Shade Trees In City Streets

Shade Trees In City Streets.

Garden and Forest
Vol VI, No. 259. Feb. 8, 1893. Pp. 70-71.
Meetings of Societies.
The Western New York Horticultural Society. – II.

The report of this meeting, which was begun last week, is continued below. Mr. William McMillan, Superintendent of Parks in Buffalo, in his usual vigorous manner, read a paper entitled.

SHADE-TREES IN CITY STREETS.

Shade-trees along the borders of the streets were at one time a distinguishing feature of American cities, and this city of Rochester is a good exemplar of the practice to-day. Perhaps no city in the country has had equal advantages in soil, subsoil, natural drainage, tree-supply, good example and public spirit. If in summer we take a bird’s-eye view of the town from the outlook pavilion in Highland Park, the houses seem to be nearly all hidden by the trees. The section where trees have given way to business is probably smaller than in any other city of its size.

In nearly all our cities street-trees are set out and cared for solely by the owner or the occupiers of the abutting property. Each man plants or not according to his own taste or interest in the matter. This involves much diversity and incongruity in the selection of species, in age and size, in the distance from the curb-line and from each other. Uniformity in these respects can only be obtained for any given stretch of street where the work is done by municipal authority. This method has been eminently successful in the leading cities of Europe, and in Washington, where nearly every street that has been opened and graded has been systematically planted under the central authority of a special commission.

Few persons realize the constant liability to damage and destruction to which young trees are exposed. Some idea of it may be gained by inspecting the trees on any given street and noting how few show no signs of stunted growth, scarred trunk, mutilated top, or blemish of some kind. The most common damage is the gnawing of the bark by horses, or of the branches, if within reach, but up to a certain age mischievous boys are far more destructive. If the sapling gets safely out of its swaddling-clothes it is next attacked at the roots by trenches for sewers, gas-pipes, water-pipes and electric cables, or by changes of lines or grades in laying curb-stones, or flagging. In later years the largest limbs will be mutilated by telegraph line-men and their wires. Again, under ordinary conditions the trees suffer constantly from lack of moisture, because the pavement or the beaten ground sheds most of the rainfall; from lack of food, because the roots cannot penetrate the hardened subsoil; from poison by gas, because the small service pipes soon become rusted through; and from want of air, because the soot and dust of the city stops up the pores of the leaves. The unhealthy condition resulting from these and other causes invites grubs and borers, slugs and caterpillars, scale, spider and fungal blight, all in great profusion. In the streets these insect pests are safe from their natural enemies, the birds, and from the poisonous spray of the gardener’s syringe.

The trees most commonly used are probably the best under average conditions. “Nothing succeeds like success,” and the points contributing most to this success are ease of propagation, cheapness of nursery culture, quickness of early growth, endurance under careless transplanting, average good looks and absence of bad habits, the ability to pick up a living on a scanty diet, and patience under abuse of every sort.

After explaining the merits and defects of the various Elms, Maples, Lindens, Ashes, Beeches and several other trees, Mr. McMillan continued: Oaks require early transplanting and extra care for a long time. But, in any city, where they can be securely protected until of good size, they endure the ordinary street conditions as well as Elms and Maples. Once well established, a Black, Red or Scarlet Oak will grow as fast as the average of other street-trees. The habit is always good; pruning or thinning of the branches is rarely necessary, and the glossy foliage is a special attraction all through the season.

But for foliage-effect, the finest trees are the Tulip and the Plane. Fine examples of each are occasionally seen in our streets, but general experience seems to condemn them. The soft roots of the Tulip-tree make it impatient of careless transplanting, unless very young, and protection from severe frosts is necessary in clay soils until the roots get below the frost line. But once well-established in any favorable soil and subsoils, it becomes a noble street tree, well worth any extra care bestowed on it. The Plane-tree is as easily transplanted as any Maple, and, if in good soil, its growth for many years is as rapid as that of the Poplar or Willow. But mature trees are so subject to serious fungus-blight that a healthy, clean-branched tree is rarely seen. In spite of these defects, both Tulip and Plane trees deserve persistent trial and experiment.

Fifty years ago, during the Silkworm craze, the Chinese Ailanthus was extensively planted in the eastern cities. Its rank growth, sub-tropical aspect, exemption from insects, and its fresh foliage in spite of prolonged heat or drought, made it very popular. Then came a reaction, so strong that the tree is now virtually tabooed, all apparently because the flowers have an unpleasant odor. But no tree has withstood so persistently the onslaught of all the destructive influences of a crowded street. Where the subsoil is porous its roots penetrate to an extraordinary depth, and thus find food enough under the closest pavements, and moisture enough during the longest droughts. There is a place for the Ailanthus in every large city, and that, if you give it no other, is the place where no other tree will thrive.

Americans despise “the day of small things.” This national foible is always prominent in the selection of trees for street planting. The general practice is to procure the largest trees that can be obtained and conveniently handled. If nurserymen cannot or will not furnish them of suitable size, they are procured from the neighboring woods if possible. It is surprising and mortifying to every experienced grower of trees, to see each spring the numerous wagon-loads which countrymen bring in from swamps and thickets, and expose for sale in our streets day after day with little or no protection from sun and wind. They are usually much larger than the most overgrown nursery stock, and the younger saplings twice or thrice the height becoming to their age, but they are bought in preference to the nurserymen’s “small fry.” The only roots are a few stout prongs, and they are set out in the smallest holes that will admit them, with the tree tops left unpruned or entirely chopped off. They remain standing like bean-poles for one or more years. Then they are pulled out, and other bean-poles stuck in their places. It is said “experience teaches fools,” but on this subject they need many years of schooling, else the class always under instruction would not be so large. Trees grown in nurseries have needful qualities of root, stem and branch, entirely lacking in the spindling sapling that has struggled for life and light in a shady thicket. But, of course, after being planted, the smaller the tree the greater the risk of serious damage by accidents that would be trifling to one of twice or thrice the size. This argument is the clincher in all discussions on this point. For this reason Elms, Maples, Horse-chestnuts, Poplars and Lindens are commonly preferred, as they can be successfully transplanted of a much larger size than Tulip-trees, Oaks or any of the nut-bearing trees. Yet the rule holds good, even in street planting, that whatever kinds of trees may be selected, the youngest that can be protected with a reasonable chance of safety ought to be preferred.

A common error is planting too near the curb-line and too close together in the row. Any young tree within four feet of the curb is ten times more likely to be gnawed by horses than one twice as far back. The roots also should be considered and given a fair chance to spread on all sides. Ample distance apart contributes not only to the health and symmetry of the tree, but also allows a pleasant play of sunshine and breeze to the people on the street. Close planting may look best for a few years, but the spread of the trees at maturity should always be provided for. The future cutting out of each alternate tree is a pleasing illusion, but in reality a sad delusion, because it is so rarely done, and never done soon enough.

Some protective guard against ill-bred horses, worse-bred boys, careless workmen on the street or adjacent lots, and the daily run of miscellaneous accidents, is necessary for years. Nothing yet invented is conveniently applicable to small trees or always effective. A temporary railing on the curb line, though unsightly, is more useful than a casing for each tree. When the trunk becomes thick enough, a strip of fine galvanized wire netting wrapped loosely around it as far up as a horse can reach is cheap, serviceable, neat, unobtrusive, and can readily be adjusted to the growth of the tree from year to year. The damage done to street trees by horses and careless usage of workmen about them is incalculable. Prosecution is useless, because an adequate penalty that would deter others is never imposed.

The gist of the whole matter may be summed up in the form of sententious advice. Select the kinds of trees that experience commends to you as most likely to satisfy your own taste. Select young trees only, of thrifty habit and good form. Furnish good soil in ample quantity at whatever cost or trouble. Handle and transplant with proper care and skill. Mulch and water effectively until the trees be fully established. Guard from damage by any device that will serve your purpose. Fight to the death every pest and plague as soon as it appears. Give constant watchfulness to the trees’ welfare while you live, and, in making your will, impose the same duty upon the successors to your trust when you die. “Eternal vigilance is the price” of every street tree.