“Again, in the opinion of several good, practical agriculturists, with whom I have conversed on the subject, land whereon clover has been grown for seed in the preceding year, yields a better crop of wheat than it does when the clover is mown twice for hay, or even only once, and afterwards fed off by sheep.”
“I do not think,” said the Deacon, “that this agrees with our experience here. A good crop of clover-seed is profitable, but it is thought to be rather hard on land.”
“Such,” said I, “is the opinion of John Johnston. He thinks allowing clover to go to seed, impoverishes the soil.”
Charley, continued to read:
“Whatever may be the true explanation of the apparent anomalies connected with the growth and chemical history of the clover-plant, the facts just mentioned, having been noticed, not once or twice only, or by a solitary observer, but repeatedly, and by numbers of intelligent farmers, are certainly entitled to credit; and little wisdom, as it strikes me, is displayed by calling them into question, because they happen to contradict the prevailing theory, according to which a soil is said to become more or less impoverished, in proportion to the large or small amount of organic and mineral soil constituents carried off in the produce.”
“That is well said,” I remarked, “and very truly; but I will not interrupt the reading.”
“In the course of a long residence,” continues Dr. Vœlcker, “in a purely agricultural district, I have often been struck with the remarkably healthy appearance and good yield of wheat, on land from which a heavy crop of clover-hay was obtained in the preceding year. I have likewise had frequent opportunities of observing, that, as a rule, wheat grown on part of a field whereon clover has been twice mown for hay, is better than the produce of that on the part of the same field on which the clover has been mown only once for hay, and afterwards fed off by sheep. These observations, extending over a number of years, led me to inquire into the reasons why clover is specially well fitted to prepare land for wheat; and in this paper, I shall endeavor, as the result of my experiments on the subject, to give an intelligible explanation of the fact, that clover is so excellent a preparatory crop for wheat, as it is practically known to be.
“By those taking a superficial view of the subject, it may be suggested that any injury likely to be caused by the removal of a certain amount of fertilizing matter, is altogether insignificant, and more than compensated for, by the benefit which results from the abundant growth of clover-roots, and the physical improvement in the soil, which takes place in their decomposition. Looking, however, more closely into the matter, it will be found that in a good crop of clover-hay, a very considerable amount of both mineral and organic substances is carried off the land, and that, if the total amount of such constituents in a crop had to be regarded exclusively as a measure for determining the relative degrees in which different farm crops exhaust the soil, clover would have to be described as about the most exhausting crop in the entire rotation.
“Clover-hay, on an average, and in round numbers, contains in 100 parts:
| Water | 17.0 |
| Nitrogenous substances, (flesh-forming matters)* | 15.6 |
| Non-nitrogenous compounds | 59.9 |
| Mineral matter, (ash) | 7.5 |
| 100.0 | |
| * Containing nitrogen | 2.5 |