When old pastures are broken up and made arable, not only has the soil been enriched by the death and slow decay of the plants which have left soluble matters in the soil , but the leaves and roots of the grasses living at the time and occupying so large a part of the surface, afford saccharine, mucilaginous, and extractive matters, which become immediately the food of the crop, and the gradual decomposition affords a supply for successive years.
Dry Straw of wheat, oats, barley, beans, and peas, and spoiled hay, or any similar kind of dry vegetable matter, is in all cases, useful manure. In general such substances are made to ferment before they are employed, though it may be doubted whether the practice should indiscriminately be adopted.
When straw is made to ferment it becomes a more manageable manure ; but there is likewise^ on the whole, a great loss of nutritive matter. More manure is supplied for a single crop; but the land is less improved than it would be, supposing the whole of the vegetable matter could be finely divided and mixed with the soil.
It is usual to carry straw that can be employed for no other purpose, to the dunghill, to ferment and decompose ; but it is worth experiment, whether it may not be more economically applied when chopped small by a proper machine and kept dry till it is ploughed in for the use of a crop. In this case, though it would decompose much more slowly and produce less effect at first, yet its influence would be much more lasting.
" Wood-ashes imperfectly formed, that is wood ashes containing much charcoal, are said to have been used with success as a manure. A part of their effects may be owing to the slow and gradual consumption of the charcoal, which seems capable under other circumH