_Windbreaks and screens._

A shelter-belt for the home grounds is often placed at the extreme edge of the home yard, toward the heaviest or prevailing wind. It may be a dense plantation of evergreens. If so, the Norway spruce is one of the best for general purposes in the northeastern states. For a lower belt the arbor vitae is excellent. Some of the pines, as the Scotch or Austrian, and the native white pine, are also to be advised, particularly if the belt is at some distance from the residence. As a rule, the coarser the tree the farther it should be placed from the house.

The common deciduous trees of the region (as elm, maple, box-elder) may be planted in a row or rows for windbreaks. Good temporary shelter belts are secured by poplars and large willows. On the prairies and far north the laurel willow _(Salix laurifolia_ of the trade) is excellent. Where snow blows very badly, two lines of breaks may be planted three to six rods apart, so that the inclosed lane may catch the drift; this method is employed in prairie regions.

Persons may desire to use the break as a screen to hide undesirable objects. If these objects are of a permanent character, as a barn or an unkempt property, evergreen trees should be used. For temporary screens, any of the very large-growing herbaceous plants may be employed. Very excellent subjects are sunflowers, the large-growing nicotianas, castor beans, large varieties of Indian corn, and plants of like growth. Excellent screens are sometimes made with vines on a trellis.

Very efficient summer screens may be made with ailanthus, paulownia, basswood, sumac, and other plants that tend to throw up very vigorous shoots from the base. After these plants have been set a year or two, they are cut back nearly to the ground in winter or spring, and strong shoots are thrown up with great luxuriance during the summer, giving a dense screen and presenting a semi-tropical effect. For such purposes, the roots should be planted only two or three feet apart. If, after a time, the roots become so crowded that the shoots are weak, some of the plants may be removed. Top-dressing the area every fall with manure will tend to make the ground rich enough to afford a very heavy summer growth. (See Fig. 50.)