OJN MANURES. 



47 



It has however, been calculated by Dr. Coventry, the Pro- 

 fessor of Agriculture in the University of Edinburgh, that ara- 

 ble land of a medium degree of fertility and management, is 

 capable in ordinary years, of producing, in round numbers, per 

 imperial acre, about 28 bushels of wheat, 36 bushels of barley, 

 and 42 bushels of oats; and that the average quantity of straw 

 yielded by those crops will amount to 21 cwt. He then states 

 that, supposing this dry straw to be moistened and rotted, it 

 would thereby gain an addition to its weight equal to two- 

 thirds, or between three-lburths and two-thirds of its gross 

 weight — thus producing about 3j tons of manure : and admit- 

 ting that'some corn is consumed in the feed of horses, as well 

 as that the refuse of the grain, the chaff and light corn, besides 

 the straw, go ultimately to the dung-heap, ' one cannot reckon 

 the amount of the putrescent manure gained from an acre of 

 such produce at more than 4 tons.' But, judging by the like 

 proportion of moisture of different parcels produced by straw, 

 pulse, hay, or herbage of any sort, ' it is likely tliat a full pro- 

 duce of turnips, potatoes, or cabbages, would furnish even a 

 considerably greater weight,' By an experiment very care- 

 fully made by Mr. Dudgeon, of Prora, in East Lothian, it how- 

 ever appears that dry straw had only increased by absorption 

 from 300 to 719 stone, during a period of seven months ; which 

 is materially at variance with the Doctor's estimate of the 

 addition to its weight. It seems, however, from the statements 

 of several eminent farmers, that 1 ton of straw, when aug- 

 mented in weight by the dung and urine of turnip-fed stock, 

 will, if properly managed, produce about 4 tons of farm-yard 

 manure ;* but others, with more justice we think, are of opinion 

 that such a quantity can only be produced when the common 

 number of cattle on farms in the ordinary course of cultivation 

 are also fed in the usual way — upon hay, clover, and corn, as 

 well as turnips, besides being well littered with straw. Its 

 weight and value will of course be affected by its state of pre- 

 paration, as well as by the nature of the soil and its cultiva- 

 tion. Meadow land which produces If tons of hay per acre 

 has been calculated to give 6 2-5, or rather more than 6 tons 

 of manure per acre, and the fallow crops produce a large 



* Sinclair's Code of Agriculture, 3d edit., pp. 215, 440; Scottish Hus- 

 bandry, 2d edit., vol. i. p. 37'J, and jjassim. A liorwickshire farmer gives a 

 siuL'le cart-load of turnips per day to eight or ten cattle in the straw-yard. 

 He finds that, on an average of three years, from 2i to 3 acres of straw will 

 winter one of those oxen; and in this way each acre of straw will produce 

 about four double cart-loads of rotten dung, of from 30 to 35 cubic feet each. 

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