I do not know that I make myself understood, though I would like to do so, because I am sure there is no point in scientific farming of greater importance. Mr. Geddes calls grass the “pivotal crop” of American agriculture. He deserves our thanks for the word and the idea connected with it. But I am inclined to think the pivot on which our agriculture stands and rotates, lies deeper than this. The grass crop creates nothing—developes nothing. The untilled and unmanured grass lands of Herkimer County, in this State, are no richer to-day than they were 50 years ago. The pastures of Cheshire, England, except those that have been top-dressed with bones, or other manures, are no more productive than they were centuries back. Grass alone will not make rich land. It is a good “savings bank.” It gathers up and saves plant-food from running to waste. It pays a good interest, and is a capital institution. But the real source of fertility must be looked for in the stores of plant-food lying dormant in the soil. Tillage, underdraining, and thorough cultivation, are the means by which we develop and render this plant-food available. Grass, clover, peas, or any other crop consumed on the farm, merely affords us the means of saving this plant-food and making it pay a good interest.
[ CHAPTER X.]
HOW TO MAKE MANURE.
If we have the necessary materials, it is not a difficult matter to make manure; in fact, the manure will make itself. We sometimes need to hasten the process, and to see that none of the fertilizing matter runs to waste. This is about all that we can do. We cannot create an atom of plant-food. It is ready formed to our hands; but we must know where to look for it, and how to get it in the easiest, cheapest, and best way, and how to save and use it. The science of manure-making is a profound study. It is intimately connected with nearly every branch of agriculture.
If weeds grow and decay on the land, they make manure. If we grow a crop of buckwheat, or spurry, or mustard, or rape, or clover, and mow it, and let it lie on the land, it makes manure; or if we plow it under, it forms manure; or if, after it is mown, we rake up the green crop, and put it into a heap, it will ferment, heat will be produced by the slow combustion of a portion of the carbonaceous and nitrogenous matter, and the result will be a mass of material, which we should all recognize as “manure.” If, instead of putting the crop into a heap and letting it ferment, we feed it to animals, the digestible carbonaceous and nitrogenous matter will be consumed to produce animal heat and to sustain the vital functions, and the refuse, or the solid and liquid droppings of the animals, will be manure.
If the crop rots on the ground, nothing is added to it. If it ferments, and gives out heat, in a heap, nothing is added to it. If it is passed through an animal, and produces heat, nothing is added to it.
I have heard people say a farmer could not make manure unless he kept animals. We might with as much truth say a farmer cannot make ashes unless he keeps stoves; and it would be just as sensible to take a lot of stoves into the woods to make ashes, as it is to keep a lot of animals merely to make manure. You can make the ashes by throwing the wood into a pile, and burning it; and you can make the manure by throwing the material out of which the manure is to be made into a pile, and letting it ferment. On a farm where neither food nor manure of any kind is purchased, the only way to make manure is to get it out of the land.
“From the land and from the atmosphere,” remarked the Doctor. “Plants get a large portion of the material of which they are composed from the atmosphere.”
“Yes,” I replied, “but it is principally carbonaceous matter, which is of little or no value as manure. A small amount of ammonia and nitric acid are also brought to the soil by rains and dews, and a freshly-stirred soil may also sometimes absorb more or less ammonia from the atmosphere; but while this is true, so far as making manure is concerned, we must look to the plant-food existing in the soil itself.