915, p. 520) sets out certain comparisons of the 

 yield from arable and grass land. On grazing land 

 the live weight increase per acre varies from 330 Ib. 

 on exceptional pasture, to 211 Ib. on medium grass 

 manured and to as little as 50 Ib. on really poor grass. 

 The milk yields vary from 260 to 190 gallons per acre. 

 Mr. Middleton's estimate of the produce of one acre of 

 arable land is 160 Ib. of live weight increase, together 

 with 315 Ib. of flour, 448 Ib. of potatoes, and 494 Ib. of 

 beer. 



From all the evidence we may conclude that the 

 crops from land under the plough, when used for 

 feeding cattle will produce of either meat or milk more 

 than twice as much as the same land will yield when 

 under grass, though as a rule 'part of these crops are 



