The theoretical objections to root grafts have yielded to sound philosophy, based on and supported by practical observation. The very many advantages of this more economical and convenient and agreeable process, will necessarily sustain root-grafting in this fast age, when so many millions of trees are needed for the rapidly extending wants of this nation of tree planters. We may, however, consider some of the practical objections which have been brought forward against this plan of multiplying the apple. In our very changeable climate, and particularly in the North-west, upon the prairies, the cold of winter often supervenes with great suddenness, after the young trees have made a prolonged and vigorous growth in the fertile soil, and produces terrible devastation among those that are there exposed, without protection of any kind, to the rude blasts of the storm-king: in a less degree, injury is very frequent with many such late-growing kinds, at the first access of a severe frost; this is manifested in the bursting of the bark near the base of the stem. The same thing is not so often seen in the same varieties, when they have been budded or stock grafted a foot or more from the ground upon hardy seedling stocks, hence judicious propagators have selected the "tender" varieties for this kind of working, and confine their root-grafting to those less liable to the injury. There are other varieties which do not readily and promptly form a strong upright growth, so as to be profitable trees to the nurseryman if root grafted; these are selected for stock working, either on strong seedlings, or upon hardy upright sorts that have been root grafted for the purpose of being thus double-worked. This plan has been pursued to a limited extent only, but its advantages in the production of good trees of the slender growing varieties, begin to be appreciated, and as the demand increases, our intelligent nurserymen will very soon furnish the requisite supply. _Planting._--When the weather is fine, and the soil in good condition, the root-grafts are to be set out with a dibble, by the line; they should be planted rather deeply, one bud projecting above the surface of the ground. The culture must be thorough, the plants should be kept perfectly clean, but it is questionable whether the growth should be pushed, late in the season; indeed, it is preferable to check the vegetation at mid-summer. For this purpose it has been recommended to cease cultivating the soil, or even to sow the ground with a heavy seeding of oats, so as to check the growth before winter. In good soils, with good culture, the average hight in the rows will be two feet, but there is a great difference in the kinds; some will considerably exceed this hight. Intelligent nurserymen no longer endeavor to have an excessive growth in the first year, and many prefer the bedding plan above alluded to.