MANURES FOR OATS.
“What is the use of talking about manure for oats,” said the Deacon,
“if land is not rich enough to produce oats without manure, it certainly
will not pay to manure them. We can use our manure on some crop that
will pay better.”
“That is precisely what we want to know,” said I. “Very likely you are
right, but have you any evidence?”
“Evidence of what?”
“Have you any facts that show, for instance, that it will pay better to
use manure for wheat or barley than for oats?”
“Can’t say that I have, but I think manure will pay better on wheat than
on oats.”
Mr. Lawes is making a series of experiments on oats. Let us take a hasty
glance at the results of the first two seasons:
Experiments on Oats at Rothamsted.
----------------------------+-----------+-----------+------------
| Grain, in | Straw, |Weight per
| bushels. | cwts. |bushel, lbs.
Manures per Acre. +-----+-----+-----+-----+-----+------
| 1869| 1870| 1869| 1870| 1869| 1870
----------------------------+-----+-----+-----+-----+-----+------
1.--No manure | 36⅝ | 16⅜ | 19¼ | 9⅛ | 36¾ | 35
2.--Mixed Alkalies and | | | | | |
Superphosphate of Lime | 45 | 19⅛ | 24½ | 9⅝ | 38½ | 35⅛
3.--400 lbs. Ammonia-salts | 56⅛ | 37½ | 36⅞ | 17¼ | 37½ | 34¼
4.--Mixed Alkalies and | | | | | |
Superphosphate, and 400 | | | | | |
lbs. Ammonia-salts | 75¼ | 50⅝ | 54 | 28⅝ | 39¼ | 36
5.--550 lbs. Nitrate of Soda| 62¼ | 36½ | 42¾ | 23 | 38½ | 35¼
6.--Mixed Alkalies, | | | | | |
Superphosphate, and 550 | | | | | |
lbs. Nitrate of Soda | 69⅜ | 50 | 49⅞ | 28¾ | 38½ | 35¾
----------------------------+-----+-----+-----+-----+-----+------
It seems clear that, for oats, as for barley and wheat, what we most
need in manure, is available nitrogen.
The first year, the no-manure plot produced 36⅝ bushels of oats per
acre, weighing 36¾ lbs. per bushel, and plot 3, with ammonia-salts
alone, 56⅛ bushels, and with nitrate of soda alone, on plot 5, 62¼
bushels per acre, both weighing 38½ lbs. per bushel. In other words, 82
lbs. of available nitrogen in the salts of ammonia gave an increase of
about 20 bushels per acre, and the same quantity of nitrogen in nitrate
of soda an increase of 26 bushels per acre.
The next year, the season seems to have been a very unfavorable one for
oats. The no-manure plot produced less than 17 bushels per acre; and the
“ashes” and superphosphate on plot 2, give an increase of less than 3
bushels per acre. But it will be seen that on plot 3 the ammonia-salts
do as much good in this unfavorable season as in the favorable one. They
give an increase of over 20 bushels per acre.
“A few such facts as this,” said the Deacon, “would almost persuade me
that you are right in contending that it is in the unfavorable seasons,
when prices are sure to be high in this country, that a good farmer
stands the best chance to make money.”
“Where mixed alkalies and superphosphate,” said the Doctor, “are added
to the ammonia, the increase _from the ammonia_ is far greater than
where ammonia is used alone. In other words, by comparing plot 2 and
plot 4, you will see that the ammonia gives an increase of 30¼ bushels
per acre in 1869, and 31½ bushels in 1870.”
The truth of the matter probably is this: 100 lbs. of available ammonia
per acre is an excessive supply, when used alone. And in fact Mr. Lawes
himself only recommends about half this quantity.
Whether it will pay us to use artificial manures on oats depends on the
price we are likely to get for the oats. When the price of oats _per
lb._ and oat-straw is as high as barley and barley-straw _per lb._, then
it will pay a _little better_ to use manure on oats than on barley. As a
rule in this country, however, good barley is worth more per lb. than
good oats; and it will usually pay better to use artificial manures on
barley than on oats.
Some years ago Mr. Bath, of Virginia, made some experiments on oats with
the following results:
Bushels of oats
per acre.
No. 1--200 lbs. Superphosphate 22
No. 2--200 lbs. Peruvian guano 48¾
No. 3--100 lbs. Peruvian guano 32
The oats were sown March 13, and the crop harvested July 4.
In 1860, I made some experiments with gypsum, superphosphate, and
sulphate of ammonia as a top-dressing on oats.
The land was a clover-sod, plowed about the middle of May, and the oats
sown May 20. On the 26th of May, just as the oats were coming up, the
manures were sown broadcast. The oats were sown too late to obtain the
best results. On another field, where the oats were sown two weeks
earlier, the crop was decidedly better. The oats were cut August 28.
The following is the result:
Experiments on Oats at Moreton Farm, Rochester, N.Y.
------+----------------------------------+--------+-------+--------
| |Bushels |Weight/| Straw
Plots.| Manures per Acre. |of Oats/|Bushel |per acre
| |acre. |in lbs.| in lbs.
------+----------------------------------+--------+-------+--------
No. 1 |No manure | 36 | 22 | 1,958
2 |600 lbs. Gypsum (Sulphate of Lime)| 47 | 26 | 2,475
3 |300 lbs. Superphosphate of Lime | 50 | 21 | 2,475
4 |300 lbs. Sulphate of Ammonia | 50 | 22 | 2,730
5 |300 lbs. Superphosphate of Lime, | | |
| and 300 lbs. Sulphate of Ammonia| 51 | 22½ | 2,575
------+----------------------------------+--------+-------+--------
These experiments were made when my land was not as clean as it is now.
I presume the weeds got more benefit from the ammonia than the oats. To
top-dress foul land with expensive artificial manures is money thrown
away. If the land had been plowed in the autumn, and the seed and
manures could have been put in early in the spring, I presume we should
have had more favorable results.
“Are you not ashamed to acknowledge,” said the Deacon, “that you have
ever raised oats weighing only 22 lbs. per bushel.”
No. I have raised even worse crops than this--and so has the Deacon. But
I made up my mind that such farming did not pay, and I have been trying
hard since then to clean my land and get it into better condition. And
until this is done, it is useless to talk much of artificial manures.
The most striking result is the effect of the gypsum. It not only
gave an increased yield of 11 bushels per acre, but the oats were of
decidedly better quality, and there was nearly half a ton more straw per
acre than on the plot alongside, where no manure was used.
The superphosphate was a good article, similar to that used in Mr.
Lawes’ experiments.