Trees Worth Knowing Part 24

=The Screw-bean=

_P. p.u.b.escens_, Benth.

The screw-bean or screw-pod mesquite is a small slender-trunked tree with sharp spines at the bases of the h.o.a.ry foliage. The marked distinction between this species and the preceding one is in the fruit, which makes from twelve to twenty turns as it matures, and forms when ripe a narrow straight spiral, one to two inches long; but when drawn out like a coiled spring the pod is shown to be more than a foot in length. These sweet nutritious pods are a most useful fodder for range cattle, and the wood is used for fencing and fuel.

This tree grows from southern Utah and Nevada through New Mexico and Arizona into San Diego County, California, western Texas and northern Mexico.

=The Palo Verde Acacia=

_Cercidium Torreyanum_, Sarg.

The palo verde is another green-barked acacia whose leaves are almost obsolete. Miniature honey-locust leaves an inch long unfold, a few here and there in March and April, but they are gone before they fully mature, and the leaf function is carried on entirely by the vivid green branches. Cl.u.s.tered flowers, like little yellow roses, cover the branches in April, and the pointed pods ripen and fall in July.

In the Colorado desert of southern California, in the valley of the lower Gila River in Arizona, on the sides of low canyons and on desert sandhills into Mexico, this small tree, with its mult.i.tude of leafless, ascending branches, is one of the brightest features on a hopelessly dun-colored landscape.

=The Jamaica Dogwood=

_Icthyomethia Piscipula_, A. S. Hitch.

The Jamaica dogwood is a West Indian tree that grows also in southern Florida and Mexico. It is one of the commonest tropical trees on the Florida West Coast from the sh.o.r.es of Bay Biscayne to the Southern Keys. The leaves are four to nine inches long, with leaflets three to four inches in length, deciduous, vivid green, making a tree fifty feet high an object of tropical luxuriance. Its beauty is greatly enhanced in May by the opening of the pink, pea-like blossoms that hang in drooping cl.u.s.ters a foot or more in length. The necklace-like pods are frilled on four sides with thin papery wings.

The wood of this tree is very durable in contact with water, besides being heavy, close-grained, and hard. It is locally used in boat-building, and for fuel and charcoal. All parts of the tree, but especially the bark of the roots, contain an acid drug of sleep-inducing properties. In the West Indies the powdered leaves, young branches, and the bark of the roots have long been used by the natives to stupefy fish they try to capture.

=The Horse Bean=

_Parkinsonia aculeata_, Linn.

The horse bean or retama, native to the valleys of the lower Rio Grande and Colorado River, is a small graceful pod-bearing tree of drooping branches set with strong spines, long leaf-stems, branching and set with many pairs of tiny leaflets.

The bright yellow, fragrant flowers are almost perennial. In Texas the tree is out of bloom only in midwinter. In the tropics, it is ever-blooming. The fruit hangs in graceful racemes, dark orange-brown in color, and compressed between the remote beans. As a hedge and ornamental garden plant, this tree has no equal in the Southwest. It is met with in cultivation in most warm countries.

=The Texas Ebony=

_Zigia flexicaulis_, Sudw.

The Texas ebony is a beautiful, acacia-like tree of southern Texas and Mexico. One of the commonest and most beautiful trees on the bluffs along the coast, south of the Rio Grande. Its leaves are feathery, fern-like, its flowers in creamy cl.u.s.ters, its pods thick, almost as large as those of the honey locust. The seeds are palatable and nutritious, green or ripe. Immature, the pods are cooked like string beans; ripe, they are roasted, and the pods themselves are ground and used as a subst.i.tute for coffee.

The wood is valuable in fine cabinet work, and because it is almost indestructible in contact with the ground, it is largely used for fence posts. It makes superior fuel. Besides being more valuable than any other tree of the Rio Grande Valley, though it rarely exceeds thirty feet in height, it is worthy of the attention of gardeners as well as foresters in all warm temperate countries.

Prof. Sargent calls it the finest ornamental tree native to Texas.

=The Frijolito=

_Sophora secundiflora_, DC.

The frijolito or coral-bean is a small, slender narrow-headed tree, with persistent, locust-like leaves, fragrant violet-blue flowers, and small one-sided racemes. The pods are silky white, pencil-like, constricted between the bright scarlet seeds. The tree grows wild in canyons in southern Texas and New Mexico, forming thickets or small groves in low moist limestone soil and stream borders. It is a close relative of the famous paG.o.da tree of j.a.pan, _S. j.a.ponica_, universally cultivated; and it deserves to be a garden tree throughout the Southern states.

PART VII

DECIDUOUS TREES WITH WINGED SEEDS

The Maples--The Ashes--The Elms

THE MAPLES

A single genus, _acer_, includes from sixty to seventy species, widely distributed over the Northern Hemisphere. A single species goes south of the equator, to the mountains of Java. All produce pale close-grained, fairly hard wood, valued in turnery and for the interior finish of houses. The clear sap of some American species is made into maple sugar.

The signs by which we may know a member of the maple family are two: opposite, simple leaves, palmately veined and lobed; and fruits in the form of paired samaras, compressed and drawn out into large thin wings. No amount of improvement changes these family traits. No other tree has both leaves and fruits like a maple's.

The distribution of genus _acer_ is interesting. The original home of the family is in the Far East. In China and j.a.pan we may reckon up about thirty indigo maples, while only nine are native to North America. Of these, five are in the eastern half of the continent, three in the West, and one grows indifferently on both sides of the Great Divide.

=The Sugar Maple=

_Acer saccharum_, Marsh.

The sugar maple (_see ill.u.s.tration, page 198-199_) is economically the most important member of its family in this country. As an avenue and shade tree it is unsurpa.s.sed. It is the great timber maple, whose curly and bird's-eye wood is loved by the cabinet-maker; and whose sap boiled down, yields maple sugar--a delicious sweet, with the distinctive flavor beloved by all good Americans. In October the sugar maple paints the landscape with yellow and orange and red. Its firm broad leaves, shallowly cleft into five lobes, are variously toothed besides. The flowers open late, hanging on the season's shoots in hairy yellow cl.u.s.ters. The key fruits are smooth and plump, with wings only slightly diverging. They are shed in midsummer.

Hard maple wood outranks all other maple lumber, though the curly grain and the bird's-eye are accidental forms rarely found. Flooring makes special demands upon this wood. Much is used in furniture factories; and small wares--shoe lasts, shoe pegs and the like--consume a great deal.

As fuel, hard maple is outranked only by hickory. Its ashes are rich in potash and are in great demand as fertilizer in orchards and gardens.

The living tree, in the park, on the street, casting its shade about the home, or glowing red among the trees of the woods, is more valuable than its lumber. Slow-growing, strong to resist damage by storm, clean in habit and beautiful the year round--this is our splendid rock maple.

Rich, indeed, is the city whose early inhabitants chose it as the permanent street tree.

=The Black Maple=

_A. nigrum_, Michx.

The black maple is so like the sugar maple that they are easily confused, but its stout branchlets are orange-colored, the leaves are smooth and green on both sides, scantly toothed, and they droop as if their stems were too weak to hold up the blades. The keys spread more widely than those of the sugar maple.

The black maple is the sugar maple of South Dakota and Iowa. It becomes rarer as one goes east. It is an admirable lumber tree, as well as a n.o.ble street and shade tree.

Two soft maples are found in the eastern part of the country, their sap less sweet, their wood softer than the hard maples, and their fitness for street planting correspondingly less.

=The Red Maple=

_A. rubrum_, Linn.

The red maple is a lover of swamps. It thrives, however, on hillsides, if the soil be moist; and is planted widely in parks and along village streets. In beauty it excels all other maples. In early spring its swelling buds glow like garnets on the brown twigs (_see ill.u.s.trations, pages 198-199_). The opening flowers have red petals, and the first leaves, which accompany the early bloom, are red. In May the dainty flat keys, in cl.u.s.ters on their long, flexible stems, are as red as a c.o.c.k's comb, and beautiful against the bright green of the new foliage. In early September in New England, a splash of red in the woods, across a swamp, is sure to be a scarlet maple that suddenly declares its name. Against the green of a hemlock forest these maples show their color like a splash of blood. The tree is gorgeous.