Talks on Manures Part 28

"It is curious," said the Doctor, "that 3 cwt. of ammonia-salts alone on plots 9 and 10 should produce as much wheat as was obtained from plot 2, where 14 tons of barn-yard manure had been applied two years in succession. I notice that on one plot, the ammonia-salts were applied at once, in the spring, while on the other plot they were sown at four different times--and that the former gave the best results."

The only conclusion to be drawn from this, is, that it is desirable to apply the manure _early_ in the spring--or better still, in the autumn.

"You are a great advocate of Peruvian guano," said the Deacon, "and yet 3 cwt. of Peruvian guano on Plot 13, only produced an increase of two bushels and 643 lbs. of straw per acre. The guano at $60 per ton, would cost $9.00 per acre. This will not pay."

This is an unusually small increase. The reason, probably, is to be found in the fact that the manure and seed were not sown until March, instead of in the autumn. The salts of ammonia are quite soluble and act quickly; while the Peruvian guano has to decompose in the soil, and consequently needs to be applied earlier, especially on clay land.

"I do not want you," said the Deacon, "to dodge the question why an application of 14 tons of farmyard-manure per acre, every year for over thirty years, does not make the land too rich for wheat."

"Possibly," said I, "on light, sandy soil, such an annual dressing of manure _would_ in the course of a few years make the land too rich for wheat. But on a clayey soil, such is evidently not the case. And the fact is a very important one. When we apply manure, our object should be to make it as available as possible. Nature preserves or conserves the food of plants. The object of agriculture is to use the food of plants for our own advantage."

"Please be a little more definite," said the Deacon, "for I must confess I do not quite see the significance of your remarks."

"What he means," said the Doctor, "is this: If you put a quant.i.ty of soluble and available manure on land, and do not sow any crop, the manure will not be wasted. The soil will retain it. It will change it from a soluble into a comparatively insoluble form. Had a crop been sown the first year, the manure would do far more good than it will the next year, and yet it may be that none of the manure is lost. It is merely locked up in the soil in such a form as will prevent it from running to waste. If it was not for this principle, our lands would have been long ago exhausted of all their available plant-food."

"I think I understand," said the Deacon; "but if what you say is true, it upsets many of our old notions. We have thought it desirable to plow under manure, in order to prevent the ammonia from escaping. You claim, I believe, that there is little danger of any loss from spreading manure on the surface, and I suppose you would have us conclude that we make a mistake in plowing it under, as the soil renders it insoluble."

"It depends a good deal," said I, "on the character of the soil.

A light, sandy soil will not preserve manure like a clay soil. But it is undoubtedly true that our aim in all cases should be to apply manure in such a form and to such a crop as will give us the greatest _immediate_ benefit. Plowing under fresh manure every year for wheat is evidently not the best way to get the greatest benefit from it. But this is not the place to discuss this matter. Let us look at the result of Mr.

Lawes' experiments on wheat the third year:"

Experiments at Rothamsted on the Growth of Wheat, Year After Year, on the Same Land.

Table III.--Manures and Produce; 3rd Season, 1845-6. Manures and Seed (Old Red Lammas), Sown Autumn, 1845.

Manures FM Farmyard Manure.

A3W Ash from 3 loads (3,888 lbs.) Wheat-straw.

LWM Liebig's Wheat-manure.

PG Peruvian Guano.

SPL Superphosphate of Lime.

SiP Silicate of Pota.s.s.[1]

P-A Pearl-ash.

S-A Soda-ash.

MLS Magnesian Lime-stone.

B-A Bone-ash.

SAc Sulphuric Acid (Sp. gr. 1-7.) MAc Muriatic Acid.

SAm Sulphate of Ammonia.

MAm Muriate of Ammonia.

RC Rape-Cake.

-----+--------------------------------------------------------------+ Manures per Acre. P +-----+-----+---+---+-----------+---+---+---+---+------+---+---+ l o SPL t +-----------+ s FM A3W LWM PG SiP P-A S-A MLS B-A SAc MAc SAm MAm RC -----+-----+-----+---+---+---+---+---+---+---+---+---+------+---+---+ Tons. lbs. lbs lbs bs. lbs lbs lbs lbs lbs lbs lbs. lbs lbs 0 .. .. .. 336 .. .. .. .. .. .. .. .. .. .. 1 .. .. .. .. .. .. .. .. 224 .. .. .. .. .. 2 14 .. .. .. .. .. .. .. .. .. .. .. .. .. 3 Unmanured. .. .. .. .. .. .. .. .. .. .. .. .. 4 .. .. .. .. .. .. .. .. 224 .. 224 224 .. .. 5a{1 ..} {.. .. .. .. .. .. .. .. .. .. .. .. {2 ..} Straw {.. .. .. .. .. .. .. .. .. 224[1] .. .. 5b{1 ..} Ash {.. .. .. .. .. .. .. .. .. .. .. 448 {2 ..} {.. .. .. .. .. .. .. .. .. 224[1] .. 448 6a .. .. 448 .. .. .. .. .. .. .. .. .. .. .. 6b .. .. 448 .. .. .. .. .. .. .. .. 112 112 .. 7a .. .. 448 .. .. .. .. .. .. .. .. .. .. 448 7b .. .. 448 .. .. .. .. .. .. .. .. 112 112 448 8a .. .. .. .. .. .. .. .. 224 .. .. .. .. 448 8b .. .. .. .. .. .. .. .. 224 .. .. 112 112 .. 9a .. .. .. .. .. .. .. .. .. .. .. .. .. 448 9b .. .. .. .. .. .. .. .. .. .. .. 224 .. 448 10a .. .. .. .. .. .. .. .. .. .. .. 224 .. .. 10b Unmanured. .. .. .. .. .. .. .. .. .. .. .. .. 11a .. .. .. .. .. .. .. .. 224 224 .. .. .. 448 11b .. .. .. .. .. .. .. .. 224 224 .. 112 112 .. 12a .. .. .. .. .. .. 180 .. 224 224 .. .. .. 448 12b .. .. .. .. .. .. 180 .. 224 224 .. 112 112 .. 13a .. .. .. .. .. 200 .. .. 224 224 .. .. .. 448 13b .. .. .. .. .. 200 .. .. 224 224 .. 112 112 .. 14a .. .. .. .. .. .. .. 84 224 224 .. .. .. 448 14b .. .. .. .. .. .. .. 84 224 224 .. 112 112 .. 15a .. .. .. .. .. .. .. .. 224 .. 224 224 .. 448 15b .. .. .. .. 224 .. .. .. 224 .. 224 224 .. 448 16a .. .. .. .. .. 67 60 84 224 224 .. .. .. 448 16b .. .. .. .. .. 67 60 84 224 224 .. 224 .. 448 17a .. .. .. .. .. 67 60 84 224 224 .. 112 11 448 17b .. .. .. .. .. 67 60 84 224 224 .. 224 .. .. 18a .. .. .. .. .. 67 60 84 224 224 .. 112 11 .. 18b .. .. .. .. .. 67 60 84 224 224 .. .. .. .. 19 .. .. .. .. .. .. .. .. 112 .. 112 112 .. 448 20 } 21 } Mixture of the residue of .. .. .. .. .. .. 22 } most of the other manures. -----+-----+-----+---+---+---+---+---+---+---+---+---+------+---+---+

Produce: Wt/Bu Weight per Bushel.

OC Offal Corn.

TC Total Corn.

S&C Straw and Chaff.

TP Total Produce (Corn and Straw).

C Corn.

TP Total Produce.

OCD Offal Corn to 100 Dressed.

C100 Corn to 100 Straw.

----------------------------------+------------------+-----+-----+---- Increase per Produce per Acre, etc. Acre by Manure. P --------------+----+----+----+----+-----+-----+------+ l Dressed Corn. o --------+-----+ t Qty. Wt/Bu OC TC S&C TP C S&C TP OCD C100 s --------+-----+----+----+----+----+-----+-----+------+-----+-----+---- Bu. Pks. lbs. lbs. lbs. lbs. lbs. lbs. lbs. lbs. 28 1 62.3 134 1906 2561 4467 699 1048 1747 7.3 74.4 0 22 0 62.6 120 1509 1953 3462 302 440 742 8.1 77.3 1 27 0 63.0 113 1826 2454 4280 619 941 1560 6.6 74.4 2 17 3 63.8 64 1207 1513 2720 .. .. .. 7.4 79.7 3 25 3 63.5 130 1777 2390 4167 570 877 1447 7.8 74.3 4 19 0 63.7 87 1305 1541 2846 98 28 126 .. 84.6 1}5a 27 0 63.0 126 1827 2309 4136 620 796 1416 .. 79.1 2} 23 2 63.4 100 1598 1721 3319 391 208 599 .. 92.8 1}5b 30 0 63.3 165 2076 2901 4977 869 1388 2257 .. 71.6 2} 20 1 63.7 102 1400 1676 3076 193 163 356 7.0 83.6 6a 29 0 63.5 114 1967 2571 4538 760 1058 1818 5.3 76.5 6b 22 3 63.0 97 1534 1968 3502 327 405 732 6.8 77.9 7a 31 3 63.4 150 2163 3007 5170 956 1494 2450 7.5 72.6 7b 22 3 63.5 101 1549 1963 3512 342 450 792 7.1 78.9 8a 29 0 63.6 132 1988 2575 4563 781 1062 1843 7.2 77.2 8b 23 2 63.0 122 1614 2033 3647 407 520 927 7.9 79.4 9a 28 3 63.3 114 1942 2603 4545 735 1090 1825 7.0 74.6 9b 27 1 63.6 109 1850 2244 4094 643 731 1374 6.4 82.4 10a 17 2 63.8 92 1216 1455 2671 9 -58 -49 7.8 83.6 10b 23 1 63.3 145 1628 2133 3761 421 620 1041 9.8 76.3 11a 30 0 63.2 155 2055 2715 4770 848 1202 2050 6.1 75.7 11b 24 1 63.0 125 1661 2163 3824 454 650 1104 7.9 76.8 12a 28 2 63.4 136 1955 2554 4509 748 1041 1789 7.4 76.5 12b 24 0 63.5 136 1660 2327 3987 453 814 1267 9.1 71.3 13a 29 1 63.2 138 1998 2755 4753 791 1242 2033 7.3 72.5 13b 23 2 63.0 117 1605 2031 3636 398 518 916 7.7 79.0 14a 26 2 63.4 124 1812 2534 4356 605 1021 1626 7.4 71.5 14b 31 1 62.5 147 2112 2936 5048 905 1423 2328 7.5 71.9 15a 27 2 63.0 117 1861 2513 4374 654 1000 1654 5.9 74.0 15b 23 3 62.5 108 1592 2967 3659 385 554 939 7.0 77.0 16a 30 1 62.7 122 2019 2836 4855 812 1323 2135 6.6 71.2 16b 33 2 62.8 129 2241 3278 5519 1034 1765 2799 5.8 68.3 17a 30 2 63.0 113 2034 2784 4818 827 1271 2098 5.9 73.0 17b 31 0 62.8 103 2048 2838 4886 841 1325 2166 5.1 72.2 18a 21 1 62.0 157 1474 1893 3367 267 380 647 6.6 77.1 18b 28 3 62.0 107 1889 2425 4314 682 912 1594 5.8 77.9 19 {20 .. .. .. .. .. .. .. .. .. .. .. .. {21 {22 --------+-----+----+----+----+----+-----+-----+------+-----+-----+----

[Note 1: Top-dressed in the Spring.]

This year, the seed and manures were sown in the autumn. And I want the Deacon to look at plot 0. 3 cwt. of Peruvian guano here gives an increase of 10 bushels of wheat, and 1,948 lbs. of straw per acre. This will pay _well_, even on the wheat alone. But in addition to this, we may expect, in our ordinary rotation of crops, a far better crop of clover where the guano was used.

In regard to some of the results this year, Messrs. Lawes and Gilbert have the following concise and interesting remarks:

"At this third experimental harvest, we have on the continuously unmanured plot, namely, No. 3, not quite 18 bushels of dressed corn, as the normal produce of the season; and by its side we have on plot 10_b_--comprising one-half of the plot 10 of the previous years, and so highly manured by ammoniacal salts in 1845, but now unmanured--rather more than 17 bushels. The near approach, again, to ident.i.ty of result from the two unmanured plots, at once gives confidence in the accuracy of the experiments, and shows us how effectually the preceding crop had, in a practical point of view, reduced the plots, previously so differently circ.u.mstanced both as to manure and produce, to something like an uniform standard as regards their grain-producing qualities.

"Plot 2 has, as before, 14 tons of farm-yard manure, and the produce is 27 bushels, or between 9 and 10 bushels more than without manure of any kind.

"On plot 10_a_, which in the previous year gave by ammoniacal salts alone, a produce equal to that of the farm-yard manure, we have again a similar result: for two cwts. of sulphate of ammonia has now given 1,850 lbs. of total corn, instead of 1,826 lbs., which is the produce on plot 2. The straw of the latter, is, however, slightly heavier than that by the ammoniacal salt.

"Again, plot 5_a_, which was in the previous season _unmanured_, was now subdivided: on one-half of it (namely, 5_a_1) we have the ashes of wheat-straw alone, by which there is an increase of rather more than one bushel per acre of dressed corn; on the other half (or 5_a_2) we have, besides the straw-ashes, two cwts. of sulphate of ammonia put on as a top-dressing: two cwts. of sulphate of ammonia have, in this case, only increased the produce beyond that of 5_a_1 by 7? bushels of corn and 768 lbs. of straw, instead of by 9 bushels of corn and 789 lbs. of straw, which was the increase obtained by the same amount of ammoniacal salt on 10_a_, as compared with 10_b_.

"It will be observed, however, that in the former case the ammoniacal salts were top-dressed, but in the latter they were drilled at the time of sowing the seed; and it will be remembered that in 1845 the result was better _as to corn_ on plot 9, where the salts were sown earlier, than on plot 10, where the top-dressing extended far into the spring. We have had several direct instances of this kind in our experience, and we would give it as a suggestion, in most cases applicable, that manures for wheat, and especially ammoniacal ones, should be applied before or at the time the seed is sown; for, although the apparent luxuriance of the crop is greater, and the produce of straw really heavier, by spring rather than autumn sowings of Peruvian guano and other ammoniacal manures, yet we believe that that of the _corn_ will not be increased in an equivalent degree. Indeed, the success of the crop undoubtedly depends very materially on the progress of the underground growth during the winter months; and this again, other things being equal, upon the quant.i.ty of available nitrogenous const.i.tuents within the soil, without a liberal provision of which, the range of the fibrous feeders of the plant will not be such, as to take up the minerals which the soil is competent to supply, and in such quant.i.ty as will be required during the after progress of the plant for its healthy and favorable growth."

These remarks are very suggestive and deserve special attention.

"The next result to be noticed," continue Messrs. Lawes and Gilbert, "is that obtained on plot 6, now also divided into two equal portions designated respectively 6_a_ and 6_b_. Plot No. 6 had for the crop of 1844, superphosphate of lime and the phosphate of magnesia manure, and for that of 1845, superphosphate of lime, rape-cake, and ammoniacal salts. For this, the third season, it was devoted to the trial of the wheat-manure manufactured under the sanction of Professor Liebig, and patented in this country.

"Upon plots 6_a_, four cwts. per acre of the patent wheat-manure were used, which gave 20 bushels, or rather more than two bushels beyond the produce of the unmanured plot; but as the manure contained, besides the minerals peculiar to it, some nitrogenous compounds, giving off a very perceptible odor of ammonia, some, at least, of the increase would be due to that substance. On plot 6_b_, however, the further addition of one cwt. each of sulphate and muriate of ammonia to this so-called 'Mineral Manure,' gives a produce of 29 bushels. In other words, the addition of ammoniacal salt, to Liebig's mineral manure has increased the produce by very nearly 9 bushels per acre beyond that of the mineral manure alone, whilst the increase obtained over the unmanured plot, by 14 tons of farm-yard manure, was only 9 bushels!

The following table gives the results of the experiments the _fourth_ year, 1846-7.

Experiments at Rothamsted on the Growth of Wheat, Year After Year, on the Same Land.

Table IV.--Manures and Produce; 4th Season, 1846-7. Manures and Seed (Old Red Lammas), Sown End of October, 1846.

Manures FM Farm-yard Manure.

PG Peruvian Guano.

B-A Bone-ash.

SAc Sulphuric Acid (Sp. gr. 1-7.) MAc Muriatic Acid.

SAm Sulphate of Ammonia.

MAm Muriate of Ammonia.

R Rice.

-----+--------------------------------------------------------+ Manures per Acre. P +-------+------+--------------------+------+------+------+ l Superphosphate o of Lime t +------+------+------+ s FM PG B-A SAc MAc SAm MAm R -----+-------+------+------+------+------+------+------+------+ Tons. lbs. lbs. lbs. lbs. lbs. lbs. lbs. 0 .. 500 .. .. .. .. .. .. 1 .. .. 200 .. 200 350 50 .. 2 14 .. .. .. .. .. .. .. 3 Unmanured. .. .. .. .. .. .. 4 .. .. 200 .. 200 300 .. .. 5a .. .. 200 200 .. 150 150 .. 5b .. .. 200 200 .. 150 150 500 6a .. .. .. .. .. 150 150 .. 6b .. .. .. .. .. 150 150 .. 7a .. .. .. .. .. 150 150 .. 7b .. .. .. .. .. 150 150 .. 8a .. .. 200 200 .. 150 150 500 8b .. .. 200 200 .. 200 200 .. 9a{1 .. .. .. .. .. .. .. 2240 {2 .. .. .. .. .. 150 150 .. 9b .. .. .. .. .. 150 150 .. 10a .. .. .. .. .. 150 150 .. 10b .. .. .. .. .. 150 150 .. 11a .. .. 100 100 .. 150 150 .. 11b .. .. 100 100 .. 150 150 .. 12a .. .. 100 100 .. 150 150 .. 12b .. .. 100 100 .. 150 150 .. 13a .. .. 100 100 .. 150 150 .. 13b .. .. 100 100 .. 150 150 .. 14a .. .. 100 100 .. 150 150 .. 14b .. .. 100 100 .. 150 150 .. 15a .. .. 200 .. 200 300 .. 500 15b .. .. 200 .. 200 300 .. 500 16a .. .. 100 100 .. 150 150 .. 16b .. .. 100 100 .. 150 150 .. 17a .. .. 100 100 .. 150 150 .. 17b .. .. 100 100 .. 200 200 .. 18a .. .. 100 100 .. 150 150 .. 18b .. .. 100 100 .. 150 150 .. 19 .. .. 100 .. 100 300 .. 500 20 Unmanured. .. .. .. .. .. .. 21 } Mixture of the residue of most of the .. .. 22 } other manures. .. .. -----+-------+------+------+------+------+------+------+------+

Produce Wt/Bu Weight per Bushel.

OC Offal Corn.

TC Total Corn.

S&C Straw and Chaff.