390 REPORT OF THE COMMISSIONER OP AGRICULTCRE. 



periments were tried four years, and it was found by using the ordinary materials 

 known to everybody — nitrogen, potash, phosphoric acid, soda, magnesia, &c., in certain 

 forms, on soils that were absolutely sterile — plants could be produced perfect in all 

 their parts. That was the first point to be ascertained. Then to ascertaiu whether it 

 was needful for the farmer, with such soils as were within our reach, to use all the 

 elements of plant-nntrition, or whether the soil could be relied upon to provide certain 

 elements in sufficient abundance so that the farmer need not apply them. 



The experiments for four years seem to indicate that, with such soils as we were using, 

 gathering them on the college farm and for miles arouud, we need not apply to the 

 plant carbon in any form, state, or condition ; that that was provided by nature, and 

 always would be; that we need not feed any other organic element of nutrition but 

 nitrogen; that nature had not provided nitrogen in suiticient abundance, and that we 

 must apply it. Among the mineral elements of the soil it was found that we need only 

 use potash and phosphoric acid for our vegetable crops. There were one or two crops 

 where we decided that we should use not only potash aiid phosphoric acid, but mag- 

 nesia. Tobacco was one, oats was another, where we decided that it was necessary to 

 use magnesia; but for the ordinary crops on such soils, mark you, as we had to experi- 

 ment with, nitrogen, potash, and phosphoric 'Hcid were the only elements needed to be 

 used. And we also noticed that there was a remarkable relation existing between the 

 amount of crop produced and the quantity of the elements applied, which led to the 

 thought that, perhaps, with a certain quantity of nitrogen, potash, and phosphoric 

 acid given to the plant in the form of absolute food, a plant might be produced which 

 should contain as much nitrogen, potash, and phosphoric acid as we gave artiticially 

 to the plant wo cultivated. The results of opon-tield culture in 1873-74 seemed to sus- 

 tain that belief. The crops experimented with this year h.ive been corn, oats, hay, 

 beans, and the general garden-vegetables. 



First, I will take the experiments with corn. Two plots of land were taken this year, 

 BO far as we could determine, exactly alike in their quality. It was proposed to make, 

 over and above the natural product of the land, f^O bushels of corn to the acre. Ele- 

 ments containing as much nitrogen, potash, and phosphoric acid as would be contained 

 in .50 bushels of Indian corn, and the natural production of stalks for 50 bushels of 

 Indian corn, were therefore applied to the land. The result of that experiment was this: 

 The land without the manure yielded 25 bushels of corn, in round numbers ; the land 

 ■with the manure yielded 74 bushels. That is, the crop was one bushel less than the 

 statement, being 49 bushels instead of 50 bushels. 



For potatoes, two plots were taken. These two plots were the plots which were 

 planted with potatoes last year; the same plot without manure, the same plot with 

 manure, as in 1874. The statement was, the materials should be applied to make 100 

 bushels to the acre more than the natural production of the land. The land without 

 the manure made 128 bushels of potatoes to the acre ; the land with the manure made 

 279 bushels to the acre, or 51 bushels more than the statement. I will not stop to 

 answer the question why. 



Now I will give another experiment with corn, which will, perhaps, answer this 

 query, wliy the land yielded 51 bushels more of potatoes than the statement called for, 

 and I will answer another question which will by and by be asked me. » * • » 



In 1874 we were trying the experiment of growing corn according to this principle, 

 and we raised 104 bushels to the acre. In 1»75 we took the same plot and planted it 

 with corn again and did not give it any manure at all, the object being to see if the 

 laud was ruined or whether the manure of 1874 reached over into 1875 and afl'ected 

 advantageously the crop of 1875. On that i)lot this year we harvested 64 bushels to 

 the acre, without any maniire. The normal bearing of the land in 1874 — that is, on the 

 plot where the manure was applied— was 34 bushels to the acre. Now, then, (if it will 

 be accepted as such,) the manure of 1874, after producing its 104 bushels to the acre, 

 reached over into 1675 and gave us 29 bushels and a fraction of corn to the acre this 

 year as the effect of last year's manuring. 



Oats. — A presumptuous statement was made in relation to the growing of oats. It 

 was said that we would grow 50 bushels to the acre over and above the natural prod- 

 uct of the land. I ought to stop here and say to gentlemen present that we have got' 

 the poorest laud apparently — rocky, drift soil, discouraging in every way — on which 

 to try our experiments. The plot without manure gave us 15 bushels of oats to the acre. 

 The statement was 50 bushels more than the land would naturally produce. The yield 

 of the manured plot was G2 bushels to the acre, or 3 bushels less than the statement; 

 the land with manure producing 62 bushels, the land without manure producing 15 

 bushels. 



Hay. — Two plots of land were selected for the experiment with hay. The land had 

 not been plowed or manured for many years. The statement was that there should be 

 made on that land one ton of hay to the acre more than its natural product. The ele- 

 ments were accordingly applied by top-dressing in the spring, which was wrong, per- 

 haps. The yield of the uumanmed land for both crops was 1,700 pounds to the acre. 



