1. Averages of 4 years, 4 years, and 8 years.
2. Averages of 9 years, (1853-’61), last 10 years, and total 19 years.
3. Averages of 7 years (1855-’61), last 10 years, and total 17 years.
4. Averages of 9 years (1853-’61), last 10 years, and total 19 years.
1st 10:First ten Years, 1852-’61.
2nd 10:Second ten Years, 1862-’71.
T20:Total Period, 20 Years, 1852-’71.
1. Averages of 4 years, 4 years, and 8 years.
2. Averages of 9 years, (1853-’61), last 10 years, and total 19 years.
3. Averages of 7 years (1855-’61), last 10 years, and total 17 years.
4. Averages of 9 years (1853-’61), last 10 years, and total 19 years.
1st 10:First ten Years, 1852-’61.
2nd 10:Second ten Years, 1862-’71.
T20:Total Period, 20 Years, 1852-’71.
1. Averages of 4 years, 4 years, and 8 years.
2. Averages of 9 years, (1853-’61), last 10 years, and total 19 years.
3. Averages of 7 years (1855-’61), last 10 years, and total 17 years.
4. Averages of 9 years (1853-’61), last 10 years, and total 19 years.
1st 10:First ten Years, 1852-’61.
2nd 10:Second ten Years, 1862-’71.
T20:Total Period, 20 Years, 1852-’71.
1. Averages of 4 years, 4 years, and 8 years.
2. Averages of 9 years, (1853-’61), last 10 years, and total 19 years.
3. Averages of 7 years (1855-’61), last 10 years, and total 17 years.
4. Averages of 9 years (1853-’61), last 10 years, and total 19 years.
The produce of barley the first season (1852), was, per acre:
With potash, soda, and magnesia and superphosphate
With 200 lbs. ammonia-salts and superphosphate
With 200 lbs. ammonia-salts and potash, soda, and magnesia
With 200 lbs. ammonia-salts and superphosphate, potash, soda, and magnesia
The 200 lbs. of ammonia-salts contain 50 lbs. of ammonia = 41 lbs. nitrogen.
It will be seen that this 50 lbs. of ammonia alone, on plot 1a, gives an increase of nearly 10 bushels per acre, or to be more accurate, it gives an increase over the unmanured plot of 503 lbs. of grain, and 329 lbs. of straw, while double the quantity of ammonia on plot 1a.a., gives an increase of 17¼ bushels per acre—or an increase of 901 lbs. of grain, and 1,144 lbs. of straw.
“Put that fact in separate lines, side by side,” said the Deacon, “so that we can see it.”
50 lbs. of ammonia gives an increase of
100 lbs. of ammonia gives an increase of
The first 50 lbs. of ammonia gives an increase of
The second 50 lbs. of ammonia gives an increase of
“That shows,” said the Deacon, “that a dressing of 50 lbs. per acre pays better than a dressing of 100 lbs. per acre. I wish Mr. Lawes had sown 75 lbs. on one plot.”
I wish so, too, but it is quite probable that in our climate, 50 lbs. of available ammonia per acre is all that it will usually be profitable to apply per acre to the barley crop. It is equal to a dressing of 500 lbs. guaranteed Peruvian guano, or 275 lbs. nitrate of soda. —“Or to how much manure?” asked the Deacon.
To about 5 tons of average stable-manure, or say three tons of good, well-rotted manure from grain-fed animals.
“And yet,” said the Deacon, “Mr. Lawes put on 14 tons of yard manure per acre, and the yield of barley was not as much as from the 50 lbs. of ammonia alone. How do you account for that?”
Simply because the ammonia in the manure isnotammonia. It is what the chemists used to call “potential ammonia.” A good deal of it is in the form of undigested straw and hay. The nitrogenous matter of the food which has been digested by the animaland thrown off in the liquid excrements, is in such a form that it will readily ferment and produce ammonia, while the nitrogenous matter in the undigested food and in the straw used for bedding, decomposes slowly even under the most favorable conditions; and if buried while fresh in a clay soil, it probably would not all decompose in many years. But we will not discuss this at present.
“The superphosphate does not seem to have done much good,” said the Deacon; “3½ cwt. per acre gives an increase of less than two bushels per acre. And I suppose it wasgoodsuperphosphate.”
There need be no doubt on that point. Better superphosphate of lime cannot be made. But you must recollect that this is pure superphosphate made from burnt bones. It contains no ammonia or organic matter. Commercial superphosphates contain more or less ammonia, and had they been used in these experiments, they would have shown a better result than the pure article. They would have done good in proportion to the available nitrogen they contained. If these experiments prove anything, they clearly indicate that superphosphate alone is a very poor manure for either wheat or barley.
Thesecondyear, the unmanured plot gave 25¾ bushels per acre. Potash, soda, and magnesia, (or what the Deacon calls “ashes,”) 27⅝ bushels; superphosphate 33½, and “ashes” and superphosphate, nearly 36 bushels per acre.
50 lbs. of ammonia, alone, gives nearly 39 bushels, and ammonia and superphosphate together, 40 bushels.
The superphosphate and “ashes” give a better account of themselves this year; but it is remarkable that the ammonia alone, gives almost as good a crop as the ammonia and superphosphate, and abettercrop than the ammonia and “ashes,” or the ammonia, superphosphate, and ashes, together.
The 14 tons farm-yard manure gives over 36 bushels per acre. This plot has now had 28 tons of manure per acre, yet the 50 lbs. of ammonia alone, still gives a better yield than this heavy dressing of manure.
Thethirdseason (1854), was quite favorable for the ripening of wheat and barley. The seed on the experimental barley-field, was sown Feb. 24, and the harvest was late; so that the crop had an unusually long season for growth. It was one of the years when even poor land, if clean, gives a good crop. The unmanured plot, it will be seen, yielded over 35 bushels per acre of dressed grain, weighing over 53½ lbs. per bushel. The total weight of grain, was 1,963 lbs. This is over 40 bushels per acre, of 48 lbs. per bushel, which is the standard with us.
The 14 tons of farm-yard manure produce nearly 56½ bushels per acre.
You will see, that though the plot which has received 42 tons of manure per acre, produced a splendid crop; the plot having nothing except 100 lbs. of ammonia per acre, produced a crop equally good. “How much increase do you get from 50 lbs. of ammonia,” asked the Deacon, “and how much from 100 lbs.?”
50 lbs. of ammonia, gives an increase of
100 lbs. of ammonia, gives an increase of
If you buy nitrate of soda at 3¾ cents a lb., the ammonia will cost 20 cents a lb. In the above experiment, 50 lbs. of ammonia, costing $10, gives an increase of 16⅔ bushels of barley, and nearly half a ton of straw. If the straw is worth $4.00 per ton, the barley will cost 48 cents a bushel.
Double the quantity of manure, costing $20, gives an increase of 28 bushels of barley, and over one ton of straw. In this case the extra barley costs 57 cents a bushel.
On plot 2a., 50 lbs. of ammonia and 3½ cwt. of superphosphate, give 3,437 lbs. of grain, equal to 71½ of our bushels per acre.
On plot 2a.a., 100 lbs. of ammonia and 3½ cwt. of superphosphate, give 3,643 lbs. of grain, which lacks only 5 lbs. of 76 bushels per acre, and nearly 2½ tons of straw.
“That will do,” said the Deacon, “but I see that in 1857, this same plot, with the same manure, produced 66½ bushels of dressed grain per acre, weighing 53½ lbs. to the bushel, or a total weight of 3,696 lbs., equal to just 77 of our bushels per acre.”
“And yet,” said the Doctor, “this same year, the plot which had 84 tons of farm-yard manure per acre, produced only 2,915 lbs. of grain, or less than 61 of our bushels of barley per acre.”
The Squire happened in at this time, and heard the last remark. “What are you saying,” he remarked, “aboutonly61 bushels of barley per acre. I should like to see such a crop. Last year, in this neighborhood, there were hundreds of acres of barley that did not yield 20 bushels per acre, and very little of it would weigh 44 lbs. to the bushel.”
This is true. And the maltsters find it almost impossible to get six-rowed barley weighing 48 lbs. per bushel. They told me, that they would pay $1.10 per bushel for good bright barley weighing 48 lbs. per bushel, and for each pound it weighed less than this, they deducted 10 cents a bushel from the price. In other words,they would pay $1.00 a bushel for barley weighing 47 lbs. to the bushel; 90 cents for barley weighing 46 lbs.; 80 cents for barley weighing 45 lbs., and 70 cents for barley weighing 44 lbs.—and at these figures they much preferred the heaviest barley.
It is certainly well worth our while, if we raise barley at all, to see if we cannot manage not only to raise larger crops per acre, but to produce barley of better quality. And these wonderful experiments of Mr. Lawes are well worth careful examination and study.
The Squire put on his spectacles and looked at the tables of figures.
“Like everybody else,” said he, “you pick out the big figures, and to hear you talk, one would think you scientific gentlemen never have any poor crops, and yet I see that in 1860, there are three different crops of only 12⅛, 12¼, and 13¼ bushels per acre.”
“Those,” said I, “are the three plots which have grown barley every year without any manure, and you have selected the worst year of the whole twenty.”
“Perhaps so,” said the Squire, “but we have got to take the bad with the good, and I have often heard you say that a good farmer who has his land rich and clean makes more money in an unfavorable than in a favorable season. Now, this year 1860, seems to have been an unfavorable one, and yet your pet manure, superphosphate, only gives anincreaseof 148 lbs. of barley—or three bushels and 4 lbs. Yet this plot has had a tremendous dressing of 3½ cwt. of superphosphate yearly since 1852. I always told you you lost money in buying superphosphate.”
“That depends on what you do with it. I use it for turnips, and tomatoes, cabbages, lettuce, melons, cucumbers, etc., and would not like to be without it; but I have never recommended any one to use it on wheat, barley, oats, Indian corn, or potatoes, except as an experiment. What I have recommended you to get for barley is, nitrate of soda, and superphosphate, or Peruvian guano. And you will see that even in this decidedly unfavorable season, the plot 2a.a., dressed with superphosphate and 275 lbs. of nitrate of soda, produced 2,338 lbs. of barley, or 48¾ bushels per acre. This is anincreaseover the unmanured plots of 33½ bushels per acre, and anincreaseof 1,872 lbs. of straw. And the plot dressed with superphosphate and 200 lbs. of salts of ammonia, gave equally as good results.”
And this, mark you, is the year which the Squire selected as the one most likely to show that artificial manures did not pay.
“I never knew a man except you,” said the Squire, “who wanted unfavorable seasons.”
I have never said I wanted unfavorable seasons. I should not dare to say so, or even to cherish the wish for one moment. But I do say, that when we have a season so favorable that even poorly worked land will produce a fair crop, we are almost certain to have prices below the average cost of production. But when we have an unfavorable season, such crops as barley, potatoes, and beans, often advance to extravagantly high prices, and the farmer who has good crops in such a season, gets something like adequate pay for his patient waiting, and for his efforts to improve his land.
“That sounds all very well,” said the Squire, “but will it pay to use these artificial manures?”
I do not wish to wander too much from the point, but would like to remark before I answer that question, that I am not a special advocate of artificial manures. I think we can often make manures on our farms far cheaper than we can buy them. But as the Squire has asked the question, and as he has selected from Mr. Lawes’ results, the year 1860, I will meet him on his own ground. He has selected a season specially unfavorable for the growth of barley. Now, in such an unfavorable year in this country, barley would be likely to bring, at least, $1.25 per bushel, and in a favorable season not over 75 cents a bushel.
Mr. Lawes keeps his landclean, which is more than can be said of many barley-growers. And in this unfavorable season of 1860, he gets on his three unmanured plots an average of 730 lbs. of barley, equal to 15¼ bushels per acre, and not quite 800 lbs. of straw.
Many of our farmers frequently do no better than this. And you must recollect that in such careful experiments as those of Mr. Lawes and Dr. Gilbert, great pains would be taken to get all the barley that grew on the land. With us, barley is cut with a reaper, and admirable as our machines are, it is not an easy matter to cut a light, spindling crop of barley perfectly clean. Then, in pitching the crop and drawing it in, more or less barley is scattered, and even after we have been over the field two or three times with a steel-tooth rake, there is still considerable barley left on the ground. I think we may safely assume that at least as much barley is left on the ground as we usually sow—say two bushels per acre. And so, instead of having 15¼ bushels per acre, as Mr. Lawes had, we should only harvest 13¼ bushels.
Of all our ordinary farm crops, barley is attended with the least labor and expense. We usually sow it after corn or potatoes. On such strong land as that of Mr. Lawes, we ought to plow the landin the autumn and again in the spring, or at least stir up the land thoroughly with a two or three-horse cultivator or gang-plow.
Let us say that the cost of plowing, harrowing, drilling, and rolling, is $5.00 per acre. Seed, $2.00. Harvesting, $2.00. Threshing, 6 cents a bushel.
Receipts:
800 lbs. of straw @ $4. per ton
Putting in and harvesting the crop
Threshing 13¼ bushels @ 6c
“That is a better showing than I expected,” said the Squire, “and as barley occupies the land only a few months, and as we sow wheat after it, we cannot expect large profits.”
“Very well,” said I, “Now let us take the crop, this same unfavorable year, on plot 2a.a., dressed with superphosphate and nitrate of soda.”
The expense of plowing, harrowing, drilling, rolling, seed, and harvesting, would be about the same, or we will say $2.00 an acre more for extra labor in harvesting. And we will allow two bushels per acre for scatterings—though there is nothing like as much barley left on the ground when we have a good crop, as when we have a poor crop. But I want to be liberal.
The yield on plot 2a.a., was 48¾ bushels per acre, and 2,715 lbs. of straw.
Receipts:
2,715 lbs. straw @ $4. per ton
Putting in the crop and harvesting
275 lbs. nitrate of soda @ 4 c
In ordinary farm practice, I feel sure we can do better than this. Growing barley year after year on the same land, is not the most economical way of getting the full value of the manure. There is much nitrogen and phosphoric acid left in the land, which barley or even wheat does not seem capable of taking up, but which would probably be of great benefit to the clover.
The old notion that there is any real chemical necessity for a rotation of crops is unfounded. Wheat can be grown after wheat, and barley after barley, and corn after corn, provided we use the necessary manures and get the soil clean and in the right mechanical condition.
“What, then, do we gain by a rotation?” asked the Deacon.
Much every way. A good rotation enables us to clean the land. We can put in different crops at different seasons.
“So we could,” broke in the Deacon, “if we sowed wheat after wheat, barley after barley, and corn after corn.”
True, but if we sowed winter-wheat after winter-wheat, there would not be time enough to clean the land.
“Just as much as when we sow wheat after oats, or peas, or barley.”
“True again, Deacon,” I replied, “but we are supposed to have cleaned the land while it was in corn the previous year. I say supposed, because in point of fact, many of our farmers do not half clean their land while it is in corn. It is the weak spot in our agriculture. If our land was as clean as it should be to start with, there is no rotation so convenient in this section, as corn the first year, barley, peas, or oats the second year, followed by winter-wheat seeded down. But to carry out this rotation to the best advantage we need artificial manures.”
“But will they pay?” asks the Deacon.
“They will pay well, provided we can get them at a fair price and get fair prices for our produce. If we could get a good superphosphate made from Charleston phosphates for 1½ cent per lb., and nitrate of soda for 3½ or 4 cents per lb., and the German potash-salts for ¾ cent per lb., and could get on the average $1.25 per bushel for barley, and $1.75 for good white wheat, we could use these manures to great advantage.”
“Nothing like barn-yard manure,” says the Deacon.
No doubt on that point, provided it is good manure. Barn-yard manure, whether rich or poor, contains all the elements of plant-food, but there is a great difference between rich and poor manure. The rich manure contains twice or three times as much nitrogen and phosphoric acid as ordinary or poor manure. And this is the reason why artificial manures are valuable in proportion to the nitrogen and phosphoric acid that they contain in an available condition. When we use two or three hundred pounds per acre of a good artificial manure we in effect, directly or indirectly, convertpoor manure into rich manure. There is manure in our soil, but it is poor. There is manure in our barn-yard, but it is poor also. Nitrogen and phosphoric acid will make these manures rich. This is the reason why a few pounds of a good artificial manure will produce as great an effect as tons of common manure. Depend upon it, the coming farmer will avail himself of the discoveries of science, and will use more artificial fertilizers.
But whether we use artificial fertilizers or farm-yard manure, we shall not get the full effect of the manures unless we adopt a judicious rotation of crops.
When we sow wheat after wheat, or barley after barley, or oats after oats, we certainly do not get the full effect of the manures used. Mr. Lawes’ experiments afford conclusive evidence on this point. You will recollect that in 1846, one of the plots of wheat (10b), which had received a liberal dressing of salts of ammonia the year previous, was left without manure, and the yield of wheat on this plot was no greater than on the plot which was continuously unmanured. In other words,the ammonia which was left in the soil from the previous year, had no effect on the wheat.
The following table shows the amount of nitrogen furnished by the manure, and the amount recovered in the crop, when wheat is grown after wheat for a series of years, and also when barley is grown after barley, and oats after oats.
TABLE SHOWING THE AMOUNT OF NITROGEN RECOVERED, AND NOT RECOVERED, IN INCREASE OF PRODUCE, FOR 100 SUPPLIED IN MANURE.
100N:For 100 Nitrogen in Manure
R/I:Recovered in Increase.
NRI:Not Recovered in Increase.
Mixed Mineral Manure and 200 lbs. Ammonia-salts (= 41 lbs. Nitrogen)
Mixed Mineral Manure and 400 lbs. Ammonia-salts (= 82 lbs. Nitrogen)
Mixed Mineral Manure and 600 lbs. Ammonia-salts (= 123 lbs. Nitrogen)
Mixed Mineral Manure and 800 lbs.1Ammonia-salts (= 164 lbs. Nitrogen)
Mixed Mineral Manure and 550 lbs.2Nitrate Soda (= 82 lbs. Nitrogen)
Mixed Mineral Manure and 200 lbs. Ammonia-salts (= 41 lbs. Nitrogen)
Mixed Mineral Manure and 400 lbs. Ammonia-salts (= 82 lbs. Nitrogen) 6 years, 1852-’57
Mixed Mineral Manure and 200 lbs. Ammonia-salts (= 41 lbs. Nitrogen) 10 years, 1858-’67
Mixed Mineral Manure and 275 lbs. Nitrate Soda (= 41 lbs. Nitrogen) 4 years, 1868-’71
Mixed Mineral Manure and 2000 lbs. Rape-cake (= 95 lbs. Nitrogen) 6 years, 1852-’57
Mixed Mineral Manure and 1000 lbs. Rape-cake (= 47.5 lbs. Nitrogen) 14 years, 1858-’71
Mixed Mineral Manure and 400 lbs. Ammonia-salts (= 82 lbs. Nitrogen)
Mixed Mineral Manure and 550 lbs. Nitrate Soda (= 82 lbs. Nitrogen)
1. 13 years only, 1852-1864.
2. 475 lbs. Nitrate = 71 lbs. Nitrogen in 1852; 275 lbs. = 41 lbs. Nitrogen in 1853 and 1854; 550 lbs. = 82 lbs. Nitrogen each year afterwards.
It is not necessary to make any comments on this table. It speaks for itself; but it does not tell half the story. For instance, in the case of wheat and barley, it gives the average result for 20 years. It shows that when 100 lbs. of nitrogen in a soluble and available form, are applied to wheat, about 68 lbs. areleft in the soil. But you must recollect that 100 lbs. was applied again the next year, and no account is taken of the 68 lbs. left in the soil—and so on for 20 years. In other words, on plot 8, for instance, 2,460 lbs. of nitrogen have been applied, and only 775 lbs. have been recovered in the total produce of grain, straw, and chaff, and 1,685 lbs. have been left in the soil.
Mr. Lawes estimates, from several analyses, that his farm-yard manure contains 0.637 per cent of nitrogen, 2.76 per cent of mineral matter, and 27.24 per cent of organic matter, and 70 per cent of water.
According to this, the plot dressed with 14 tons of manure every year, for 20 years, has received 3,995 lbs. of nitrogen, of which 583¼ lbs. were recovered in the produce, and 3,411¾ lbs. were left in the soil.
In the case of barley, 3,995 lbs. of nitrogen was applied during the 20 years to the plot dressed with farm-yard manure, of which 427½ lbs. were recovered in the crop, and 3,567½ lbs. left in the soil.
“I see,” said the Deacon, “that barley gets less of the goodness out of farm-yard manure than wheat, but that it gets more out of the salts of ammonia and nitrate of soda. How do you account for that?”
“I suppose, because the manure for wheat was applied in the autumn, and the rains of winter and spring dissolved more of the plant-food than would be the case if the manure was applied in the spring. If the manure had been applied on the surface, instead of plowing it under, I believe the effect would have been still more in favor of the autumn-manuring.”
When the nitrogen is in an available condition, spring barley can take up and utilize a larger proportion of the nitrogen than winter wheat. Neither the wheat nor the barley can get at and take up half what is applied, and this, notwithstanding the fact that a heavy dew or a slight rain furnishes water enough on an acre to dissolve a liberal dressing of nitrate of soda or sulphate and muriate of ammonia. The truth is, the soil is very conservative. It does not, fortunately for us, yield up all its plant-food in a year.
We have seen that when wheat or barley is dressed with solubleammonia-salts or nitrate of soda, a considerable amount of the nitrogen is left in the soil—and yet this nitrogen is of comparatively little benefit to the succeeding crops of wheat or barley, while a fresh dressing of ammonia-salts or nitrate of soda is of great benefit to the crop.
In other words, when wheat is sown after wheat, or barley after barley, we do not get half the benefit from the manure which it is theoretically capable of producing.
Now, the question is, whether by a judicious rotation of crops, we can avoid this great loss of manure?
There was a time when it was thought that the growth of turnips enriched the soil. I have heard it said, again and again, that the reason English farmers grow larger crops of wheat and barley than we do, is because they grow so many acres of turnips.
“So I have often heard,” said the Deacon, “and I supposed the broad turnip leaves absorbed nitrogen from the atmosphere.”
There is no evidence that leaves have any such power; while there are many facts which point in an opposite direction. The following experiments of Lawes and Gilbert seem to show that the mere growth of turnips does not enrich land for grain crops.
Turnips were grown on the same land, year after year, for ten years. The land was then plowed and sown to barley for three years. The following table gives the results:
Hoos-Field—Barley, without manure, after 3 corn-crops
Barn-Field—Barley, after 10 yrs. Turnips manured as under—
1.—Mineral manures (last 8 years)
2.—Mineral manures (8 yrs.); Ammonia-salts (6 yrs.).
3.—Mineral manures (8 yrs.); Rape-cake (6 yrs.)
4.—Mineral manures (8 yrs.); Ammonia-salts and Rape-cake (6 yrs.)
5.—Mineral manures (8 yrs.); Ammonia-salts, for Barley, 1854
6.—Mineral manures (8 yrs.); Ammonia-salts, for Barley, ’54 and ’55
The yield of barley after turnips is less than it is after grain crops, and it is evident that this is due to a lack of available nitrogenin the soil. In other words, the turnips leavelessavailable nitrogen in the soil than grain crops.
After alluding to the facts given in the foregoing table, Messrs. Lawes and Gilbert say:
“There is evidence of another kind that may be cited as showing that it was of available nitrogen that the turnips had rendered the soil so deficient for the after-growth of barley. It may be assumed that, on the average, between 25 and 30 lbs. of nitrogen would be annually removed from the Rothamsted soil by wheat or barley grown year after year without nitrogenous manure. But it is estimated that from the mineral-manured turnip-plots there were, over the 10 years, more than 50 lbs. of nitrogen per acre per annum removed. As, however, on some of the plots, small quantities of ammonia-salts or rape-cake were applied in the first two years of the ten of turnips, it is, perhaps, more to the purpose to take the average over the last 8 years of turnips only; and this would show about 45 lbs. of nitrogen removed per acre per annum. An immaterial proportion of this might be due to the small amounts of nitrogenous manures applied in the first two years. Still, it may be assumed that about 1½ time as much nitrogen was removed from the land for 8, if not for 10 years, in succession, as would have been taken in an equal number of crops of wheat or barley grown without nitrogenous manure. No wonder, then, that considerably less barley has been grown in 3 years after a series of mineral-manured turnip-crops, than was obtained in another field after a less number of corn-crops.