Protection of the roots from drying is the chief precaution to be observed during the planting process, and for this reason a cloudy day is preferable to a sunny day for planting.  In case of evergreens, the least exposure of the roots is liable to result disastrously, even more so than in case of deciduous trees.  This is why evergreens are lifted from the nursery with a ball of soil around the roots.  All bruised roots should be cut off before the tree is planted, and the crown of the tree of the deciduous species should be slightly trimmed in order to equalize the loss of roots by a corresponding decrease in leaf surface.

The tree should be set into the tree hole at the same depth that it stood in the nursery.  Its roots, where there is no ball of soil around them, should be carefully spread out and good soil should be worked in carefully with the fingers among the fine rootlets.  Every root fibre is thus brought into close contact with the soil.  More good soil should be added (in layers) and firmly packed about the roots.  The last layer should remain loose so that it may act as a mulch or as an absorbent of moisture.  The tree should then be thoroughly watered.

[Illustration:  FIG. 95.—­Specifications for a Street Tree.]

After care:  During the first season the tree should be watered and the
    soil around its base slightly loosened at least once a week,
    especially on hot summer days.  Where trees are planted on streets,
    near the curb, they should also be fastened to stakes and protected
    with a wire guard six feet high.  See Fig. 95.  Wire netting of
    1/2-inch mesh and 17 gauge is the most desirable material.

[Illustration:  FIG. 96.—­A Home Nursery. (Austrian pines in front.)]

Suggestions for a home or school nursery:  Schools, farms, and private
    estates may conveniently start a tree nursery on the premises and
    raise their own trees.  Two-year seedling trees or four-year
    transplants are best suited for this purpose.  These may be obtained
    from several reliable nurseries in various parts of the country that
    make a specialty of raising small trees for such purposes.  The cost
    of such trees should be from three to fifteen dollars per thousand.

The little trees, which range from one to two feet in height, will be shipped in bundles.  Immediately upon arrival, the bundles should be untied and the trees immersed in a pail containing water mixed with soil.  The bundles should then be placed in the ground temporarily, until they can be set out in their proper places.  In this process, the individual bundles should be slanted with their tops toward the south, and the spot chosen should be cool and shady.  At no time should the roots of these plants be exposed, even for a moment, to sun and wind, and they should always be kept moist.  The little trees may remain in this trench for two weeks without injury.  They should then be planted out in rows, each row one foot apart for conifers and two feet for broadleaf trees.  The individual trees should be set ten inches apart in the row.  Careful weeding and watering is the necessary attention later on.

CHAPTER VI