100 FARMERS' INSTITUTES. 



Liebig says whatever a crop takes from a soil is the measure of its exhaus- 

 tion of the soil. If so, why does clover, which takes more nitrogen than any 

 other crop, yet enrich our soil? 



Mr. Ball: It takes it from the air. 



Dr. Kedzie: No, sir. It cannot get it from the air. Mr Gilbert says we 

 are consuming our capital of nitrogen in the soil and will soon exhaust the 

 supply. Why, then, do we now raise 22 bu. per acre, when a few years since we 

 raised 13? 



Mr. Ball: We are simply exhausting more rapidly our soil by better culture. 



Dr. Kedzie: Vegetable matter in changing into humus absorbs nitrogen from 

 the air and fixes it iu inert form and then the clover can use it. 



Mr. Ball: Can not plants absorb through their leaves the ammonia in the 

 rain ? 



Dr. Kedzie: That is possible, but the source is too small to be of moment. 

 Ammonia is so minute a constituent of the air that only about six pounds per 

 acre is brought down yearly by rains, or 8f pounds in both nitrates and am- 

 monia- not the one-fifth part of what is required for any crop. 



Mr, Peabody : I have sown much plaster and know nothing as to its value; 

 have tried it everywhere, but cannot be sure of its value, particularly in such 

 doses as 50 pounds per acre. I have noticed tliat burdocks grow in black soil 

 and that poor soil where they grow becomes good. Are they restorers to the 

 soil ? Is not a clover seed crop a robbery of the soil ? How are we to find the 

 value of commercial fertilizers ? I have seen the effects from plaster half a 

 mile away and yet know no means of estimating its cash value. 



Dr. Kedzie : How much plaster did you use to the acre ? 



Mr. Peabody : Fifty to 200 pounds. 



Dr. Kedzie : Fifty pounds is enough, because it is very sparingly soluble. Our 

 rainfall averages 32 inches per year and that amount cannot dissolve more than 

 50 pounds to the acre. Any more is inert. The College experiments showed 

 that plaster on corn increased the stalks but did not increase the grain at all 

 and this is the general conclusion. All leguminous crops under proper con- 

 ditions are benefited by plaster. Clover seed is rich in nitrogen and its removal 

 takes a good deal of nitrogen from the soil, but not as much as the crop makes 

 lip for. 



Mr. Peabody : Is salt a poison to plants ? 



Dr. Kedzie : A small amount of salt is good, but a large amount is fatal to 

 inland plants, though good for cabbage, kale, and other sea-growhig plants. I 

 would advise the extermiuation of burdocks. On light, porous soils having a 

 good proportion of vegetable matter, three to five bushels of salt per acre in the 

 spring, about the time of the last snow in April, is beneficial, but on clay and 

 other damp soils or those deficient in vegetable matter, salt is of no value. 



Mr. Fischer : A year or two ago a writer said that he improved the quality 

 and quantity of his wheat, increasing his yield iu five years from 25 bushels to 

 40 bushels per acre, by sowing clover in the spring with his wheat and then 

 after the wheat had been harvested, plowing the clover under. 



Dr. Kedzie : A field in clover two years and wheat every third year for -40 

 years improved right along. 



Mr. Fischer : My authority was Mr. George Geddes, and he said he sowed clo- 

 ver among the wheat in the spring and after harvest plowed the clover and 

 wheat stubble in and re-sowed wheat. 



Dr. Kedzie : No one disputes the value of clover. The valuable elements in 

 the plant are hardly touched by the animal n digesting them. The excrements 



