Talks on Manures - Part 46
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Part 46

Like cabbages, this crop requires a large amount of plant-food per acre; and, like them, it can only be grown by constant and high manuring. More manure must be used than the plants can take up out of the soil, and hence it is, that land which has been used for growing tobacco for some years, will be in high condition for other crops without further manuring.

Farm-yard or stable-manure, must be the mainstay of the tobacco-planter.

With this, he can use artificial fertilizers to advantage--such as fish-sc.r.a.p, woollen-rags, Peruvian guano, dried blood, slaughter-house offal, sulphate of ammonia, nitrate of soda, etc.

For choice, high-flavored smoking-tobacco, the grower aims to get quality rather than quant.i.ty. This seems to depend more on the land and the climate than on the manures used. Superphosphate of lime would be likely to prove advantageous in favoring the early growth and maturity of the crop. And in raising tobacco-plants in the seed-bed, I should expect good results from the use of superphosphate, raked into the soil at the rate of three or four lbs. per square rod.

MANURES FOR INDIAN CORN.

We know less about the manurial requirements of Indian corn, than of almost any other crop we cultivate. We know that wheat, barley, oats, and gra.s.ses, require for their maximum growth a liberal supply of available nitrogen in the soil. And such facts and experiments as we have, seem to indicate that the same is also true of Indian corn. It is, at any rate, reasonable to suppose that, as Indian corn belongs to the same botanical order as wheat, barley, oats, rye, timothy, and other gra.s.ses, the general manurial requirements would be the same. Such, I presume, is the case; and yet there seem to be some facts that would incline us to place Indian corn with the leguminous plants, such as clover, peas, and beans, rather than with the cereals, wheat, barley, oats, etc.

"Why so," asked the Deacon, "Indian corn does not have much in common with beans, peas, and clover?"

As we have shown, clover can get more nitrogen out of the soil, than wheat, barley, and oats. And the same is true of beans and peas, though probably not to so great an extent.

Now, it would seem that Indian corn can get more nitrogen out of a soil, than wheat, barley, or oats--and to this extent, at least, we may consider Indian corn as a renovating crop. In other words, the Indian corn can get more nitrogen out of the soil, than wheat, barley, and oats--and when we feed out the corn and stalks on the farm, we have more food and more manure than if we raised and fed out a crop of oats, barley, or wheat. If this idea is correct, then Indian corn, when consumed on the farm, should not be cla.s.sed with what the English farmers term "white crops," but rather with the "green crops." In other words, Indian corn is what old writers used to call a "fallow crop"--or what we call a renovating crop.

If this is so, then the growth and consumption of Indian corn on the farm, as is the case with clover, should leave the farm richer for wheat, rather than poorer. I do not mean richer absolutely, but richer so far as the _available_ supply of plant-food is concerned.

"It may be that you are right," said the Doctor, "when corn is grown for _fodder_, but not when grown for the grain. It is the formation of the seed which exhausts the soil."

If I could be sure that it was true of corn-fodder, I should have little doubt that it is true also of corn as ordinarily grown for grain and stalks. For, I think, it is clear that the grain is formed at the expense of the stalks, and not directly from the soil. The corn-fodder will take from the soil as much nitrogen and phosphoric acid as the crop of corn, and the more it will take, the more it approximates in character to clover and other renovating crops. If corn-fodder is a renovating crop, so is the ordinary corn-crop, also, provided it is consumed on the farm.

"But what makes you think," said the Deacon, "that corn can get more nitrogen from the soil, than wheat?"

"That is the real point, Deacon," said I, "and I will ask you this question. Suppose you had a field of wheat seeded down to clover, and the clover failed. After harvest, you plow up half of the field and sow it to wheat again, the other half of the field you plow in the spring, and plant with Indian corn. Now, suppose you get 15 bushels of wheat to the acre, how much corn do you think you would be likely to get?"

"Well, that depends," said the Deacon, "but I should expect at least 30 bushels of sh.e.l.led corn per acre."

"Exactly, and I think most farmers would tell you the same; you get twice as much corn and stalks to the acre as you would of wheat and straw. In other words, while the wheat cannot find more nitrogen than is necessary to produce 15 bushels of wheat and straw, the corn can find, and does find, take up, and organize, at least twice as much nitrogen as the wheat."

If these are facts, then the remarks we have made in regard to the value of clover as a fertilizing crop, are applicable in some degree to Indian corn. To grow clover and sell it, will in the end impoverish the soil; to grow clover and feed it out, will enrich the land. And the same will be true of Indian corn. It will gather up nitrogen that the wheat-crop can not appropriate; and when the corn and stalks are fed out, some 90 per cent of the nitrogen will be left in the manure.

"You do not think, then," said the Doctor, "that nitrogen is such an important element in manure for corn, as it is in a manure for wheat."

I have not said that. If we want a large crop of corn, we shall usually need a liberal supply of available nitrogen. But this is because a larger crop of corn means a much larger produce per acre, than a large crop of wheat. Forty bushels of wheat per acre is an unusually large crop with us; but 80 bushels of sh.e.l.led corn can be grown in a favorable season, and on rich, well-cultivated land. As the Deacon has said, 30 bushels of corn per acre can be grown as easily as 15 bushels of wheat; and it is quite probable, in many cases, that a manure containing no nitrogen, might give us a crop of 35 or 40 bushels per acre. In other words, up to a certain point, manures containing mineral, or carbonaceous matter, might frequently, in ordinary agriculture, increase the yield of Indian corn; while on similar land, such manures would have little effect on wheat.

"That is so," said the Deacon, "we all know that plaster frequently increases the growth of corn, while it seldom does much good on wheat."

But, after you have got as large a crop as the land will produce, aided by plaster, ashes, and superphosphate, say 40 bushels of sh.e.l.led corn per acre, _then_ if you want to raise 70 bushels per acre, you must furnish the soil with manures containing sufficient available nitrogen.

Some years ago, I made some careful experiments with artificial manures on Indian corn.

"Oh, yes," said the Deacon, "they were made on the south lot, in front of my house, and I recollect that the N.Y. State Ag. Society awarded you a prize of $75 for them."

"And I recollect," said I, "how you and some other neighbors laughed at me for spending so much time in measuring the land and applying the manures, and measuring the crop. But I wish I could have afforded to continue them. A single experiment, however carefully made, can not be depended on. However, I will give the results for what they are worth, with some remarks made at the time:

"The soil on which the experiments were made, is a light, sandy loam. It has been under cultivation for upwards of twenty years, and so far as I can ascertain has never been manured. It has been somewhat impoverished by the growth of cereal crops, and it was thought that for this reason, and on account of its light texture and active character, which would cause the manures to act immediately, it was well adapted for the purpose of showing the effect of different manurial substances on the corn-crop.

"The land was clover-sod, two years old, pastured the previous summer.

It was plowed early in the spring, and harrowed until in excellent condition. The corn was planted May 23, in hills 3 feet apart each way.

"The manures were applied in the hill immediately before the seed was planted.

"With superphosphate of lime, and with plaster (gypsum, or _sulphate of lime_), the seed was placed directly on top of the manure, as it is well known that these manures do not injure the germinating principle of even the smallest seeds.

"The ashes were dropped in the hill, and then covered with soil, and the seed planted on the top, so that it should not come in contact with the ashes.

"Guano and sulphate of ammonia were treated in the same way.

"On the plots where ashes and guano, or ashes and sulphate of ammonia were both used, the ashes were first put in the hill, and covered with soil, and the guano or sulphate of ammonia placed on the top, and also covered with soil before the seed was planted. The ashes and superphosphate of lime was also treated in the same way. It is well known that unleached ashes, mixed either with guano, sulphate of ammonia, or superphosphate, mutually decompose each other, setting free the ammonia of the guano and sulphate of ammonia, and converting the soluble phosphate of the superphosphate of lime into the insoluble form in which it existed before treatment with sulphuric acid. All the plots were planted on the same day, and the manures weighed and applied under my own immediate supervision. Everything was done that was deemed necessary to secure accuracy.

"The following table gives the results of the experiments:

Table Showing the Results of Experiments on Indian Corn.

SdC Bushels of ears of sound corn per acre.

SfC Bushels of ears of soft corn per acre.

TC Total No. of bushels of ears of corn per acre.

ISdC Increase per acre of ears sound corn.

ISfC Increase per acre of ears of soft corn.

TIC Total increase per acre of ears of corn.

-----+----------------------------------+-----+----+-----+----+----+----

Descriptions of manures and

Plots

quant.i.ties applied per acre

SdC

SfC

TC

ISdC

ISfC

TIC -----+----------------------------------+-----+----+-----+----+----+---- 1.

No manure

60

7

67

..

..

..

2.

100 lbs. plaster (gypsum or

sulphate of lime)

70

8

78

10

1

11 3.

400 lbs. unleached wood-ashes

and 100 lbs. plaster (mixed)

68

10

78

8

3

11 4.

150 lbs. sulphate of ammonia

90

15

105

30

8

38 5.

300 lbs. superphosphate of lime

70

8

78

10

1

11 6.

150 lbs. sulphate of ammonia

and 300 lbs. superphosphate of

lime (mixed)

85

5

90

25

..

23 7.

400 lbs. unleached wood-ashes,

(uncertain)

60

12

72

..

5

5 8.

150 lbs. sulphate of ammonia and

400 lbs. unleached wood-ashes

(sown separately)

87

10

97

27

3

30 9.

300 lbs. superphosphate of lime,

150 lbs. sulph. ammonia, and

400 lbs. unleached wood-ashes

100

8

108

40

1

41 10.

400 lbs. unleached wood-ashes

60

8

68

..

1

1 11.

100 lbs. plaster. 400 lbs.

unleached wood-ashes, 300 lbs.

superphosphate of lime, and

200 lbs. Peruvian guano

95

10

105

35

3

38 12.

75 lbs. sulphate of ammonia

78

10

88

18

3

21 13.

200 lbs. Peruvian guano

88

13

101

28

6

34 14.

400 lbs. unleached wood-ashes,

100 lbs. plaster, and

500 lbs. Peruvian guano

111

14

125

51

7

58 -----+----------------------------------+-----+----+-----+----+----+----

"The superphosphate of lime was made on purpose for these experiments, and was a pure mineral manure of superior quality, made from calcined bones; it cost about 2 cents per pound. The sulphate of ammonia was a good, commercial article, obtained from London, at a cost of about seven cents per pound. The ashes were made from beech and hard maple (_Acer saccharinum_) wood, and were sifted through a fine sieve before being weighed. The guano was the best Peruvian, costing about three cents per pound. It was crushed and sifted before using. In sowing the ashes on plot 7, an error occurred in their application, and for the purpose of checking the result, it was deemed advisable to repeat the experiment on plot 10.

"On plot 5, with 300 lbs. of superphosphate of lime per acre, the plants came up first, and exhibited a healthy, dark-green appearance, which they retained for some time. This result was not antic.i.p.ated, though it is well known that superphosphate of lime has the effect of stimulating the germination of turnip-seed, and the early growth of the plants to an astonishing degree; yet, as it has no such effect on wheat, it appeared probable that it would not produce this effect on Indian corn, which, in chemical composition, is very similar to wheat. The result shows how uncertain are all speculations in regard to the manurial requirements of plants. This immediate effect of superphosphate of lime on corn was so marked, that the men (who were, at the time of planting, somewhat inclined to be skeptical, in regard to the value of such small doses of manure), declared that 'superphosphate beats all creation for corn.' The difference in favor of superphosphate, at the time of hoeing, was very perceptible, even at some distance.

"Although every precaution was taken that was deemed necessary, to prevent the manures from mixing in the hill, or from injuring the seed, yet, it was found, that those plots dressed with ashes and guano, or with ashes and sulphate of ammonia, were injured to some extent. Shortly after the corn was planted, heavy rain set in, and washed the sulphate of ammonia and guano, down into the ashes, and mutual decomposition took place, with more or less loss of ammonia. In addition to this loss of ammonia, these manures came up to the surface of the ground in the form of an excrescence, so hard that the plants could with difficulty penetrate through it.

"It will be seen, by examining the table, that although the superphosphate of lime had a good effect during the early stages of the growth of the plants, yet the increase of ears of corn in the end did not come up to these early indications. On plot 5, with 300 lbs. of superphosphate of lime per acre, the yield is precisely the same as on plot 2, with 100 lbs. of plaster (_sulphate of lime_), per acre. Now, superphosphate of lime is composed necessarily of soluble phosphate of lime and plaster, or sulphate of lime, formed from a combination of the sulphuric acid, employed in the manufacture of superphosphate, with the lime of the bones. In the 300 lbs. of superphosphate of lime, sown on plot 5, there would be about 100 lbs. of plaster; and as the effect of this dressing is no greater than was obtained from the 100 lbs. of plaster, sown on plot 2, it follows, that the good effect of the superphosphate of lime was due to the plaster that it contained.

"Again, on plot 4, with 150 lbs. of sulphate of ammonia per acre, we have 90 bushels of ears of sound corn, and 15 bushels of ears of soft corn, ('nubbins,') per acre; or a total increase over the plot without manure, of 38 bushels. Now, the sulphate of ammonia contains no phosphate of lime, and the fact that such a manure gives a considerable increase of crop, confirms the conclusion we have arrived at, from a comparison of the results on plots 2 and 5; that the increase from the superphosphate of lime, is not due to the phosphate of lime which it contains, unless we are to conclude that the sulphate of ammonia rendered the phosphate of lime in the soil more readily soluble, and thus furnished an increased quant.i.ty in an available form for a.s.similation by the plants--a conclusion, which the results with superphosphate alone, on plot 5, and with superphosphate and sulphate of ammonia, combined, on plot 6, do not sustain.

"On plot 12, half the quant.i.ty of sulphate of ammonia, was used as on plot 4, and the increase is a little more than half what it is where double the quant.i.ty was used. Again, on plot 13, 200 lbs. of Peruvian guano per acre, gives nearly as great an increase of sound corn, as the 150 lbs. of sulphate of ammonia. Now, 200 lbs. of Peruvian guano contains nearly as much ammonia as 150 lbs. sulphate of ammonia, and the increase in both cases is evidently due to the ammonia of these manures.

The 200 lbs. of Peruvian guano, contained about 50 lbs. of phosphate of lime; but as the sulphate of ammonia, which contains no phosphate of lime, gives as great an increase as the guano, it follows, that the phosphate of lime in the guano, had little, if any effect; a result precisely similar to that obtained with superphosphate of lime.

"We may conclude, therefore, that on this soil, which has never been manured, and which has been cultivated for many years with the _Ceralia_--or, in other words, with crops which remove a large quant.i.ty of phosphate of lime from the soil--the phosphate of lime, relatively to the ammonia, is not deficient. If such was not the case, an application of soluble phosphate of lime would have given an increase of crop, which we have shown was not the case in any one of these experiments.

"Plot 10, with 400 lbs. of unleached wood-ashes per acre, produces the same quant.i.ty of _sound corn_, with an extra bushel of 'nubbins' per acre, as plot 1, without any manure at all; ashes, therefore, applied alone, may be said to have had no effect whatever. On plot 3, 400 lbs.

of ashes, and 100 lbs. of plaster, give the same total number of bushels per acre, as plot 2, with 100 lbs. of plaster alone. Plot 8, with 400 lbs. ashes, and 150 lbs. of sulphate of ammonia, yields three bushels of sound corn, and five bushels of 'nubbins' per acre, _less_ than plot 4, with 150 lbs. sulphate of ammonia alone. This result may be ascribed to the fact previously alluded to--the ashes dissipated some of the ammonia.

"Plot 11, with 100 lbs. of plaster, 400 lbs. ashes, 300 lbs. of superphosphate of lime, and 200 lbs. Peruvian guano (which contains about as much ammonia as 150 lbs. sulphate of ammonia), produced precisely the same number of total bushels per acre, as plot 4, with 150 lbs. sulphate of ammonia alone, and but 4 bushels more per acre, than plot 13, with 200 lbs. Peruvian guano alone. It is evident, from these results, that neither ashes nor phosphates had much effect on Indian corn, on this impoverished soil. Plot 14 received the largest dressing of ammonia (500 lbs. Peruvian guano), and produced much the largest crop; though the increase is not so great in proportion to the guano, as where smaller quant.i.ties were used.

"The manure which produced the most profitable result, was the 100 lbs.