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spikes, as the annual layers readily separate, by repeated blows, or by frequent bending. In Nova Scotia, New Brunswick, and the northern states of the union, it is preferred to the white ash for hoops; and, as the concentric layers readily yield by malling, they are separated into long strips, often as thin as a wafer, which are much used in the country in the manufacture of baskets, corn-riddles, and sometimes for the bottoms of chairs. The wood of this variety is more liable than any other to be disfigured with knobs or wens, which are sometimes of considerable size, and are detached from the body of the tree, and made into trays or bowls. The wood of these excrescences has the advantage of superior solidity, and when carefully polished, exhibits very singular undulations of fibre, and might be profitably employed by cabinet-makers and other manufacturers of fancy work. This sort, like most other kinds of ash, is particularly prolific in potash.

5. F. A. SAMBUCIFOLIA CRISPA. Crisp-leaved Elder-leaved American Ash, having curled leaves.

6. F. A. QUADRANGULATA. Quadrangular-branched American Ash; Fraxinus quadrangulata, of Michaux, Don, Loudon, and others; Frêne quadrangulaire, Frêne bleu, of the French; Blue Ash, of the Anglo-Americans. This variety, in favourable situations, often attains a height of sixty or seventy feet, with a diameter of fifteen or twenty inches. The bark of the trunk cracks and separates into thin plates much in the same manner as that of the white oak (Quercus alba.) The leaves are from twelve to eighteen inches long, and are composed of from two to four pairs of leaflets, terminated by an odd one. The leaflets are almost sessile, elliptic-lanceolate, distinctly toothed, smooth on the upper surface, and downy beneath. The branches are quadrangular; and the young shoots to which the leaves are attached, are distinguished by four opposite membranes, nearly one third of an inch broad, that are of a greenish colour, and extend through their entire length. This character disappears in the third or fourth year, leaving only the traces of its existence. The flowers, which put forth in May, are succeeded by samaræ that are flat from one extremity to the other, and blunt at both ends, but a little narrowed towards the base. The blue ash is chiefly found in Tennessee, Kentucky, and the southern part of Ohio, where the climate is mild, and the soil fertile in an extreme degree. This fertility seems to serve as a substitute for that degree of moisture, which, in the Atlantic states, appears to be indispensable to the growth of the ash. The wood of this tree possesses the characteristic properties of the genus; and, of all the varieties of the western states, it is the most extensively employed, and the most highly esteemed. Besides the habitual use that is made of it for the frames of carriages, and for the felloes of wheels, agricultural implements, &c., it is generally selected for the flooring of houses, and frequently for their exterior covering; and, where the tulip-tree, (Liriodendron,) does not abound, it sometimes serves for the shingles of their roofs. It is said that a blue colour may be extracted from the bark of this tree; from which circumstance, probably, it derives its common name. It was introduced into Britain in 1823, and is to be met with in many of the European and American collections.

7. F. A. QUADRANGULATA NERVOSA. Conspicuous-nerved-leaved. Quadrangularbranched American Ash.

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8. F. A. JUGLANDIFOLIA. Walnut-leaved American Ash; Fraxinus viridis, of Michaux, Fraxinus juglandifolia, of Don, Loudon, and others; Frêne à feuilles de noyer, Frêne vert, of the French; Green Ash, of the Anglo-Americans. This tree, in its natural habitat, usually attains a height of twenty-five or thirty feet, with a trunk four or five inches in diameter; but in a state of cultivation, it has exceeded more than double of these dimensions. It is easily recognized by the brilliant green colour of its young leaves; and by its leaves being nearly of the same colour on both surfaces. From this uniformity, which is rarely observed in the foliage of trees, Dr. Mühlenberg applied the specific name, concolor; and Michaux gave this tree the popular name of the “Green Ash.” The branches are glabrous, and, like the buds, are of a grayishbrown. The leaves vary in length from six to fifteen inches, with from two to four pairs of leaflets, and an odd one, according to the vigour of the tree, and to the coolness of the soil in which it grows. The leaflets, which are about three inches long, are membranous, glabrous, but not shining, sometimes canescent or glaucous beneath, downy in the axils of the veins, stalked, elliptic-lanceolate, distinctly denticulated, with glabrous petioles. The flowers, which put forth in May, occur in pendulous corymbs, and are succeeded by linear samaræ, similar in form to those of the white ash, but only about one half as large. This variety is a native of wet, shady woods, from Canada to Carolina; but is more common in the western parts of Pennsylvania, Maryland, and Virginia, than in any other sections of the United States. It is also found in abundance on the banks of the Monongahela and of the Ohio. Its wood is distinguished by similar properties as that of the other trees of the genus, and is applied, in the regions where it abounds, to similar purposes; but as the white ash and the brownhearted variety are more common where it grows, which are much superior in size, the green ash is only incidentally employed. It was introduced into Britain in 1724, where it is only considered as an ornamental tree. The finest specimen, probably existing in the known world, is on Pope's Villa, at Twickenham, in England, which has attained a height of nearly seventy feet, with a trunk three feet in diameter, and an ambitus or spread of branches as great as its height. This splendid tree, which retains its foliage until Christmas, flowers, but never matures its seeds. This variety was introduced into France in 1775, and is cultivated for ornament in many of the European gardens and collections.

9. F. A. JUGLANDIFOLIA SUBSERRATA. Willdenow. Slightly-toothed Walnutleaved American Ash.

10. F. A. CAROLINIANA. Carolina Ash; Fraxinus platycarpa, of Michaux; Fraxinus caroliniana, of Don, Loudon, and others; Frêne de la Caroline, of the French. This is a very remarkable variety, readily distinguished by the large size of its leaflets, which are nearly round, but acuminated, petiolate, serrated, glabrous and shining above, and seldom consists of more than two pairs of leaflets, with an odd one. In spring, the lower surface of the leaves, and the young shoots, are covered with down, which disappears as the suminer advances. The stature of this tree seldom exceeds thirty feet; and it often flowers and fruits at half of this height. The branches are glabrous, and, like the buds, are of a brownish hue. The flowers, which put forth in May, as in the other varieties, are small, and not very conspicuous. They are succeeded by samaræ which are

unlike those of any of the preceding sorts; being flat, oval, and often almost as broad as they are long. This tree is a native from Pennsylvania to Georgia,

and Cooper Rivers, in South Carolina. From its inferior dimensions, this variety is not much used in the arts; although it possesses properties of eminent utility. It was introduced into Britain in 1783, and is cultivated in many parts of Europe, solely as an ornamental tree.

11. F. A. EPIPTERA. Wing-topped-seeded American Ash; Fraxinus epiptera, of Don, Loudon, and others. This variety may be distinguished by its lanceolate-elliptic leaflets, which are subserrated, opaque, and downy beneath, on the veins. The samaræ are cuneated, obtuse, and emarginate at the apex, and terete at the base. The young branches are green, and covered with white dots; the bark chinky; the buds brown; and the flowers calyculate, which put forth in May. A tree thirty feet high, native of North America, from Canada to Carolina, and was introduced into Britain in 1823.

12. F. A. PLATYCARPA. Broad-fruited American Ash; Fraxinus platycarpa, of Don, Loudon, and others. The leaflets of this variety are almost sessile, very distinctly serrated, elliptic-lanceolate, two inches long, and one inch broad; haying the larger veins villous beneath. The samaræ are elliptic-lanceolate, two inches long, and acute at both ends. A tree from thirty to fifty feet high; native of Virginia and Carolina; introduced into Britain in 1724; and flowers in May. It is very easily known from all other American varieties, by the leaves dying off, in autumn, of a fine purple.

13. F. A. EXPANSA. Expanded American Ash; Fraxinus expansa, of Don, Loudon, and others. The leaflets of this variety occur in five pairs, three inches long, ovate-oblong, unequally serrated, acuminated, glabrous, but not shining, and petiolate. The branches are glabrous, smooth, and green, when young, with the buds brown. A tree from thirty to fifty feet in height; native of North America; introduced into Britain in 1824, and flowers in May.

14. F. A. PULVERULENTA. Powdery-petioled American Ash; Fraxinus pulverulenta, of Don, Loudon, and others.

15. F. A. RUBICUNDA. Reddish-veined American Ash; Fraxinus rubicunda, of Don, Loudon, and others.

16. F. A. LONGIFOLIA. Long-leaved American Ash; Fraxinus longifolia, of Don, Loudon, and others.

17. F. A. VIRIDIS. Green-branched American Ash; Fraxinus viridis, of Don, Loudon, and others (but not F. viridis of Michaux.)

18. F. A. CINERA. Gray-budded American Ash; Fraxinus cinera, of Don, Lou. don, and others.

19. F. A. NIGRA. Black-branched American Ash; Fraxinus nigra, of Don. Loudon, and others.

20. F. A. FUSCA. Brown-branched American Ash; Fraxinus fusca, of Don, Loudon, and others.

21. F. A. RUFA. Rufous-haired-leafleted American Ash; Fraxinus rufa, of Don, Loudon, and others.

22. F. A. PANNOSA. Cloth-like-leaved American Ash; Fraxinus pannosa, of Don, Loudon, and others. A tree with fulvous buds, native of Carolina, introduced into Britain in 1820.

23. F. A. TRIPTERA. Three-winged-fruited American Ash; Fraxinus triptera, of Nuttal, a native of the oak forests of South Carolina.

Geography and History. The Fraxinus americana is a native of North America from Labrador to Carolina; is particularly abundant in Canada and New Brunswick; and, as a cold climate is more congenial to its growth than a warm one, it is found in greater numbers north of the river Hudson than south of it. In the upper part of New Hampshire, it is always accompanied by the white elm, (Ulmus americana,) yellow birch, (Betula excelsa,) white maple, (Acer eriocarpum,) hemlock spruce, (Abies canadensis,) and the black spruce (Abies nigra); and in New Jersey, it is mingled with the red maple, (Acer rubrum,) shell-bark hickory, (Carya alba,) and the sycamore-tree (Platanus occidentalis.)

This species was first introduced into Britain by Mark Catesby, in 1723; and, in about the year 1826, when Cobbett became a nurseryman, and strongly recommended various kinds of American trees, several plantations of the white ash were formed, in different parts of England; but a sufficient time has not yet elapsed to judge of the value of the tree, as compared with the common European ash. In the neighbourhood of London, young trees are generally more or less injured by the spring frosts; nevertheless, in Surrey, at St. Ann's Hill, there is a specimen, which, in thirty-six years after planting, had attained the height of thirty-three feet.

In France, at Clairvault, there is a tree of this species, which had attained the height of thirty feet, in thirty years after planting.

In Russia, the American ash, and several of its varieties, are planted in the government garden, at Odessa, and it is stated by M. le Chevalier Descemet, conseiller de cour, that they have the great advantage of prospering in soils where the European ash will languish." They are not,” says he, "like Fraxinus excelsior, subject to lose their leaves by the ravages of the insect Cantharis vesicatoria, in the middle of summer, and may, consequently, be planted in the neighbourhood of dwelling-houses. They resist the burning heats of summer much better than the European ash-tree, and maintain a deep-green foliage during the hottest weather, when that of the common ash becomes pale, and very frequently withers and drops.” “In short, the American ash-trees," he adds, "deserve to be extensively cultivated in forests, in lines for bordering roads, and in small groups in parks and pleasure-grounds."

It is stated by Mr. John Pearson, in a communication to Dr. James Mease, in the “Memoirs of the Philadelphia Society for promoting Agriculture," for the year 1807, that, in Wayne county, Pennsylvania, there were white ash-trees five feet in diameter, and from fifty to eighty feet in length.

Soil, Situation, Propagation, foc. The most favourite situations of the Fraxinus americana are the banks of rivers and streams, the edges or acclivities of swamps, where the soil is deep and fertile, and intermingled with the fragments of rocks. The propagation and culture of this tree is the same as that of the European species.

Insects, Accidents, foc. The Fraxinus americana, like its European congener, is but little subject to accidents and to the attacks of insects. The only insects that prove particularly injurious to this tree, are the larvæ or borers of the Trochilium denudatum, described by Dr. Harris, in “Silliman's Journal of Science," and also in his “Report on the Insects of Massachusetts injurious to Vegetation." These borers perforate the bark and the sap-wood of the trunk of the ash, from the roots upwards, and are also found in all the branches of any considerable size. The trees thus infested soon show symptoms of disease, in the death of the branches near the summit; and when these insects become numerous, the trees no longer increase in size and height, and premature decay and death ensue. These insects assume the chrysalis form in June and July, when they may be seen projecuing half way out of their round holes in the bark of the trees, during which months, their final transformation is effected, when they burst forth, and escape in the winged state.

Properties and Uses. The wood of the white ash, in young, thrifty trees, is very white from the bark to the centre; but in large, old trees, the heart-wood is

of a reddish tinge, and the sap-wood white. When the annual layers are thick and coarse, it is excecdingly tough and elastic, and may be applied to all the various purposes for which the Fraxinus excelsior is used in Europe. In America, the wood of this tree is highly esteemed for its strength and suppleness, and is advantageously employed for a great variety of uses, of which we shall mention only a few of the most common. It is selected by coach and wagon-makers for the felloes of wheels, for shafts, and for the frames of carriage bodies, and for those of light wagons. It is also in very general use for agricultural implements and domestic wares, particularly for the handles of spades, hoes, shovels, forks, rakes, scythes, &c. In Canada, and the northern parts of the United States, it is extensively used for hoops and staves, the latter of which are of a quality between those of the white and red oaks, and are esteemed best for casks containing salted provisions and flour. It has also been admitted into the lower frames of vessels, but is considered inferior to that of the yellow birch, (Betula excelsa,) and to the heart of the red beech. For the blocks to pulleys, particularly those used in ships, and the pins for belaying the cordage, this wood is very appropriate; and, on account of its strength and elasticity, it is esteemed as superior to every other species of timber-for oars. It is extensively exported to Europe, especially to England, in the form of planks, and the oars of this wood are used in all the navies of the world. The inner bark of this tree imparts a very permanent yellow to skins, and may be used with advantage in dyeing wool.

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