such a way that the long-lived trees will become useful about the time the short-lived trees reach maturity. The latter can then be removed, leaving the ground to the long-lived trees. In all cases an ultimate stand of such trees as elms, oaks, walnuts, or chestnuts should be the aim.
It may seem that the number of kinds that may be used for school ground planting is small, but this is not the case. In almost all sections of the country, a long list of species fully adapted to the purpose can be made out. In selecting among these the aim should be to give the plantation as much variety as possible, since among other purposes it is to serve that of instruction.
OBTAINING THE TREES.—In many places trees can be obtained from the neighboring forests, from the banks of streams, from plantations, or even from open fields. If they have had normal conditions of growth and are taken at the right time, they are almost as valuable for planting as nursery-grown seedlings. Pines, spruce and cedar are to be collected in unlimited numbers in many forests, and frequently ash, maple and elm are almost as abundant. They may be gathered either in the fall of spring, but unless they are very carefully heeled in and protected over winter the better time is early spring. In collecting forest seedlings only the small trees that have grown in the light should be taken, as these are more likely to be young and vigorous than those grown in the shade. The collector should never pull the trees from the ground, but should dig them carefully with a spade, preserving as much of the root as possible.
TIME AND MANNER OF PLANTING.—South of the thirty-seventh parallel, fall planting is safe and often advantageous. North of this, spring planting should be the rule, as fall planted trees can scarcely develop sufficient roots to sustain themselves during the winter. The most successful nurserymen practice early planting for deciduous trees, beginning operations as soon as the ground ceases freezing. Evergreens are not planted until later; some even wait until the young growth is starting. If possible, planting should be done on a cool, cloudy day. Unless the day is very moist, the trees should be carried to the planting site in a barrel half filled with water, or a thin mixture of earth and water, and lifted out only as they are wanted. Even a minute's exposure to dry air will injure the delicate roots—the feeders of the tree.
The roots should be extended in their natural positions and carefully packed in fine loam soil. It is a good practice to work the soil about each root separately and pack it solid with the foot. As the hole is filled the earth should be compacted above the roots and around the stem, in order to hold the tree firmly in the place. The last two inches of soil should be very fine, and should lie perfectly loose. It will serve as a mulch to retain the moisture.
Trees should be planted neither in very wet nor in very dry soil. If the soil is wet, it is better to wait until it is dryer. On the other hand, if good cultivation has been maintained the year previous to the
