Believing your valuable periodical is extensively circulated through the Southern States, I desire making it the medium through which to give some hints upon fruit-culture that I deem of importance in this latitude.

The observant frequently notice the bark upon the stems of trees, and especially the apple, perforated with numerous holes, sometimes of sufficient size to admit the moisture and encourage decay. What causes these holes, and how arc we to prevent their formation?

In order to discover a remedy we must consider the manner in which they are formed.

These holes are first made by worms, and enlarged by birds in search of the grubs. The grub is hatched from eggs deposited under the shaggy bark so frequent upon the stems of fruit trees. This rough and half disconnected bark is the result of an inactive circulation of sap; the same as the hand becomes callous by constantly grasping some hard substance, and interfering with the free circulation of blood. This imperfect circulation of sap, I think, is the result of training the trees with too long stems:

If the trunk of the tree is too long, the top does not protect it from the sun's rays. While the sap is ascending from the roots into the top, a considerable portion of its aqueous substance evaporates through the bark, leaving the remainder thick. The sap vessels become filled with a gummy substance which obstructs the free circulation, and causes the rough, hard bark to accumulate.

As the tree increases in age and size, this hard bark forms a perfect shell around it which greatly impedes the free circulation, especially when the sap is in the condition above mentioned. If the tree possesses, a sufficiently vigorous constitution to continue growing, it will burst this shell, if not, it will struggle along for several years and finally die. After the increase of the stem has forced this hard bark to crack, the sun causes it to warp up, forming scales, and affording excellent places of refuge for insects to deposit their eggs.

If trees are trained with low heads there will be no stem, or at least not much to become diseased, or for insects to prey upon. The top will shade the stem and roots; keep up a greater equilibrium in the temperature of the soil; guard against drouth; admit of an active circulation; and by saving the constituents of water, which would, to a certain extent, be lost by evaporation if compelled to ascend through a long unprotected stem, afford the fruit a greater proportion of hydrogen, an element which exerts a great influence over the flavor of the fruit.

That disease known as the frozen sap blight, and so destructive to pear-trees in this vicinity, is more prevalent in seasons succeeding a warm and late fall, terminating with a sudden freezing. The disease I consider is caused as follows: The late warm weather peculiar to this climate some seasons, recommences an active circulation late in the fall, which fills the sap vessels with aqueous substances, and more particularly the young and topmost branches. The rapidity with which cold weather commences does not afford sufficient time for the watery substances within these branches to either enter into the formation of woody fibre or pass off by evaporation, consequently remains within them as such, and when frozen increases in volume, tears the sap vessels, and establishes a disease which makes its appearance the following spring.

If the tree had been trained with a short stem, the top with its cooling shade would not have permitted the soil to become sufficiently warm to excite the tree into a late growth; circulation would have ceased, and the leaves have dropped off at an earlier period in the season; the new growth would have had sufficient time to attain some degree of solidity, and the tree would be free from all danger of frozen sap blight.

It is frequently observed that dwarf pear-trees are comparatively free from this disease.

This peculiarity is very easity explained when we consider they are not only trained with short stems, but by being worked upon the quince, discontinue growth sufficiently early in the season to admit of the watery substance, either entering into the formation of woody fibre, or to pass off by evaporation, thereby affording sufficient time for the new wood to become able to withstand the vicissitudes of the weather.

The benefits the tree derives from a low head are quite as perceptible -in the spring as in the fall, as the shade produced by the top retards the period of blossoming, and frequently prevents the fruit from being destroyed by late frosts.

The length of the. stem also increases the danger of having the fruit I blown off, in which case the fall is sufficiently great to render it worthless.

The force of the wind against the top, by acting upon the lever principle, causes a great strain upon the roots, often displacing or breaking them, and frequently overturning the tree. If the stem is sufficiently long to admit of its bending, the sap vessels on the outer side of the curve will be forced to expand, while those on the inside will contract. Both positions being unnatural extremes, exerts a ruinous influence upon the health and longevity of the tree.

Many persons object to low-headed trees as they do not admit of ploughing underneath the branches. If they would consider tearing up the soil, and bruising or breaking the roots immediately near the stem, in a manner so frequent among orchardists, they would not only discover they were destroying the facilities of the tree for obtaining sufficient aliment to mature properly, - even a medium crop of fruit, - but injuring the surface roots upon which the tree is greatly dependant for a large proportion of the animal and vegetable matter essential for its formation.

While cultivating fruit-trees at the South, I have permitted the following rules to direct my operations. My success thus far has exceeded my own sanguine expectations.

1st. Get good healthy Southern raised trees, of such varieties as require the conditions peculiar to a warm climate for their perfect development.

2d. Plant them on fertile land, and keep the soil in good condition.

3d. Train the trees with short stems. Two feet in height is sufficient for standards.

4th. Brush off all superfluous shoots while small, and never let a branch grow unless wanted.

5th. Trust the remainder to Providence, and my word for it, you will have fruit.