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reproduces both by seed and by sprouts (see Fig. 12). It produces seed fairly abundantly every year, but about once in three years there is an extremely heavy production. The tree begins to bear seed when twenty-five to thirty years old, and seeds vigorously up to an age of one hundred and fifty years, when its productive power begins to diminish. A great part of the seed, however, is abortive. Red gum is not fastidious in regard to its germinating bed; it comes up readily on sod in old fields and meadows, on decomposing humus in the forest, or on bare clay-loam or loamy sand soil. It requires a considerable degree of light, however, and prefers a moist seed bed. The natural distribution of the seed takes place for several hundred feet from the seed trees, the dissemination depending almost entirely on the wind. A great part of the seed falls on the hardwood bottom when the land is flooded, and is either washed away or, if already in the ground and germinating, is destroyed by the long-continued overflow. After germinating, the red gum seedling demands, above everything else, abundant light for its survival and development. It is for this reason that there is very little growth of red gum, either in the unculled forest or on culled land, where, as is usually the case, a dense undergrowth of cane, briers, and rattan is present. Under the dense underbrush of cane and briers throughout much of the virgin forest, reproduction of any of the merchantable species is of course impossible. And even where the land has been logged over, the forest is seldom open enough to allow reproduction of cottonwood and red gum. Where, however, seed trees are contiguous to pastures or cleared land, scattered seedlings are found springing up in the open, and where openings occur in the forest, there are often large numbers of red gum seedlings, the reproduction generally occurring in groups. But over the greater part of the Southern hardwood bottom land forest reproduction is very poor. The growth of red gum during the early part of its life, and up to the time it reaches a diameter of eight inches breast-high, is extremely rapid, and, like most of the intolerant species, it attains its height growth at an early period. Gum sprouts readily from the stump, and the sprouts surpass the seedlings in rate of height growth for the first few years, but they seldom form large timber trees. Those over fifty years of age seldom sprout. For this reason sprout reproduction is of little importance in the forest. The principal requirements of red gum, then, are a moist, fairly rich soil and good exposure to light. Without these it will not reach its best development.

A Cypress Slough in the Dry Season

Fig. 13. A Cypress Slough in the Dry Season.

Second-Growth Red Gum

Second-growth red gum occurs to any considerable extent only on land which has been thoroughly cleared. Throughout the South there is a great deal of land which was in cultivation before the Civil War, but which during the subsequent period of industrial depression was abandoned and allowed to revert to forest. These old fields now mostly covered with second-growth forest, of which red gum forms an important part (see Fig. 12). Frequently over fifty per cent of the stand consists of this species, but more often, and especially on the Atlantic coast, the greater part is of cottonwood or ash. These stands are very dense, and the growth is extremely rapid. Small stands of young growth are also often found along the edges of cultivated fields. In the Mississippi Valley the abandoned fields on which young stands have sprung up are for the most part being rapidly cleared again. The second growth here is considered of little value in comparison with the value of the land for agricultural purposes. In many cases, however, the farm value of the land is not at present sufficient to make it profitable to clear it, unless the timber cut will at least pay for the operation. There is considerable land upon which the second growth will become valuable timber within a few years. Such land should not be cleared until it is possible to utilize the timber.

39. Tupelo Gum (Nyssa aquatica) (Bay Poplar, Swamp Poplar, Cotton Gum, Hazel Pine, Circassian Walnut, Pepperidge, Nyssa). The close similarity which exists between red and tupelo gum, together with the fact that tupelo is often cut along with red gum, and marketed with the sapwood of the latter, makes it not out of place to give consideration to this timber. The wood has a fine, uniform texture, is moderately hard and strong, is stiff, not elastic, very tough and hard to split, but easy to work with tools. Tupelo takes glue, paint, or varnish well, and absorbs very little of the material. In this respect it is equal to yellow poplar and superior to cottonwood. The wood is not durable in contact with ground, and requires much care in seasoning. The distinction between the heartwood and sapwood of this species is marked. The former varies in color from a dull gray to a dull brown; the latter is whitish or light yellow like that of poplar. The wood is of medium weight, about thirty-two pounds per cubic foot when dry, or nearly that of red gum and loblolly pine. After seasoning it is difficult to distinguish the better grades of sapwood from poplar. Owing to the prejudice against tupelo gum, it was until recently marketed under such names as bay poplar, swamp poplar, nyssa, cotton gum, circassian walnut, and hazel pine. Since it has become evident that the properties of the wood fit it for many uses, the demand for tupelo has largely increased, and it is now taking rank with other standard woods under its rightful name. Heretofore the quality and usefulness of this wood were greatly underestimated, and the difficulty of handling it was magnified. Poor success in seasoning and kiln-drying was laid to defects of the wood itself, when, as a matter of fact, the failures were largely due to the absence of proper methods in handling. The passing of this prejudice against tupelo is due to a better understanding of the characteristics and uses of the wood. Handled in the way in which its particular character demands, tupelo is a wood of much value.

Uses of Tupelo Gum

Tupelo gum is now used in slack cooperage, principally for heading. It is used extensively for house flooring and inside finishing, such as mouldings, door jambs, and casings. A great deal is now shipped to European countries, where it is highly valued for different classes of manufacture. Much of the wood is used in the manufacture of boxes, since it works well upon rotary veneer machines. There is also an increasing demand for tupelo for laths, wooden pumps, violin and organ sounding boards, coffins, mantelwork, conduits and novelties. It is also used in the furniture trade for backing, drawers, and panels.

Range of Tupelo Gum

Tupelo occurs throughout the coastal region of the Atlantic States, from southern Virginia to northern Florida, through the Gulf States to the valley of the Nueces River in Texas, through Arkansas and southern Missouri to western Kentucky and Tennessee, and to the valley of the lower Wabash River. Tupelo is being extensively milled at present only in the region adjacent to Mobile Ala., and in southern and central Louisiana, where it occurs in large merchantable quantities, attaining its best development in the former locality. The country in this locality is very swampy (see Fig. 11), and within a radius of one hundred miles tupelo gum is one of the principal timber trees. It grows only in the swamps and wetter situations (see Fig. 11), often in mixture with cypress, and in the rainy season it stands in from two to twenty feet of water.

40. Black Gum (Nyssa sylvatica) (Sour Gum). Black gum is not cut to much extent, owing to its less abundant supply and poorer quality, but is used for repair work on wagons, for boxes, crates, wagon hubs, rollers, bowls, woodenware, and for cattle yokes and other purposes which require a strong, non-splitting wood. Heartwood is light brown in color, often nearly white; sapwood hardly distinguishable, fine grain, fibres interwoven. Wood is heavy, not hard, difficult to work, strong, very tough, checks and warps considerably in drying, not durable. It is distributed from Maine to southern Ontario, through central Michigan to southeastern Missouri, southward to the valley of the Brazos River in Texas, and eastward to the Kissimmee River and Tampa Bay in Florida. It is found in the swamps and hardwood bottoms, but is more abundant and of better size on the slightly higher ridges and hummocks in these swamps, and on the mountain slopes in the southern Alleghany region. Though its range is greater than that of either red or tupelo gum, it nowhere forms an important part of the forest.

HACKBERRY

41. Hackberry (Celtis occidentalis) (Sugar Berry, Nettle Tree). The wood is handsome, heavy, hard, strong, quite tough, of moderately fine texture, and greenish or yellowish color, shrinks moderately, works well and stands well, and takes a good polish. Used to some extent in cooperage, and in the manufacture of cheap furniture. Medium- to large-sized tree, locally quite common, largest in the lower Mississippi Valley. Occurs in nearly all parts of the eastern United States.

HICKORY

The hickories of commerce are exclusively North American and some of them are large and beautiful trees of 60 to 70 feet or more in height. They are closely allied to the walnut, and the wood is very like walnut in grain and color, though of a somewhat darker brown. It is one of the finest of American hardwoods in point of strength; in toughness it is superior to ash, rather coarse in texture, smooth and of straight grain, very heavy and strong as well as elastic and tenacious, but decays rapidly, especially the sapwood when exposed to damp and moisture, and is very liable to attack from worms and boring insects. The cross-section of hickory is peculiar, the annual rings appear like fine lines instead of like the usual pores, and the medullary rays, which are also very fine but distinct, in crossing these form a peculiar web-like pattern which is one of the characteristic differences between hickory and ash. Hickory is rarely subjected to artificial treatment, but there is this curious fact in connection with the wood, that, contrary to most other woods, creosote is only with difficulty injected into the sap, although there is no difficulty in getting it into the heartwood. It dries slowly, shrinks and checks considerably in seasoning; is not durable in contact with the soil or if exposed. Hickory excels as wagon and carriage stock, for hoops in cooperage, and is extensively used in the manufacture of implements and machinery, for tool handles, timber pins, harness work, dowel pins, golf clubs, and fishing rods. The hickories are tall trees with slender stems, never forming forests, occasionally small groves, but usually occur scattered among other broad-leaved trees in suitable localities. The following species all contribute more or less to the hickory of the markets:

42. Shagbark Hickory (Hicoria ovata) (Shellbark Hickory, Scalybark Hickory). A medium- to large-sized tree, quite common; the favorite among the hickories. Heartwood light brown, sapwood ivory or cream-colored. Wood close-grained, compact structure, annual rings clearly marked. Very hard, heavy, strong, tough, and flexible, but not durable in contact with the soil or when exposed. Used for agricultural implements, wheel runners, tool handles, vehicle parts, baskets, dowel pins, harness work, golf clubs, fishing rods, etc. Best developed in the Ohio and Mississippi basins; from Lake Ontario

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