96 THE SOIL OF THE FARM. 



with the soil. The depth to which the manure is turned 

 in should be regulated by the nature of the soil and of 

 the manure. On a clay soil it may be buried deeper with 

 advantage than on a sandy soil ; and a slow manure may 

 be buried deeper than a soluble and quick-acting manure. 

 It is not, however, good policy to bury any manure very 

 deeply. The rain in a drained soil will soon distribute it 

 throughout the mass to be fertilized ; but we must not 

 forget that the producing power of a soil is governed 

 more by the mass of its vegetable bed than by the meas- 

 ure of its superficies ; and where the subsoil is un ma- 

 nured the crop will often be underfed. One of the causes 

 of the failure of red clover is traced, we believe, to the 

 dying off of the roots when they penetrate beyond the 

 depth of available manure. Soluble manures, like nitrate 

 of soda and sulphate of ammonia, should be put on the 

 surface ; but undissolved phosphate, and even guano, is 

 best when just covered with the soil. Stiff clays are im- 

 mensely benefited by a good dressing of fresh farm-yard 

 manure plowed under to a tolerable depth. 



Top- dressings with artificial manures are chiefly to be 

 recommended for crops in the grassy stages of their 

 growth — wheat crops in spring, and grass lands at the 

 same season, and especially m wet seasons. In sucli sea- 

 sons one objection to this method of apjilying manure to 

 wheat is the tendency which it produces in the crop to 

 lodge. Salt will i)artly counteract this effect, and it does 

 so by strengthening and to some extent shortening tlie 

 straw ; but this is to counteract one of the principal ob- 

 jects of top-dressing. On clay soils, wliieh produce strong 

 straw, the tendency to lodge is less than on lighter soils. 

 In dry seasons, on the other hand, top-dressings of artifi- 

 cial manures are often inefficient, and the drier the cli- 

 mate the less likely are they to answer. But there are 

 doubtless circumstances when top-dressing may be profit- 

 able in any season — as on poor soils, and where the ma- 



