1869.] Agrimlture. 81 



leaves, dropped during the growth of the crop, and partly to an 

 abundance of roots, which are stronger and more numerous when 

 clover is grown for seed than when it is mown for hay, and also 

 when it is mown for hay than when it is fed off by sheep. The 

 nitrogenous matters in the clover-remains are, on their gradual 

 decay, finally transformed into nitrates, thus affording a continuous 

 source of food on which cereal crops especially delight to grow. 

 That the clover plant which robs the soil is, nevertheless, a fer- 

 tilizer of it, is illustrated in every example of a failing clover crop. 

 We remember seeing on the wheat field of a farm near Oxford 

 deficient strips stretching parallel across the land, which were 

 exjilained by the fact that the clover seed-barrow had here and 

 there missed; so that, whereas elsewhere the contents both of 

 subsoil and of atmosphere had, by a vigorous plant of clover, 

 been accumulated within the surface soil for the benefit of next 

 year's wheat crop, here the subsoil and the air, robbed by no clover 

 plant, had contributed nothing of their abundance, and the surface 

 soil was proportionally the worse. The same truth tells to some 

 extent on the comparison of a clover crop fed off with one allowed 

 to ripen ; for the development of roots, being checked when the 

 produce in a green state is fed off by sheep, in all probability then 

 leaves less nitrogenous matter in the soil than when clover is 

 allowed to get riper, and is mown for hay. And this, no doubt, 

 accounts for the observation made by practical men that, notwith- 

 standing the return of the produce in the sheep excrements, when 

 the clover is fed off green by sheep, wheat is generally stronger, 

 and yields better after clover mown for hay. We are quoting 

 Dr. Voelcker's words as well as his conclusions; and the whole 

 research appears to us a notable example of the way in which 

 the scientific man can most serviceably discuss farm practice for the 

 benefit of the farmer. 



Among the other papers in the current number of the ' English 

 Agricultural Society's Journal' is one by Messrs. Lawes and 

 Gilbert, on the " Home Produce, Imports, and Consumption of 

 AVheat," to which attention should be directed. It shows that 

 the average produce of small experimental plots of wheat upon the 

 Eothamsted Farm, imder the three several circumstances of " no 

 manure," " continuous dressings of farmyard dung," and " continued 

 dressings of various artificial manures," is a perfectly trustworthy 

 guide to the character of the crops generally throughout the 

 kingdom. It illustrates the fact that the growth of wheat has 

 of late years gradually diminished in this coantry, having fallen in 

 England from 3,400,000 acres in 1850 to 3,140,000 acres in 1867, 

 and in Scotland from 210,000 acres in 1854-57 to 110,000 in 

 1866-67. The average produce of this crop per acre is the 



VOL. VI. G 



