174 BOAKD OF AGRICULTURE. 



system of manuring is concerned, as well as the kind of 

 crops which have been previously raised upon them. 



2. The quality and relative quantity of the various essen- 

 tial articles of plant food which a satisfactory yield of the 

 contemplated crop requires. 



3. The degree of natural fitness of the plant to be raised, 

 to avail itself not only of the atmospheric plant food, but 

 also of the existing inherent amount of plant food in the soil 

 to be used for its production. The development of their 

 root and leaf system, as well as the shorter or longer period 

 of time required for their growth, deserves a most serious 

 consideration in this connection. 



Perennial plants are as a rule better qualified to benefit by 

 existing and inherent resources of plant food of the air and 

 the soil ; our best meadow grasses are perennials. 



A general system of high manuring pays, not infrequently, 

 for this reason in a less degree if applied to naturally good 

 grass lands, than if applied to other farm crops. The advice 

 quite frequently ooticed in the publications of writers on 

 agricultural topics, " Do not put your manure on your 

 grass lands as long as your ploughed lands are benefited 

 by it," is based on that observation. It ought to be acted 

 upon with an intelligent discrimination to avoid serious mis- 

 takes ; for, however applicable the stated advice may have 

 proven in the past, in case of meadows and farms in favored 

 localities, it is not safe to carry it out as a general rule. A 

 superior natural fitness of the soil for the production of 

 remunerative grass crops, without the temporary assistance 

 of some kind of manurial matter, is more an exception than 

 a common occurrence. 



The low average yield of a large proportion of our grass 

 lands proves the correctness of the previous statement. 



Under thfese circumstances it seems advisable to discrim- 

 inate between the better class of permanent grass lands 

 and the periodical grass lands, when discussing modes of 

 manuring, for they represent different conditions. 



The cultivation of one and the same crop year after year 

 upon the same land, without some system of a periodical 

 manuring, changes, gradually but surel}^ the composition of 

 the soil, and renders it sooner or later practically unfit for 



