166 BOARD OF AGRICULTURE. 



same kind of constituents of the soil for their useful growth, 

 but also in different relative proportions in case of different 

 plants. This fact imposes upon us the task of regulating the 

 supply of the essential plant constituents. The successful 

 introduction of the trade in commercial fertilizers is a prac- 

 tical illustration of the relations of scientific methods of 

 inquiry to practical agriculture. In the light of our present 

 information, it appears but natural that a system of farming 

 which docs not provide in an economical way for a return in 

 an available form of the soil constituents carried off by the 

 crop raised, cannot otherwise but prove ultimately a finan- 

 cial fixilure. The less the variety of crops raised in succes- 

 sion upon the same lands, the more one-sided is usually the 

 exhaustion of the soil, and the sooner, as a rule, will be 

 noticed a decrease in the annual yield. 



A change from the beaten path of the older systems of 

 farm management only can reveal to us the extent of this 

 condition in the case of many of our so-called exhausted 

 grass lands. 



From a practical point of view, not less important than 

 the previously stated results of scientific methods of inquiry, 

 are the observations made regarding the botanical and phys- 

 iological characteristics of grasses. 



The more prominent species of grasses have been of late 

 more closely studied in that direction ; and some valuable 

 foreign varieties have been added to our home supply. 



The special adaptation of different species as well as of 

 difierent varieties of the same species to different kinds and 

 difterent conditions of soil has been investigated. 



The duration of their life ; their time of blooming ; the 

 special character of their root system, whether compact and 

 short, or loose and extensive ; their natural tendency of pro- 

 ducing mainly tall, blooming stems, with a limited leaf de- 

 velopment, or a liberal leaf growth with but a few blooming 

 stems ; and last, but not least, their chemical composition 

 and nutritive value in different stages of growth and in case 

 of different systems of cultivation and of manuring, have 

 been made more or less special subjects of scientific research. 

 The additional information gained in consequence of these 

 and similar labors cannot well be over estimated, as far as 



