Talks on Manures Part 7

The manurial value of roots varies from 80 cents a ton for carrots, to $1.07 for mangel-wurzel, and $1.14 for parsnips.

I am very anxious that there should be no misapprehension as to the meaning of these figures. I am sure they are well worth the careful study of every intelligent farmer. Mr. Lawes has been engaged in making experiments for over thirty years. There is no man more competent to speak with authority on such a subject. The figures showing the money value of the manure made from the different foods, are based on the amount of nitrogen, phosphoric acid, and potash, which they contain. Mr.

Lawes has been buying and using artificial manures for many years, and is quite competent to form a correct conclusion as to the cheapest sources of obtaining nitrogen, phosphoric acid, and potash. He has certainly not overestimated their _cost_. They can not be bought at lower rates, either in England or America. But of course it does not follow from this that these manures are worth to the farmer the price charged for them; that is a matter depending on many conditions. All that can be said is, that if you are going to buy commercial manures, you will have to pay at least as much for the nitrogen, phosphoric acid, and potash, as the price fixed upon by Mr. Lawes. And you should recollect that there are other ingredients in the manure obtained from the food of animals, which are not estimated as of any value in the table. For instance, there is a large amount of carbonaceous matter in the manure of animals, which, for some crops, is not without value, but which is not here taken into account.

Viewed from a farmer's stand-point, the table of money values must be taken only in a comparative sense. It is not claimed that the manure from a ton of wheat-straw is worth $2.68. This may, or may not, be the case. But _if_ the manure from a ton of wheat-straw is worth $2.08, _then_ the manure from a ton of pea-straw is worth $3.74, and the manure from a ton of corn-meal is worth $6.65, and the manure from a ton of clover-hay is worth $9.64, and the manure from a ton of wheat-bran is worth $14.59. _If_ the manure from a ton of corn meal is _not_ worth $6.65, then the manure from a ton of bran is not worth $14.59. If the manure from the ton of corn is worth _more_ than $6.65, then the manure from a ton of bran is worth _more_ than $14.59. There need be no doubt on this point.

Settle in your own mind what the manure from a ton of any one of the foods mentioned is worth on your farm, and you can easily calculate what the manure is worth from all the others. If you say that the manure from a ton of wheat-straw is worth $1.34, then the manure from a ton of Indian corn is worth $3.33, and the manure from a ton of bran is worth $7.30, and the manure from a ton of clover-hay is worth $4.82.

In this section, however, few good farmers are willing to sell straw, though they can get from $8.00 to $10.00 per ton for it. They think it must be consumed on the farm, or used for bedding, or their land will run down. I do not say they are wrong, but I do say, that if a ton of straw is worth $2.68 for manure alone, then a ton of clover-hay is worth $9.64 for manure alone. This may be accepted as a general truth, and one which a farmer can act upon. And so, too, in regard to the value of corn-meal, bran, and all the other articles given in the table.

There is another point of great importance which should be mentioned in this connection. The nitrogen in the better cla.s.s of foods is worth more for manure than the nitrogen in straw, corn-stalks, and other coa.r.s.e fodder. Nearly all the nitrogen in grain, and other rich foods, is digested by the animals, and is voided in solution in the urine. In other words, the nitrogen in the manure is in an active and available condition. On the other hand, only about half the nitrogen in the coa.r.s.e fodders and straw is digestible. The other half pa.s.ses off in a crude and comparatively unavailable condition, in the solid excrement. In estimating the value of the manure from a ton of food, these facts should be remembered.

I have said that if the manure from a ton of straw is worth $2.68, the manure from a ton of corn is worth $6.65; but I will not reverse the proposition, and say that if the manure from a ton of corn is worth $6.65, the manure from a ton of straw is worth $2.68. The manure from the grain is nearly all in an available condition, while that from the straw is not. A pound of nitrogen in rich manure is worth more than a pound of nitrogen in poor manure. This is another reason why we should try to make rich manure.

CHAPTER XIII.

HORSE MANURE AND FARM-YARD MANURE.

The manure from horses is generally considered richer and better than that from cows. This is not always the case, though it is probably so as a rule. There are three princ.i.p.al reasons for this. 1st. The horse is usually fed more grain and hay than the cow. In other words, the food of the horse is usually richer in the valuable elements of plant-food than the ordinary food of the cow. 2d. The milk of the cow abstracts considerable nitrogen, phosphoric acid, etc., from the food, and to this extent there is less of these valuable substances in the excrements. 3d.

The excrements of the cow contain much more water than those of the horse. And consequently a ton of cow-dung, other things being equal, would not contain as much actual manure as a ton of horse-dung.

Boussingault, who is eminently trustworthy, gives us the following interesting facts:

A horse consumed in 24 hours, 20 lbs. of hay, 6 lbs. of oats, and 43 lbs. of water, and voided during the same period, 3 lbs. 7 ozs. of urine, and 38 lbs. 2 ozs. of solid excrements.

The solid excrements contained 23 lbs. of water, and the urine 2 lbs. 6 ozs. of water.

According to this, a horse, eating 20 lbs. of hay, and 6 lbs. of oats, per day, voids in a year nearly seven tons of solid excrements, and 1,255 lbs. of urine.

It would seem that there must have been some mistake in collecting the urine, or what was probably the case, that some of it must have been absorbed by the dung; for 3 pints of urine per day is certainly much less than is usually voided by a horse.

Stockard gives the amount of urine voided by a horse in a year at 3,000 lbs.; a cow, 8,000 lbs.; sheep, 380 lbs.; pig, 1,200 lbs.

Dr. Vlcker, at the Royal Agricultural College, at Cirencester, England, made some valuable investigations in regard to the composition of farm-yard manure, and the changes which take place during fermentation.

The manure was composed of horse, cow, and pig-dung, mixed with the straw used for bedding in the stalls, pig-pens, sheds, etc.

On the 3d of November, 1854, a sample of what Dr. Vlcker calls "Fresh Long Dung," was taken from the "manure-pit" for a.n.a.lysis. It had lain in the pit or heap about 14 days.

The following is the result of the a.n.a.lysis:

Fresh Farm-Yard Manure.

Half A Ton, Or 1,000 Lbs.

Water 661.7 lbs.

Organic matter 282.4 "

Ash 55.9 "

------------- 1,000.0 lbs.

Nitrogen 6.43 "

"Before you go any farther," said the Deacon, "let me understand what these figures mean? Do you mean that a ton of manure contains only 12 lbs. of nitrogen, and 111 lbs. of ash, and that all the rest is carbonaceous matter and water, of little or no value?" --"That is it precisely, Deacon," said I, "and furthermore, a large part of the ash has very little fertilizing value, as seen from the following:

Detailed Composition of the Ash of Fresh Barn-Yard Manure.

Soluble silica 21.59 Insoluble silicious matter (sand) 10.04 Phosphate of lime 5.35 Oxide of iron, alumina, with phosphate 8.47 Containing phosphoric acid 3.18 Lime 21.31 Magnesia 2.76 Potash 12.04 Soda 1.30 Chloride of sodium 0.54 Sulphuric acid 1.49 Carbonic acid and loss 15.11 ------ 100.00

Nitrogen, phosphoric acid, and potash, are the most valuable ingredients in manure. It will be seen that a ton of fresh barn-yard manure, of probably good average quality, contains:

Nitrogen 12 lbs.

Phosphoric acid 6 "

Potash 13 "

I do not say that these are the only ingredients of any value in a ton of manure. Nearly all the other ingredients are indispensable to the growth of plants, and if we should use manures containing nothing but nitrogen, phosphoric acid, and potash, the time would come when the crops would fail, from lack of a sufficient quant.i.ty of, perhaps, magnesia, or lime, sulphuric acid, or soluble silica, or iron. But it is not necessary to make provision for such a contingency. It would be a very exceptional case. Farmers who depend mainly on barn-yard manure, or on plowing under green crops for keeping up the fertility of the land, may safely calculate that the value of the manure is in proportion to the amount of nitrogen, phosphoric acid, and potash, it contains.

We draw out a ton of fresh manure and spread it on the land, therefore, in order to furnish the growing crops with 12 lbs. of nitrogen, 6 lbs.

of phosphoric acid, and 13 lbs. of potash. Less than 33 lbs. in all!

We cannot dispense with farm-yard manure. We can seldom buy nitrogen, phosphoric acid, and potash, as cheaply as we can get them in home-made manures. But we should clearly understand the fact that we draw out 2,000 lbs. of matter in order to get 33 lbs. of these fertilizing ingredients. We should _try to make richer manure_. A ton of manure containing 60 lbs. of nitrogen, phosphoric acid, and potash, costs no more to draw out and spread, than a ton containing only 30 lbs., and it would be worth nearly or quite double the money.

How to make richer manure we will not discuss at this time. It is a question of food. But it is worth while to enquire if we can not take such manure as we have, and reduce its weight and bulk without losing any of its nitrogen, phosphoric acid, and potash.

CHAPTER XIV.

FERMENTING MANURE.

Dr. Vlcker placed 2,838 lbs. of fresh mixed manure in a heap Nov. 3, 1854, and the next spring, April 30, it weighed 2,026 lbs., a shrinkage in weight of 28.6 per cent. In other words 100 tons of such manure would be reduced to less than 71 tons.

The heap was weighed again, August 23d, and contained 1,994 lbs. It was again weighed Nov. 15, and contained 1,974 lbs.

The following table shows the composition of the heap when first put up, and also at the three subsequent periods:

Table Showing Composition of the Whole Heap; Fresh Farm-Yard Manure (No. I.) Exposed--Expressed in Lbs.

----------------------------+---------+---------+---------+--------- When put April 30, Aug. 23, Nov. 15, up, Nov. 1855. 1855. 1855.

3, 1854. ----------------------------+---------+---------+---------+--------- Weight of manure in lbs. 2,838 2,026 1,994 1,974 Amt. of water in the manure 1,877.9 1,336.1 1,505.3 1,466.5 Amt. of dry matter in the manure 960.1 689.9 488.7 507.5 Consisting of-- Soluble organic matter { 70.38 86.51 58.83 54.04 Soluble mineral matter { 43.71 57.88 39.16 36.89 Insoluble organic matter { 731.07 389.74 243.22 214.92 Insoluble mineral matter { 114.92 155.77 147.49 201.65 -------- -------- -------- -------- 960.1 689.9 488.7 507.5 Containing nitrogen 4.22 6.07 3.76 3.65 Equal to ammonia 5.12 7.37 4.56 4.36 Containing nitrogen 14.01 12.07 9.38 9.38 Equal to ammonia 17.02 14.65 11.40 11.39 -------- -------- -------- -------- Total amount of nitrogen in manure 18.23 18.14 13.14 13.03 Equal to ammonia 22.14 22.02 15.96 15.75 The manure contains ammonia in free state .96 .15 .20 .11 The manure contains ammonia in form of salts, easily decomposed by quicklime 2.49 1.71 .75 .80 Total amount of organic matters 801.45 476.25 302.05 268.96 Total amount of mineral matters 158.15 213.65 186.65 238.54 ----------------------------+---------+---------+---------+---------

"It will be remarked," says Dr. Vlcker, "that in the first experimental period, the fermentation of the dung, as might have been expected, proceeded most rapidly, but that, notwithstanding, very little nitrogen was dissipated in the form of volatile ammonia; and that on the whole, the loss which the manure sustained was inconsiderable when compared with the enormous waste to which it was subject in the subsequent warmer and more rainy seasons of the year. Thus we find at the end of April very nearly the same amount of nitrogen which is contained in the fresh; whereas, at the end of August, 27.9 per cent of the total nitrogen, or nearly one-third of the nitrogen in the manure, has been wasted in one way or the other.

"It is worthy of observation," continues Dr. Vlcker, "that, during a well-regulated fermentation of dung, the loss in intrinsically valuable const.i.tuents is inconsiderable, and that in such a preparatory process the _efficacy of the manure becomes greatly enhanced_. For certain purposes fresh dung can never take the place of well-rotted dung. * *

The farmer will, therefore, always be compelled to submit a portion of home-made dung to fermentation, and will find satisfaction in knowing that this process, when well regulated, is not attended with any serious depreciation of the value of the manure. In the foregoing a.n.a.lyses he will find the direct proof that as long as heavy showers of rain are excluded from manure-heaps, or the manure is kept in water-proof pits, the most valuable fertilizing matters are preserved."