There is no doubt that the age of some fruit trees has much influence on the flavor of the fruit. This fact is quite in accordance with what might be assumed would be the case, judging from the laws of vegetable physiology; inasmuch as many of the secretions of plants are known to vary considerably, both in flavor and consistence, with the age of the plant.

In floriculture, even, the shape and colors of flowers are often found to alter to a certain extent, after the plants have attained some age, from those which they possessed as seedlings. Care, therefore, should be taken not to reject too hastily newly introduced varieties of fruits, whether imported kinds, or such as may be originated by those who are engaged in the interesting and praiseworthy occupation of endeavoring to add to the Pomological riches of their country.

Many years since, the writer had in his garden in England, a very old Green Gage plum tree, some fifteen or twenty feet in height, and, probably, eight or ten inches in diameter near the ground. It had but a moderate sized, straggling top of branches, but it bore fruit of remarkably fine quality. The plums were, however, very small, and but for their high flavor, would have been little valued.

This tree chanced to throw out a vigorous young shoot from the old stem, (which was perfectly sound and in good health,) and the idea presented itself, that it might be possible to add to the size of the fruit, by removing the top of the tree, and renewing it from this young branch. The stem of the tree was, therefore, cut through just above it in a slanting direction, and the whole strength of the roots being thereby thrown into the young branch, (then in the second year of its growth,) it made rapid progress; and in two years from that time, it commenced bearing, and well repaid the experiment; the size of the fruit was more than doubled, and the flavor retained all the excellence for which the tree had long been remarkable.

Some varieties of pears (upon their own roots) undoubtedly present the same phenomena. A tree of an old and highly esteemed pear in England, that was comparatively young, always bore fruit of very large size and shape, but of a mealy flavor; while an old tree of the same kind, similarly circumstanced as regards soil and situation, produced invariably fruit of high quality; evidently consequent only on the difference of age in the two trees: but the size of fruit was much in favor of the younger tree.

The renovation of old fruit trees deserves, also, more attention than it often receives. So long as a sufficient portion of the trunk remains sound, there are few old trees that can not be rendered valuable. If the variety be not really good, of course, it is worse than useless to retain it, and the tree must, therefore, either be cut down, or, if sound, grafted.

The causes of deterioration of old trees that are sound, but cease to bear, or that yield imperfect fruit, will generally be found to arise either from poverty of the soil, (its good qualities having been appropriated by the tree in bygone years,) or in the fact that the roots have penetrated too deeply into the subsoil. These evils may be remedied, by digging a trench round the tree at a distance from the trunk, at least equal to the spread of the branches; from this trench, and between the larger roots found near the surface, an approach may be made nearer towards the trunk of the tree, so as to cut through many of the roots that may be seen to grow downwards into the subsoil; and after that, the earth removed may be replaced, with a rich compost of fresh loam, and a little manure mixed with it.

An instance of the accidental restoration of a large pear tree, that had for many years been neglected, and which was supposed by the owner to be valueless, will illustrate the simple means by which such an operation may sometimes be effected. The tree was very old, and happened to stand within about ten yards of the back entrance to a large garden, which had formerly been kept in high order, but for many years subsequently had been but poorly cultivated.

In the fall of the year, a large quantity of old manure was purchased, for the purpose of improving the ground for vegetables. This manure was heaped up against and around the old pear tree some three or four feet high, simply because the place was convenient to the back entrance gate, and was, moreover, pretty much out of sight from the rest of the garden. The manure remained there through the winter, and in the spring was used up as required in the garden. In the following autumn, the tree (an old Bergamot pear) bore a very heavy crop of fruit, remarkable both for size and flavor. And thenceforth it continued (and possibly may yet continue) to yield a good annual crop. Of course, no one at all conversant with the subject, would recommend piling up manure against the stem of a tree. In this instance, it was done unwittingly by the men, and was again removed before it did harm; and, undoubtedly, without any intention of the tree being affected by it for good or ill.

The best method of keeping fruit in winter, is a subject on which the experience of fruit-growers, who are readers of the Horticulturist, would be acceptable. Some six or seven years ago, a gentleman of the name of Curtis, at Boston, was making experiments, which were said to promise well, and which he was to communicate to the Massachusetts Horticultural Society. Who knows what came of them?

Is there any better system of keeping apples and pears for use in the spring, than the old-fashioned one of enveloping each in paper in November, and stowing them away in boxes kept in a cool dry place, free from frost? Fifty years ago, that was the way they were kept in the old country (at least the choice table fruit) with success; but the trouble attending it where the quantity is considerable, precluded the adoption of the plan, except to a limited extent.

What is wanted, is a good system "for the million," as the saying is, in these go-ahead days. But that system does not seem to be yet forthcoming. Fruit rooms are expensive things "for the million," and even the right principles for constructing these, where expense is no obstacle, are not by any means reduced to such a state of accuracy as to lead to quite satisfactory results in the majority of cases.

In treating, or rather digesting the subject, it should be borne in mind, that the separation of the fruit from the tree does not destroy its vitality. It must not be regarded as a dead branch. It has no longer the power of growth or enlargement; but many of the meteorological influences which affected an apple or pear while hanging on the tree, will, in a modified degree, produce changes in them of a similar or analogous character for a greater or less time after they are gathered. These changes may be, and are, we know from experience, capable of being, within certain limits, hastened or modified by circumstances, as the temperature, moisture, dryness, and some other conditions of the atmosphere, by which they are surrounded.

This we all know; and, therefore, the question is, how to regulate these conditions to the best advantage with reference to the object in view, having regard to the fact that the vital agency is still operative; (which admits of demonstration as to some of the vital powers;) and it would seem, therefore, that success can only be attained by having due regard to that circumstance, whatever be the plan under experiment.

(The method of Mr. Curtis was, we believe, reported to the Massachusetts Horticultural Society, which awarded him a medal; but the mode itself has never been laid before the public that we are aware of. - Ed].