At all events, there can be no doubt that wood-ashes would be very advantageous to bottom lands. And we are persuaded that such soils may be kept in wheat and corn for any length of time, if thus managed. In conclusion, corn your bottom-lands till they are too light, hogging instead of harvesting them; then put in wheat or oats; leave the stubble long, burn it over, and put it into wheat again, or to corn, as the case may be.
There are two opinions which will prevent any attempt to improve the cultivation of wheat, or, indeed, of anything else. The first is the opinion that, what are called _wheat-lands_, yield enough at any rate: the second is the opinion of those who own a soil not naturally good for wheat, that there is no use in trying to raise much to the acre. We suppose that wheat will not _average_ more than twelve bushels to the acre, as it is now cultivated in some parts. At that rate, and with too low prices, it is not worth cultivation for commercial purposes. The cost of seed, of labor in preparing the soil, putting in the crop, harvesting, threshing, and carrying it to market, is greater than the value of the crop. At fifty cents a bushel, and twelve bushels to the acre, the farmer gets six dollars, which certainly does not cover the worth of his time and the interest on his land.
Is it possible, then, at an expense within the means of ordinary farmers, to bring a double or treble crop of wheat? If nature has set limits to the produce of this grain to the acre, and if our farmers have come up to that limit, there is no use in their trying to do any better. But if their crop is four fold behind what it ought to be, they will feel courage to reach out for a better mode of cultivation. Vegetables collect food from the atmosphere, and from the soil; and different plants select different articles of food from the soil, just as different birds, beasts, insects, etc., require different food. One class of plants draws potash largely from the soil, as turnips, potatoes, the stalk of corn, etc. Another class requires lime, in great measure, as tobacco, pea straw, etc. Liebig partially classifies plants according to the principal food which they require; as silica plants, lime plants, potash plants, etc.