Highways and Highway Transportation

by George R. Chatburn

Locust.—The name locust seems to have been applied to three distinct genera of the family Leguminosae. The black locust (Robinia pseudacia) is a fine appearing tree but in the Middle West is much subject to attack by borers. In other regions it does not seem to suffer that way. It attains a height of 50 to 75 feet, and a spread half as great. The honey locust, a little larger tree, 75 to 90 feet high, with a spread of 30 to 40 feet, is less subject to borer attack, and is one of the hardiest trees for Western Kansas[215] upland planting. The long compound thorns are sometimes objectionable, but these may be avoided by selecting only those specimens having no thorns, for the thorns are frequently absent. As a road tree the honey locust is worthy of much attention. Another genus of locusts is the ordinary mesquite (Prosopis juliflora) of the so-called desert regions. They sometimes grow to 40 or 50 feet in height, sometimes they are a shrub. They are naturally a dry country plant and should be used in places where the moisture is scanty. It is said,[216] “The easily agitated foliage cools the air to a surprising degree.” The “cool shade of the mesquite” is a characteristic phrase. A valuable tree in its own region. The roots furnish wood, the pods are filled with a sweetish pulp from which the Indians, it is said, made “bread, cake, and fermented drink.” “A black dye is obtained from the sap, and a good mucilage from the gum.”

Magnolia.—See [Laurel].

Maple.—One of the best road trees, by some considered superior to Elm. The hard maple (Acer saccharum), the soft maple (Acer saccharinum), are the principal American species of the genus, comprising very many, which grow in the Northern Hemisphere. The Norway maple (Acer platanoides) similar to the hard or sugar maple, has been imported and is used to a considerable extent. The hard maple in New York state and the east is a rapid growing tree; when transplanted to the plains region its growth is very slow. The Norway maple seems to be more rapid, but that too, is slow in those regions. Hard maples grow to 70 or 100 or more feet in height with a spread of nearly the same. When allowed to grow individually and branch from the ground, they form an oval top nearly as wide as high. The shade is dense and the numerous branches in winter and heavy foliage in summer give to the tree a very fine appearance. The leaves turn yellow and scarlet in the fall giving to the woods a most fascinatingly gorgeous aspect. What has been said about the hard maple is true in a lesser extent of soft maples. In the western part of the Mississippi Valley the soft maple is a much more rapid grower. The height attained is not quite so great, 40 to 90 feet. They have when allowed room a fine shape sometimes suggesting elm. The leaves are silvery white beneath, which is why they are sometimes called silver maple. They do not turn so yellow or so red in autumn as the hard maple. On the whole a road tree that may be recommended. The red maple has been mentioned under the name box elder. The Oregon maple (Acer macrophyllum) about the same size as the soft maple is one of the most ornamental broad-leaved trees on the Pacific Coast.

Mulberry.—Red and white, named from the color of the ripe fruit, under good conditions attain a height of 40 to 60 feet, and are quite ornamental. The fruit is sweet, lacking in acid, but is liked by the birds and by some people. A Russian shrub variety is used for low hedges and stands trimming remarkably well.

Oak.—The oaks not only furnish the finest of building lumber but are practically all good ornamental trees. The principal reasons they are not used more are the difficulty of transplanting them and their slow growth. However, they are well worth the trouble and wait. The oaks, of which there are some 300 species, are found native in most of the Northern Hemisphere and in a few places south of the equator. They are usually classified as white oaks, red oaks and live oaks. They are quite easily distinguished by the foliage, bark, and general appearance of the trees, but not easily, always, by the wood. In all cases the fruit is an acorn, an oval or oblongly lanceolate smooth nut having a thin shell and partly enclosed in a scaly woody cup. A dozen or more species could be described as good road and park trees, but a few will suffice. White oak (Quercus alba) is widespread throughout the north central and eastern United States. It rises to 75 or 100 feet in height and spreads nearly as much. It is truly a magnificent tree when grown. The cow oak (Q. michauxii) grows best in a slightly more southern region, is nearly the same size. The chestnut oak (Q. prinus) is slightly smaller, is found along the eastern border, has leaves somewhat resembling a chestnut, and reaches 75 to 80 feet in height. Post oak (Q. minor), still smaller, inhabits the Gulf states. Bur oak (Q. macrocarpa), one of the largest of the oaks, extends farthest west and northwest of the eastern oaks. It is recommended for prairie planting. The red oak, (Q. rubea) best in the Northeastern states, is found native as far west as Nebraska. It is 90 to 100 feet in height, is rather more upright than the white oaks, the spread not so great. The pin oak (Q. palustris) has proven itself well adapted for transplanting. Since it has a straight upright trunk and symmetrical body is a good street and road tree, at least as far west as Nebraska. The live oaks (Q. virginiana), (Q. agrifolia), (Q. chrysotepis) do well in the Southern states and in California. They grow from 50 to 80 feet in height and are evergreen. Q. bicolor, and the scarlet oak, Q. coccinea, are also recommended for landscape gardening.

Orange.—See [Citrus Fruit].

Osage Orange.—Used extensively for hedges, hence the name sometimes given to it, “hedge.” Fruit resembles an orange. Long thorns. Wood hard, but checks badly in drying; heart, a beautiful orange, sapwood yellow. Makes very durable fence posts.

Palm.—Palms come under the division Endogenous, or those that increase from within. Yuccas, cornstalks, sugar cane, bamboos are other examples of endogens. There are 1000 or more species of palms. Some of them are very decorative and in regions where they grow, such as Southern California and Florida, may be used very effectively for road and park embellishment. The Washington palm (Washingtonia filifera) grows to a height of 30 to 60 feet, with a tuft of fan-shaped leaves at the top. Old leaves die and hang down the tree like a thatched roof. Sometimes these are trimmed off, leaving a smooth stem nearly the same size all the way up. They are very effective in producing rows or avenues. Cabbage palmetto (Sabal palmetto) also has a long stem with a tuft of leaves at the top. The date palm (Phoenix dactylifera) has been grown quite successfully in Arizona. Several other species are available.

Pecan.—See [Hickory].

Pepper.—Snow[217] states that the California pepper tree or Peruvian mastic (Schinus molle) was introduced into California from Peru by the early Spanish missions. It is now a very popular street and road tree. In general appearance it suggests the drooping foliage of the weeping willow. It is very irregular and grows to 30 or 50 feet high with a spread nearly as great. The fine fern-like foliage and the long sprays of rose tinted berries make it very ornamental. It gives off a pleasant pungent peppery odor, and it is claimed to have the property of stopping dust, something greatly needed during the summer season in California.