Differences of opinion have prevailed, and discussions have taken place, as to the relative efficacy of long and short—or of half fermented and of fully rotten dung. But if it be added _solely_ for the purpose of yielding food to the plant, or of preparing food for it, the case is very simple. The more complete the state of fermentation—if not carried too far—the more immediate will be the agency of the manure; hence the propriety of the application of short dung to turnips and other plants it is desirable to bring rapidly forward; but if the manure be only half decayed, it will require time in the soil to complete the decomposition, so that its action will be more gradual and prolonged. Though in the latter case the immediate action is not so perceptible, yet the ultimate benefit to the soil, and to the crops, may be even greater, supposing them to be such as require no special forcing at one period of the year. With a view to this slow amelioration, vegetable matter of any kind may be added with benefit, if in a sufficient state of division, to the soil. Even saw-dust applied largely to the land, has been found to improve it, though little at first, yet more during the second year after it was applied, still more during the third, and most of all in the fourth season after it was mixed with the soil. That any dry vegetable matter, therefore, does not produce an immediate effect, ought not to induce the practical farmer to despise the application to his land—either alone, or in the form of a compost—of every thing of the kind he can readily obtain. If his fields are not already very rich in vegetable matter, both he and they are likely to be ultimately benefitted by such additions to the soil. _Rape Dust._—It is from the straw of the corn-bearing plants, or from the stems and leaves of the grasses, that the largest portion of the strictly vegetable manures applied to the soil is generally obtained or prepared. But the seeds of all plants are much more enriching than the substance of their leaves and stems. These seeds, however, are in general too valuable for food to admit of their application as a manure. Still the refuse of some, as that of different kinds of rape-seed after the oil is expressed, and which is unpalatable to cattle, is applied with great benefit to the land. Drilled in with spring wheat, or scattered as a top-dressing in spring at the rate of 5 cwt. to an acre, it gives a largely increased and remunerating return. It is applied with equal success to the cultivation of potatoes, and generally it may be substituted for farm-yard manure at the rate of about 1 cwt. of rape dust for each ton of manure. _Malt Dust_ consists of the dried sprouts of barley, which, when the sprouted seed is dried in the process of malting, break off and form a coarse powder. This is found to be almost equal to rape dust in fertilizing power.