98 FARMERS' INSTITUTES. 



development of subsequent crops lies at the foundation of scientific agricul- 

 ture." 



But some one may object that these laboratory experiments differ Avidely 

 from the conditions of plant growth in the field. "What matters it to us that 

 your laboratory plants gain one or one thousand times the nitrogen in the seed? 

 That is not the way we raise crops on the farm." 



There is force and apparent justice in this criticism. The conditions of 

 growth in the two cases are dissimilar and they must be in order to make the 

 experiment decisive. If you are testing some article of food for stock to 

 determine whether cattle will live and thrive on that single food, you do not 

 allow your steer to browse around and feed on everything in his way in addi- 

 tion to this fodder, but you shut him up to that article alone to see whether he 

 will thrive on this alone, and thus only you come to knoio what its food value 

 is for a given kind of stock. The same in wheat life. If we would know 

 whether a plant can derive its supply of nitrogen from a given source we must 

 grow that plant in such way as to shut it up to that single source of supply, 

 and not leave it free to obtain a supply from other quarters. Experimenters 

 in Agricultural Chemistry have hit upon no better way for settling these ques- 

 tions than such artificial mode of growth by exclusion of intercurrent means 

 of supply. 



A word about the value and meaning of these results. The first and most 

 important feature of soil exhaustion in ordinary farming is the want of an 

 adequate supply of active nitrogen. A full supply of this material means not 

 only an iucrease of vegetable growth, but crops of superior value, bushel for 

 bushel, and ton for ton. It means more hay, more wheat, more corn, and all of 

 these of better quality. It means more stock and in better condition. In a 

 word, it means prosperifi/ on the farm. Prosperity on the farm is quickly fol- 

 lowed by increased activity in mine and shop, the calling of hungry hordes of 

 unemployed workmen from the streets and alleys to farm and shop. It means 

 the revival of trade and the unloosening of the white wings of commerce. 

 These are some of the possible benefits to spring from a satisfactory solution of 

 this question of increased supply of available nitrogen. 



THE AGRICULTUEAL BAROMETER. 



Thirty years ago the average crop of wheat in this State was about thirteen 

 bushels to the acre ; it is now twenty-two bushels. Michigan thus stands at the 

 head of the class in the acreage product of wheat. I know of no single test 

 of the agricultural standing of a JState better than the average yield of wheat 

 to the acre where this crop is extensively sown. I call this average acreage 

 product of wheat the agricultural barometer to measure the level of farming 

 iu the United States. Measured by this standard Michigan has the highest 

 standing both by the United States census of 1880 and by the results reached by 

 our Secretary of State. What has brought Michigan agriculture to this high level? 

 Many causes combined : brains in farming, a good soil, improved machinery, 

 new varieties of wheat ; and in addition to all these the general cultivation of 

 clover, thereby securing increasing fertility instead of exhaustion of the soil by 

 cropping. Our farmers in general have recognized the value of clover pre- 

 ceding wheat We see some explanation of this value in the power of clover 

 to accumulate nitrogen from a source where wheat relatively fails, the clover 

 accumulation making good the deficiency of wheat in this regard. We also 

 find a reason why a supply of humus in the soil is beneficial to the clover. By 



