“You do not,” said the Doctor, “draw the manure on to the heap with a cart, and dump it, as I have seen it done in England?”
I did so a few years ago, and might do so again if I was piling manure in the spring, to be kept over summer for use in the fall. The compression caused by drawing the cart over the manure, has a tendency to exclude the air and thus retard fermentation. In the winter there is certainly no necessity for resorting to any means for checking fermentation. In the spring or summer it may be well to compress the heap a little, but not more, I think, than can be done by the trampling of the workman in spreading the manure on the heap.
“You do not,” said the Doctor, “adopt the old-fashioned English plan of keeping your manure in a basin in the barn-yard, and yet I should think it has some advantages.”
“I practised it here,” said I, “for some years. I plowed and scraped a large hole or basin in the yard four or five feet deep, with a gradual slope at one end for convenience in drawing out the loads—the other sides being much steeper. I also made a tank at the bottom to hold the drainage, and had a pump in it to pump the liquid back on to the heap in dry weather. We threw or wheeled the manure from the stables and pig-pens into this basin, but I did not like the plan, for two reasons: (1,) the manure being spread over so large a surface froze during winter, and (2,) during the spring there was so much water in the basin that it checked fermentation.”
Now, instead of spreading it all over the basin, we commenced a small heap on one of the sloping sides of the basin; with a horse and cart we drew to this heap, just as winter set in, every bit of manure that could be found on the premises, and everything that would make manure. When got all together, it made a heap seven or eight feet wide, twenty feet long, and three or four feet high. We then laid planks on the heap, and every day, as the pig-pens, cow and horse stables were cleaned out, the manure was wheeled on to the heap and shaken out and spread about. The heap soon commenced to ferment, and when the cold weather set in, although the sides and some parts of the top froze a little, the inside kept quite warm. Little chimneys were formed in the heap, where the heat and steam escaped. Other parts of the heap would be covered with a thin crust of frozen manure. By taking a few forkfuls of the latter, and placing them on the top of the “chimneys,” they checked the escape of steam, and had a tendency to distribute the heat to other parts of the heap. In this way the fermentation became more general throughout all the mass, and not so violent at any one spot.
“But why be at all this trouble?”—For several reasons. First. It saves labor in the end. Two hours’ work, in winter, will save three hours’ work in the spring. And three hours’ work in the spring is worth more than four hours’ work in the winter. So that we save half the expense of handling the manure. 2d. When manure is allowed to lie scattered about over a large surface, it is liable to have much of its value washed out by the rain. In a compact heap of this kind, the rain or snow that falls on it is not more than the manure needs to keep it moist enough for fermentation. 3d. There is as much fascination in this fermenting heap of manure as there is in having money in a savings bank. One is continually trying to add to it. Many a cart-load or wheel-barrowful of material will be deposited that would otherwise be allowed to run to waste. 4th. The manure, if turned over in February or March, will be in capital order for applying to root crops; or if your hay and straw contains weed-seeds, the manure will be in good condition to spread as a top-dressing on grass-land early in the spring. This, I think, is better than keeping it in the yards all summer, and then drawing it out on the grass land in September. You gain six months’ or a year’s time. You get a splendid growth of rich grass, and the red-root seeds will germinate next September just as well as if the manure was drawn out at that time. If the manure is drawn out early in the spring, and spread out immediately, and then harrowed two or three times with a Thomas’ smoothing-harrow, there is no danger of its imparting a rank flavor to the grass. I know from repeated trials that when part of a pasture is top-dressed, cows and sheep will keep it much more closely cropped down than the part which has not been manured. The idea to the contrary originated from not spreading the manure evenly.
“But why ferment the manure at all? Why not draw it out fresh from the yards? Does fermentation increase the amount of plant-food in the manure?”—No. But it renders the plant-food in the manure more immediately available. It makes it more soluble. We ferment manure for the same reason that we decompose bone-dust or mineral phosphates with sulphuric acid, and convert them into superphosphate, or for the same reason that we grind our corn and cook the meal. These processes add nothing to the amount of plant-food in the bones or the nutriment in the corn. They only increase its availability. So in fermenting manure. When the liquid and solid excrements from well-fed animals, with the straw necessary to absorb the liquid, are placed in a heap, fermentation sets in and soon effects very important changes in the nature and composition of the materials. The insoluble woody fibre of the straw is decomposed and converted into humic and ulmic acids. These are insoluble; and when manure consists almost wholly of straw or corn stalks, there would be little gained by fermenting it. But when there is a good proportion of manure from well fed animals in the heap, carbonate of ammonia is formed from the nitrogenous compounds in the manure, and this ammonia unites with the humic and ulmic acids and forms humate and ulmate of ammonia. These ammoniacal salts are soluble in water—as the brown color of the drainings of a manure heap sufficiently indicates.
Properly fermented manure, therefore, of good quality, is a much more active and immediately useful fertilizer than fresh, unfermented manure. There need be no loss of ammonia from evaporation, and the manure is far less bulky, and costs far less labor to draw out and spread. The only loss that is likely to occur is from leaching, and this must be specially guarded against.