The precise point or elevation point at which this heading-back should be done, will depend very much upon the object of the cultivator, and whether he desires to produce a high or a low head, a standard, half standard, or a dwarf, or conical tree--such as are often called pyramids. He will study the wants and fancies of his customers in this matter, but we of the West, have learned the importance for us, at least, of _trimming our trees down_, and not trimming them up, as is often done by those who anticipate plowing and planting crops under the shade of their orchards. The proper point for forming the branches to make the head, will very much depend, however, upon the habit of the variety; whether it be drooping, spreading, or upright. The former will require the branches to be started at a higher point. The proper season for performing this kind of pruning is in the early spring, or after the severe frosts of winter have passed; and with some kinds of orchard trees, it may be done at the time of transplanting them, when they need a severe pruning. The second object of pruning being done with a view to the production of fruitfulness in the tree, is to be practised chiefly in the summer. At the same time, or during the growing season, much may be done to advantage, both in thinning-out and shortening-in such parts of the tree, as may need these plans of treatment. Various methods are pursued to produce fruitfulness, all of them depending upon the fact that this condition arises from the natural habit of a tree to make its wood-growth freely for a series of years. After it has built up a complicated structure of limbs and branches, with some consequent obstruction to the flow of sap, depending upon the hardening of the woody tissues, and the tortuous course of its circulation, it then appears to have reached its maturity, or its fruit-bearing condition. It then ceases to make such free wood-growth, and prepares a set of buds, which develop flowers and fruit. Now this period of growth and unfruitfulness may continue for a longer or shorter time in different varieties of fruits; and the shortening of this, is the great object of summer pruning, and of other methods of producing fruitfulness that may be classed under this second head of the objects of pruning.