“As I said before,” continued the Doctor, “intelligent farmers seldom sell their straw, and they frequently purchase and consume on the farm nearly as much bran, shorts, etc., as is sent to market with the grain they sell. In the ‘Natural History of New York,’ it is stated that an acre of wheat in Western New York, of 30 bushels per acre, including straw, chaff, etc., removes from the soil 144 lbs. of mineral matter. Genesee wheat usually yields about 80 per cent. of flour. This flour contains only 0.7 per cent of mineral matter, while fine middlings contain 4 per cent; coarse middlings, 5½ per cent; shorts, 8 per cent, and bran 8½ per cent of mineral matter or ash. It follows from this, that out of the 144 lbs. of mineral matter in the crop of wheat, less than 10 lbs. is contained in the flour. The remaining 134 lbs. is found in the straw, chaff, bran, shorts, etc., which a good farmer is almost sure to feed out on his farm. But even if the farmer feeds out none of his wheat-bran, but sells it all with his wheat, the 30 bushels of wheat remove from the soil only 26 lbs. of mineral matter; and it would take more than five crops to remove as much mineral matter as one crop of wheat and straw contains. Allowing that half the ash of wheat is phosphoric acid, 30 bushels remove only 13 lbs. from the soil, and if the soil contains 4,000 lbs., it will take three hundred and seven crops, of 30 bushels each, to exhaust it.”
“That is to say,” said Charley, “if all the straw and chaff is retained on the farm, and is returned to the land without loss of phosphoric acid.”
“Yes,” said the Doctor, “and if all the bran and shorts, etc., were retained on the farm, it would take eight hundred crops to exhaust the soil of phosphoric acid; and it is admitted that of all the elements of plant-food, phosphoric acid is the one first to be exhausted from the soil.”
I have sold some timothy hay this winter, and propose to do so whenever the price suits. But some of my neighbors, who do not hesitate to sell their own hay, think I ought not to do so, because I “write for the papers”! It ought to satisfy them to know that I bring back 30 cwt. of bran for every ton of hay I sell. My rule is to sell nothing but wheat, barley, beans, potatoes, clover-seed, apples, wool, mutton, beef, pork, and butter. Everything else is consumed on the farm—corn, peas, oats, mustard, rape, mangels, clover, straw, stalks, etc. Let us make a rough estimate of how much is sold and how much retained on a hundred-acre farm, leaving out the potatoes, beans, and live-stock. We have say:
| Sold. | |
15 acres wheat, @ 40 bushels per acre | 18 tons |
5 acres barley, @ 50 bushels per acre | 6 ” |
15 acres clover seed, 4 bushels per acre | 1¾ ton. |
| Total sold | 25¾ tons. |
| Retained on the farm. | |
15 acres corn, @ 80 bushels per acre | 33½ tons. |
| Corn stalks from do. | 40 ” |
| 5 acres barley straw | 8 ” |
10 acres oats and peas, equal 80 bushels of oats | 12¾ ” |
| Straw from do. | 20 ” |
| 15 acres wheat-straw | 25 ” |
| 15 acres clover-hay | 25 ” |
| Clover-seed straw | 10 ” |
15 acres pasture and meadow, equal 40 tons hay | 40 ” |
5 acres mustard, equal 10 tons hay | 10 ” |
5 acres rape, equal 10 tons hay | 10 ” |
5 acres mangels, 25 tons per acre, equal to 3 tonsdry | 15 ” |
| Leaves from do. | 3 ” |
| Total retained on the farm | 252¼ tons. |
It would take a good many years to exhaust any ordinary soil by such a course of cropping. Except, perhaps, the sandy knolls, I think there is not an acre on my farm that would be exhausted in ten thousand years, and as some portions of the low alluvial soil will grow crops without manure, there will be an opportunity to give the poor, sandy knolls more than their share of plant-food. In this way, notwithstanding the fact that we sell produce and bring nothing back, I believe the whole farm will gradually increase in productiveness. The plant-food annually rendered available from the decomposition and disintegration of the inert organic and mineral matter in the soil, will be more than equal to that exported from the farm. If the soil becomes deficient in anything, it is likely that it will be in phosphates, and a little superphosphate or bone-dust might at any rate be profitably used on the rape, mustard, and turnips.
The point in good farming is to develop from the latent stores in the soil, and to accumulate enough available plant-food for the production of the largest possible yield of those crops which we sell. In other words, we want enough available plant-food in 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 easy matter to maintain this degree of fertility.
WHY OUR CROPS ARE 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. He did not seem to know that he had asked one of the most important questions in the whole range of agricultural science. It is a fact that a soil may contain enough plant-food to produce a thousand large crops, and yet the crops we obtain from it may be so poor as hardly to pay the cost of cultivation. The plant-food is there, but the plants cannot get at it. It is not in an available condition; it is not soluble. A case is quoted by Prof. Johnson, where a soil was analyzed, and found to contain to the depth of one foot 4,652 lbs. of nitrogen per acre, but only 63 lbs. of this was in an available condition. And this is equally true of phosphoric 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.