The Book of Alfalfa: History, Cultivation and Merits / Its Uses as a Forage and Fertilizer

It is a fundamental principle of the best agriculture that every acre should be kept constantly at its highest productive capacity. In one sense the farm is a great machine for the production of food. All prosperity must originate on and emanate from the farm; the farmer is really the only original producer. The measure of the world’s material success must be the relative amount of the product of the farm. As lands decrease in fertility, the cost of living increases in direct proportion. As fertility decreases, land values decrease and rural population decreases. Already there are districts in America that are almost depopulated because of the barrenness of what was, but a short while ago, fertile land.

The fundamental principle of maintaining fertility is to restore to the land annually those chemical elements taken from it by the crops grown. A prominent importer of horses relates that he was once entertained on a great horse farm in France, whose owner told him that much of the farm had been in cultivation for over eight hundred years and was, he believed, as productive now as ever in its history.

Alfalfa ranks as the greatest fertilizing plant known to scientific agriculture. All cereal crops use large quantities of nitrogen. A field cropped for years in corn or wheat will come to have too little nitrogen for the production of a profitable crop. Alfalfa, as has already been stated, after the first few months of its life obtains its whole supply of nitrogen from the air; in fact, more than it really needs. As a soil improver it possesses at least five valuable properties:

1. It gathers nitrogen from the air for its own maintenance and a surplus that is constantly being added to the soil.

2. It is a deep feeder and its roots penetrate the earth to extraordinary depths, drawing toward the surface and utilizing moisture and valuable mineral elements that other crops would never reach, leaving the desirable elements there for future crops, of whatever kinds.

3. By capillarity, these roots and rootlets draw up moisture from below the surface until it modifies the very top soil, changing wonderfully the nature of the field. The analysis of a cubic foot of earth of a flourishing alfalfa field shows a marvelous change in moisture content since the sowing.

4. The mere mechanical effect of the extensive root system can scarcely be over-estimated. As soon as germination begins the plant starts its tiny roots downward on the search for moisture. Roots four feet long have been found on alfalfa but four months old; roots nine feet long have been found below alfalfa but nine months old. After the taproot reaches a few inches below the surface, it sends out smaller roots that have a lateral growth of but a few inches, when they too, take a downward course for moisture and for mineral elements needed for the growth above. These first smaller roots decay and others start out from the taproot lower down. These decay and still others start. The decaying roots add humus to the soil, and the openings left by them form a wonderful system of channels for the penetration of air and water into the soil. The erstwhile compact earth is honeycombed and air and water penetrate the graves of the dead roots until, when the alfalfa field is ready to be used for a different crop, the soil has been wonderfully changed not only in its chemical elements but in its physical character.

5. The regular deposit of alfalfa leaves, from the cuttings, under the best care, has been estimated at one-half ton or more per acre every year. As these leaves contain a great percentage of protein, it can readily be seen that they make a heavy contribution to the soil’s fertility.

VALUE OF STUBBLE AND ROOTS

When in his system of rotation the farmer is ready to plow up his alfalfa, he has another inestimable contribution to the land’s fertility in the stubble and roots. It is not recommended to plow under any considerable growth as a green manure, as the hay crop is too valuable. Its market value would buy more fertilizers than the same growth is worth for humus. After a field has stood for five or six years, the roots have added largely to the humus content. Prof. W. P. Headden of Colorado, estimated that the fertilizing value of the stubble and 6¹⁄₂ inches of roots plowed under is about $20 per acre, while the value of the stubble and entire root system is not less than $35 per acre.

The New Jersey station estimated that the amounts of plant food gathered by an acre of alfalfa in two years were equivalent in nitrogen to that contained in 3500 pounds of nitrate of soda; in phosphoric acid to that contained in 600 pounds of boneblack superphosphate, and in potash to the amount contained in 1200 pounds of muriate of potash, or equal to what would have cost $124.

EFFECTS ON SUCCEEDING CROPS

The Wyoming station, at Laramie, under direction of Prof. B. C. Buffum (Bul. No. 44) made some tests that proved the market fertilizing value of alfalfa. A plot of ground that had been in alfalfa for five years adjoined a plot of the same size that had been in varied crops, wheat, oats, potatoes, etc. After the alfalfa sod was broken the two plots were prepared together and planted crosswise to wheat, oats and potatoes, with half of each on the broken sod and half on the other plot with the following yields and gains:

Stating the results in another way, Prof. Buffum says: “The value of alfalfa harvested from one-half acre of land for five years was about $50 more than the cost of producing it.

“The value of potatoes and grain from an adjoining half-acre for five years was about $44 more than the cost of producing, at local prices.

“When the alfalfa half-acre was plowed and planted to wheat it produced $8 to $12 more value in wheat per acre than the land which had grown potatoes and grain before.

“When the alfalfa half-acre was plowed and planted to oats it produced $16 worth of grain more than land which had grown potatoes and grain before.

“When the alfalfa half-acre was plowed and planted to potatoes it gave $16 worth more of potatoes per acre than was obtained from land which had grown potatoes and grain before.

“By growing alfalfa the increase of yields and values were produced with absolutely no cost for fertilizing the land.”

This gain, it will be noted, cost nothing in the way of fertilization, as the alfalfa had every year been more profitable than the other crops. A Marion county, Kansas, manager of large estates reports that a field of wheat after alfalfa averaged forty bushels per acre while an adjoining field of equal original fertility averaged but fifteen bushels. These results have been duplicated in innumerable instances where alfalfa fields have been plowed and planted to other crops. A Colorado man who farms 1000 acres, with 200 acres of it in alfalfa, says he cannot afford not to plow his alfalfa after he has had from it four years’ crops; that it is necessary to maintain the general farm fertility and obtain big crops of corn, oats and potatoes. In the potato districts of Colorado alfalfa is used systematically as a rotation to maintain the yields and quality of their potatoes, both of which are so famous.

In the corn belt, which may be said to extend from the central meridian of Kansas to Pennsylvania, alfalfa used in rotation will do much to prevent the disgrace of raising an average of but twenty or twenty-five bushels of corn to the acre. And so in what were once famous wheat belts, alfalfa will restore the crop records, if properly used in a rotation.

ROTATION A NECESSITY

Some experiment station men insist that where alfalfa is allowed to stand for many years it will cease to have a fertilizing value; that alfalfa draws heavily on the potash and phosphoric acid in the soil, and will after, say, eight or ten years begin to deplete it of these important elements. Therefore they insist that alfalfa should not be allowed to stand for over six or eight years unless it is given an annual top-dressing of manure. They favor plowing up the alfalfa after about five years and cropping to corn or cotton.

Former Governor Hoard in speaking of the value of alfalfa as compared with that of clover in a crop rotation says that, “alfalfa having a much larger root development goes deeper down, thoroughly subsoils the ground, brings up phosphorus and potash from the lower strata, and leaves much more vegetable matter to decay and furnish humus. Nothing else we have ever tried equals alfalfa for putting the soil in good tilth.”

SPREADS THE BACTERIA OVER THE FARM

Men who are raising alfalfa for use in a regular rotation never leave it over six years; many prefer five, while others make it a rule to plow up their fields every four years; thus the bacteria becomes fixed in the soil of the whole farm. Such farmers use alfalfa as they formerly used clover, to restore fertility needed for profitable crops of grain, hay and forage.

The sod is hard to plow. It is well to do the breaking immediately after the season’s cutting, if possible; disk and harrow it several times and sow to rye for winter pasture, and plant to corn or cotton or potatoes in the spring. The winter’s freezing will help to put it in fine tilth. If it is desired to follow with wheat (not always advisable, however, on account of causing a too rank growth), the sod may be plowed after the year’s second mowing, disked and sowed to rye to prevent the soil from leaching.

Breaking up a well set alfalfa field is no trifling matter. It may be done with three heavy horses, but it is hard work for them, and they will not be able to break more than one acre a day. An authority says the best plan is to use five heavy horses—three in the lead and two on the end of the beam. They can go right along and plow two acres a day. Alfalfa roots are very tough and strong when the plants have attained full growth, and they give a jerky motion to the plow, which is severe on horses’ shoulders. A cast steel plow is the best to use and if it is tempered right a file can just cut it. It can be hammered out thin at the blacksmith’s shop when it becomes too thick to file easily. “The reason for filing, rather than using the hard, thin edge as in other plowing is that the edge needs to be rough as well as thin, or the roots will slip along the sloping edge of the share and not be cut.” It is important that the furrow turned shall not be wider than the plowshare will all the time cut clean, as any main roots that are left uncut will send up a more vigorous growth of stems than before, which, in another cultivated crop will be the same as weeds.