These are the natural enemies of fruits and plants; and to prevent their depredations requires much care. There is no universal remedy. Birds and young fowls--especially ducks and chickens--are useful in a garden. The ducks must not be kept there too long. They will appropriate a little to their own use, but will save much more for the proprietor. Insects have their peculiar tastes for particular fruits and plants, of which we have treated, under those heads, respectively. Success in many branches of horticulture and pomology, depends upon attention to the habits of insects. The most general remedy is to wash trees or plants with a strong decoction of some offensive herb, or with whale-oil soapsuds. Tobacco is very useful for this purpose. IRON FILINGS. It has been ascertained by analysis, that iron enters largely into the composition of the pear. Iron filings spread under them, or worked into the soil, increases the growth of pear-trees, and improves the quality of the fruit. IRRIGATION. This is one of the most important matters, that can engage the attention of agriculturists of the present day. A stream of water that may be caused to flow gently over a field, or different parts of a farm, at pleasure, is a mine of wealth. Plants receive their food from the air and water. We shall discuss this more fully when treating of manures. A poor, porous, sandy, or gravelly soil usually produces a fine crop, in a wet season. That is an addition to the soil of nothing but water. Hence all springs and streams can be turned to great account, on a farm or garden. Watering gardens by hand or with a garden-pump, will often pay better than any other expenditure on the land. Employing a man, in a dry season, to spend his whole time in watering five acres of garden, of berries and vegetables, as cabbages, vines, onions, and potatoes, will pay a very large profit. Strawberries will bear twice as much and twice as long, for daily watering, after they begin to bud for blossoms, until the fruit is gone. It is a necessary caution not to water irregularly, and only occasionally, in a dry season. Better not commence than to leave off, or neglect it in a dry time, before a rain. Read further in our article on "Watering." LABELS. It is important, on many accounts, to have fruit-trees and shrubs well labelled. Many labels have been invented. We prefer Cole's, as given in his Fruit Book, to any other. Take a piece of sound pine or other soft wood, whittle two sides smooth, leaving one wider than the other, with a sharp corner between them. For one, cut one notch in the edge, and so up to four, four notches for four. For five, cut across the narrow side. For ten cut across the wide side, and a notch for every ten up to forty. For fifty, cut obliquely across the narrow side, and for one hundred cut obliquely across the wide side. Keep the names in a book, with numbers corresponding with the notches or numbers on the labels.