28 TALKS ON MANURES. 



in the soil, and to accumulate enou;j;h available i)laut-foo(l for the 

 production of the largest possible yield of those crops which we 

 sell. In other words, we want tnough available plant-food ia the 

 soil to grow 40 bushels of wheat and 50 bushels of barley. I think 

 the farmer who raises 10 tons for every ton he sells, will .soon 

 reach this point, and when once reached, it is a comparatively 

 2agy matter to maintain this degree of fertility. 



WHY OUK CROPS .VRE SO POOR. 



" If the soil is so rich in plant-food," said the Deacon, " I again 

 ask, why are our crops so poor ? " 



The Deacon said this very quietly. lie did not seem to know 

 that he had asked one of the most important questions in the 

 whole range of agricultui-al science. It is a fact that a soil may 

 contain enough plant-food to produce a thousand large (;rops, and 

 yet the crops we obtain from it may be so poor as hardl}' to pay 

 the cost of cultivation. The i)lant-food is there, but the plants 

 cannot get at it. It ia not in an available condition ; it is not sol- 

 uble. A case is cpioted by Prof. Johnson, where a soil was an- 

 alyzed, and found to contain to the depth of one foot 4,652 lbs. of 

 nitrogen per acre, but only 03 lbs. of this was in an available con- 

 dition. And this is equallj'' true of phosplioric acid, potash, and 

 other elements of plant-food. No matter how much plant-food 

 there may be in the soil, the only portion that is of any immediate 

 value is the small amount that is annually available for the growth 

 of crops. 



HOW TO GET LARGER CROPS. 



" I am tired of i^o much talk about plant-food," said the Deacon ; 

 " what we want to know is how to make our land produce larger 

 crops of wheat, corn, oats, barley, potatoes, clover, and grass." 



This is precisely what I am trying to show. On my own farm, 

 the three leading objects are (1) to get the land drained, (2) to make 

 it clean and mellow, and (3) to get available nitrogen for the cereal 

 crops, iv'ter t'.ie first two objects are accomplished, the measure 

 of productiveness will be determined by the amount of available 

 nitrogen ii the soil. Ilon- to get available nitrogen, therefore, is 

 my chief and ultimate object in all the operations on the farm, 

 and it is here that science can help me. I know how to get nitro- 

 gen, but I want to get it in the cheapest way, and then to be sure 

 that I do not waste it. 



There is one fact fully estiiblislie 1 l)y repeited experiment and 

 general experience — that 80 lbs. of available nitrogen per acre, 



