118 PLANT LIFE ON TflE FARM. 



conditions than others. Thus spring wheat, barley, of 

 oats, may be made in a degree to supply the deficiencies 

 of the autumn sown wheat, and tares, beans, peas, 

 carrots, etc., etc., employed to compensate for the failure 

 of other crops. 



Manures. By the judicious use of suitable manures 

 at the right time, the farmer is also enabled in some de- 

 gree to provide for and counteract the effects of unpro- 

 pitious seasons. Farm-yard manure, for instance, not 

 only increases the quantity of grain and of straw, but 

 greatly improves the quality of the grain, as measured in 

 pounds per bushel ; and the same holds good of a mixed 

 mineral and nitrogenous manure. 



The time when nitrogenous manures can be most 

 beneficially applied is a matter of great consequence, 

 Messrs. Lawes and Gilbert having proved that the 

 nitrogen carried off the land in the drainage water, is 

 much greater when the manure is applied in the autumn 

 than when used in spring. Another illustration of the 

 use of manures of an opposite character to that just 

 cited, is afforded by the use of common salt (sodium 

 chloride) to check rank growth with its tendency to pro- 

 duce straw rather than grain. 



The varying effects of season, according to the nature 

 of the manure employed, suggest also that a variety of 

 manures should be used. In the Rothamsted experi- 

 ments, it has been shown that the seasons which proved 

 most propitious to the unmanured crops, and to those to 

 which only mineral manures were applied, were not 

 equally so for the crops to which nitrogenous manures 

 were applied; hence, says Sir J. B. Lawes/' the best season 

 for land in low condition is not the best for land in high 

 condition." 



The varying effects of manure may be illustrated by a 

 few figures taken from- the Rothamsted "memoranda" : 



