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.