Talks on Manures / A Series of Familiar and Practical Talks Between the Author and the Deacon, the Doctor, and Other Neighbors, on the Whole Subject

by Joseph Harris

Our climate is very different from that of England. As a rule, we seldom have enough rain, from the time corn is planted until it is harvested, to more than saturate the ground on our upland soils. This year is an exception. On Sunday night, May 20, 1883, we had a northeast storm which continued three days. During these three days, from three to five inches of rain fell, and for the first time in many years, at this season, my underdrains discharged water to their full capacity. Had nitrate of soda been sown on bare land previous to this rain, much of it would, doubtless, have been lost by leaching. This, however, is an exceptional case. My underdrains usually do not commence to discharge water before the first of December, or continue later than the first of May. To guard against loss of nitrogen by leaching, therefore, we should aim to keep rich land occupied by some crop, during the winter and early spring, and the earlier the crop is sown in the autumn or late summer, the better, so that the roots will the more completely fill the ground and take up all the available nitrogen within their reach. I have said that this idea had modified my own practice. I grow a considerable quantity of garden vegetables, principally for seed. It is necessary to make the land very rich. The plan I have adopted to guard against the loss of nitrogen is this: As soon as the land is cleared of any crop, after it is too late to sow turnips, I sow it with rye at the rate of one and a half to two bushels per acre. On this rich land, especially on the moist low land, the rye makes a great growth during our warm autumn weather. The rye checks the growth of weeds, and furnishes a considerable amount of succulent food for sheep, during the autumn or in the spring. If not needed for food, it can be turned under in the spring for manure. It unquestionably prevents the loss of considerable nitric acid from leaching during the winter and early spring.

Buckwheat, or millet, is sometimes sown on such land for plowing under as manure, but as these crops are killed out by the winter, they cannot prevent the loss of nitric acid during the winter and spring months. It is only on unusually rich land that such precautions are particularly necessary. It has been thought that these experiments of Lawes and Gilbert afford a strong argument against the use of summer-fallows. I do not think so. A summer-fallow, in this country, is usually a piece of land which has been seeded down one, two, and sometimes three years, with red clover. The land is plowed in May or June, and occasionally in July, and is afterwards sown to winter wheat in September. The treatment of the summer-fallow varies in different localities and on different farms.

Sometimes the land is only plowed once. The clover, or sod, is plowed under deep and well, and the after-treatment consists in keeping the surface soil free from weeds, by the frequent use of the harrow, roller, cultivator or gang-plow. In other cases, especially on heavy clay land, the first plowing is done early in the spring, and when the sod is sufficiently rotted, the land is cross-plowed, and afterwards made fine and mellow by the use of the roller, harrow, and cultivator. Just before sowing the wheat, many good, old-fashioned farmers, plow the land again. But in this section, a summer-fallow, plowed two or three times during the summer, is becoming more and more rare every year.

Those farmers who summer-fallow at all, as a rule, plow their land but once, and content themselves with mere surface cultivation afterwards. It is undoubtedly true, also, that summer fallows of all kinds are by no means as common as formerly. This fact may be considered an argument against the use of summer-fallowing; but it is not conclusive in my mind. Patient waiting is not a characteristic of the age. We are inclined to take risks. We prefer to sow our land to oats, or barley, and run the chance of getting a good wheat crop after it, rather than to spend several months in cleaning and mellowing the land, simply to grow one crop of wheat.

It has always seemed to me entirely unnecessary to urge farmers not to summer-fallow. We all naturally prefer to see the land occupied by a good paying crop, rather than to spend time, money, and labor, in preparing it to produce a crop twelve or fifteen months afterwards. Yet some of the agricultural editors and many of the agricultural writers, seem to take delight in deriding the old-fashioned summer-fallow. The fact that Lawes and Gilbert in England find that, when land contains considerable nitric acid, the water which percolates through the soil to the underdrains beneath, contains more nitrate of lime when the land is not occupied by a crop, than when the roots of growing plants fill the soil, is deemed positive proof that summer-fallowing is a wasteful practice.

If we summer-fallowed for a spring crop, as I have sometimes done, it is quite probable that there would be a loss of nitrogen. But, as I have said before, it is very seldom that any water passes through the soil from the time we commence the summer-fallow until the wheat is sown in the autumn, or for many weeks afterwards. The nitrogen, which is converted into nitric acid by the agency of a good summer-fallow, is no more liable to be washed out of the soil after the field is sown to wheat in the autumn, than if we applied the nitrogen in the form of some readily available manure.

I still believe in summer fallows. If I had my life to live over again, I would certainly summer-fallow more than I have done. I have been an agricultural writer for one-third of a century, and have persistently advocated the more extended use of the summer-fallow. I have nothing to take back, unless it is what I have said in reference to “fall-fallowing.” Possibly this practice may result in loss, though I do not think so.

A good summer-fallow, on rather heavy clay land, if the conditions are otherwise favorable, is pretty sure to give us a good crop of wheat, and a good crop of clover and grass afterwards. Of course, a farmer who has nice, clean sandy soil, will not think of summer-fallowing it. Such soils are easily worked, and it is not a difficult matter to keep them clean without summer-fallowing. Such soils, however, seldom contain a large store of unavailable plant food, and instead of summer-fallowing, we had better manure. On such soils artificial manures are often very profitable, though barn-yard manure, or the droppings of animals feeding on the land, should be the prime basis of all attempts to maintain, or increase, the productiveness of such soils.

Since this book was first published, I do not know of any new facts in regard to the important question of, how best to manage and apply our barn-yard manure, so as to make it more immediately active and available. It is unquestionably true, that the same amount of nitrogen in barn-yard manure, will not produce so great an effect as its theoretical value would indicate. There can be no doubt, however, that the better we feed our animals, and the more carefully we save the liquids, the more valuable and active will be the manure.

The conversion of the inert nitrogen of manures and soils, into nitric acid, as already stated, is now known to be produced by a minute fungus. I hope it will be found that we can introduce this bacterium into our manure piles, in such a way as to greatly aid the conversion of inert nitrogen into nitrates.