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CHAPTER XI

MANURIAL VALUES OF FEEDING STUFFS

Fertility in Feeds.—When a farmer buys feed for his stock the fertility which is contained therein is often not taken into consideration, especially in the central or western States, where the supply of fertility in the soil, as a rule, has not as yet been depleted by continuous cropping. Farmers in the older sections of our country, and in the countries of the Old World, who pay out enormous sums of money annually for commercial fertilizers, are more likely to consider the manurial value of feeding stuffs. In addition to furnishing feed for farm animals, all plant materials supply valuable fertilizer ingredients (nitrogen and mineral matter) which largely go into the manure and aid in restoring the fertility of the farm land that has been lost through the removal of agricultural crops. Under otherwise similar conditions the feeds that furnish the largest quantities of fertilizing ingredients should, therefore, be selected. We understand by manurial value of feeds the value which these would have if applied directly as manure on the land. This value is figured on the basis of the amounts and cost of the three fertilizer constituents, nitrogen, phosphoric acid, and potash, which have definite and fairly constant market values. Table V in the Appendix shows that a ton of alfalfa hay, e.g., contains 44 pounds of nitrogen, 10 pounds of phosphoric acid, and 34 pounds of potash ; these amounts of fertilizer constituents would be worth, at a low valuation (15 cents per pound of nitrogen, 4 cents per pound of phosphoric acid and potash), $8.36 (Fig. 10).1

If a farmer buys a ton of alfalfa hay, he therefore receives, in addition to the energy for feeding purposes contained therein, an amount of fertilizer constituents which would cost $8.36 if bought in the form of commercial fertilizers. In the same way, the fertilizer value of Indian corn would be $5.64; oats, $6.63; wheat bran, $11.55; linseed meal, $18.75, and cotton-seed meal, $23.36.

These figures make up a large proportion of the market values of the feeds; a study of them will show that the most expensive feeds, which are all high-protein feeds, have, generally speaking, also the

* Present market prices vary considerably from the figures used in these calculations.

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highest manurial values. Where there is a choice between different feeding stuffs, the contents of valuable fertilizer ingredients in the feeds should receive careful consideration. By way of illustration we may bring together in a table some of the common feeding stuffs :

Fertilizer Ingredients of Some Common Feeds Contained in One Ton

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We note that among the coarse feeds the legumes are richer than the grasses, not only in nitrogen, but also in potash, and slightly so in phosphoric acid. Cottonseed meal, linseed meal, and gluten meal, among the concentrates, are all high in nitrogen, but, unlike the first two, gluten meal is greatly deficient in both phosphoric acid and potash. Indian corn is very low in all three fertilizer ingredients, and brewers' grains are low in phosphoric acid and potash, especially the latter. Feeds of high fertilizer values should, under otherwise similar conditions, be preferred to those of relatively low fertilizer value if they serve equally well the purpose in view. Indian corn is, therefore, other things being equal, worth less to the farmer than is wheat bran, and linseed meal and cottonseed meal are worth more than either.

Fertility Retained by Farm Animals.—The amounts of the fertilizer ingredients of feeding stuffs retained by farm animals in their bodies or made use of in their products will vary with different animals, and with the same animals at different periods of growth. The following table ? shows the proportions of nitrogen and ash constituents voided by animals or obtained in animal products, according to the English agricultural scientists, Lawes and Gilbert, of the Rothamsted Experiment Station :

'Warington, “ Chemistry of the Farm,” 21st edition, 1913, p. 214,

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Quantities of Nitrogen and Ash Constituents Voided by Animals or Obtained in

Animal Products

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We note that milch cows void in the total excrement about 75 per cent of the nitrogen contained in the feed and about 90 per cent of the ash constituents. Young growing animals give somewhat similar quantities, while fattening animals void about 90 per cent of nitrogen and 96 per cent of the ash materials in the liquid and solid excrement. Considering the relation between the different classes of farm animals on most stock farms, young and old, milkproducing and fattening animals, etc., we may assume that at least 80 per cent of the entire manurial value of the feeding stuffs fed on the farm will be voided in the solid or liquid manure of the animals and will contribute to maintain the fertility of the land when the manure is applied thereon. The direct value of feeding stuffs for fertilizer purposes is, therefore, obtained by taking 80 per cent of the total fertilizer value calculated from Table V in the Appendix.

When a farmer sells a ton of alfalfa hay, he sells fertilizer materials that if purchased in the form of common fertilizers would cost him over $8. He sells the amounts of fertilizers off his land in every ton of straw, hay, and other crops, as shown in the table. If he sells 2000 pounds of milk (232 gallons), $1.97 worth of fertility leaves the farm with it; with a ton of butter, 38 cents; with a ton of beef, $9.06; with a ton of pork, $5.93, etc. According to Burkett, a farmer selling hay sells, in the form of fertilizer value, one-half as much as he receives; if he sells pork, he receives twenty times as much for it as the value of the fertilizers contained in it; if milk, forty times, and if butter, one thousand times.

These figures show plainly that, so far as maintenance of the fertility of the land goes, it is a better plan for a farmer to sell

* Wisconsin Report 13, p. 270 et seq.

Feeding Farm Animals,” p. 311.

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animal products than grain or hay. The depletion of fertility from the farm is reduced to a minimum through the sale of these products.

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BUTTER

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NITROGEN PHOSPHORIC ACID POTASM MANURIAL VALUE PER TON
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Fig.10.–Manurial value of feeding stuffs (nitrogen valued at 15 cents per pound, phosphoric

acid and potash, 4 cents per pound).

QUESTIONS 1. Explain what is meant by the manurial values of feeding stuffs. 2. Name some feeds that are especially high in fertilizer ingredients; also

some that are low. 3. What percentage of nitrogen and of ash constituents are voided in the

total excrement by (a) milch cows; (b) fattening steers? 4. Why is it a poor practice to sell hay or straw from a farm? 5. What is the value of the fertility obtained in a ton of milk;, a ton of

pork; a ton of alfalfa hay?

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CHAPTER XII GREEN FORAGE AND HAY CROPS Farm animals depend on green feed for their sustenance for a considerable part of the year, the period varying according to climatic conditions, from about four months during the summer time in the North to nearly the entire year in the regions more favored in this respect, in the South and Southwest. During this time the stock, as a general rule, receive no feed but what they find growing in the pasture, on the plains or mountain ranges. It is only in sections where somewhat intensive systems of farming have been introduced that other feed is provided for the stock during this period, as in the case of dairy cows in late summer and fall. Both because of the length of time during the year when farm animals depend wholly or mainly on pasture grass for their feed, and because grazing is universal throughout the country at some time of the year, pasture grasses form a most important source of feed for our livestock.

I. PASTURES

Pastures.—We distinguish between natural and artificial pastures. The former are self-sown and consist largely of native grasses. These are the permanent pastures generally found in hilly or wooded regions in the northern States and in the western United States, where wild native grasses cover the wide plains and ranges.

With Spillman we may consider that the United States consists of six different agricultural sections, each one of which is characterized by the growth of special plants of agricultural value. These sections, with some of the main grasses and clovers grown in pastures and meadows in the different sections, are given below.

1. The Timothy Region (northeastern part of the United States, as far south as a line from Virginia to Kansas, and east of a line from Kansas to eastern North Dakota): Timothy mixed with red clover or pure seeding, red top, Kentucky blue grass, orchard grass, fescue grass.

2. The Cotton Belt: Cowpeas, Johnson grass, soybeans, Bermuda grass, crab grass, Japan and crimson clover.

Cyclopedia American Agriculture, vol. ii, p. 42. See also Farmers' Bul. 66, Meadows and Pastures.

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