1708

ARBORETUM AND FRUTICETUM.

PART III.

soil is dry and meagre. In such situations, it commonly attains the heightof 20 ft. or 25 ft.; hut single trees, in moist places, grow to nearly doublethat height, with trunks from 8 in. to 9 in. in diameter. It is less com-mon in America than any other species of birch, being rarely found ingroups; and single trees are met with only at considerable intervals. It ismost common in the district of Maine; but, even there, it is only seen by thesides of the highways, and in sandy soils that have been exhausted by cultiva-tion. The wood is very soft, brilliant when polished, and perfectly white;hut it speedily decays, and, in America, is employed for no purpose, not evenfor fuel. The twigs are too brittle for common brooms. It was first culti-vated in England by Archibald Duke of Argyll, at Whitton, in 1750; and itis to be met with in the principal British and Continental nurseries. Whenthe plants are raised from seed, they make very handsome trees; and, as seedis freely produced, this mode ought always to he adopted: but plants fromlayers seldom attain any magnitude. The largest trees that we know of inthe neighbourhood of London are at Purser’s Cross and Syon ; where, how-ever, they are under 50 ft. in height. In the Fulham Nursery, there is one30 ft. high; and the largest tree of this kind in England, seems to be at Dod-dington, in Gloucestershire, where it is 60 ft. high. In Ireland, in the Glas-nevin Botanic Garden, 35 years planted, it is 30 ft. high. The price of plants,in the London nurseries, is from Is. to Is. 6d. each, and seeds Is. per quart;at New York, plants are 10 cents each, and seeds 60 cents per pound, or5 dollars per bushel.

If 8. B. papyra'cea Ait. The Paper Birch.

Identification. Ait. Hort. Kew., 3. p. 337.; Willil. Sp. Pi., 4. p. 464., Baum., p. 58. ; N. Du Ham.,3. p. 205.; Pursh FI. Amer. Sept., 2. p. 621.

Synonymes. B. papyrifera Michx. Fl. Bor. Amer., 2. p. 180., Marshal, p. 36. ; B. lanceol&ta Hort.;B. rubra Lodd. Cut., ed. 1836 ; B. canadensis Bodd. Cat. ; B. nigra of the Paris nurseries ; CanoeBirch, white Birch, Amer.

Engravings. Michx. Arb., 2. t. 1. j Willd. Baum., t. 1. f. 1. ; ourj?g. 15GI.; and the plate of thistree in our last Volume.

Spec . Char.yfyc. Leaves ovate, acuminate, doubly serrate; veins hairv be-neath; petiole glabrous. Female catkins on long footstalks, drooping;scales having the side lobes short, somewhat orbiculate. (Wi/ld. Sp. PL, iv.p. 464.) A North American tree, attaining 60 ft. or 70 ft. in height; andflowering, in America, in May and June. Introduced in 1750.

Varieties.

3^ B. p. 2 fusca, B. fusca Bose. —This variety is mentioned, in the Nouveau Du Hamel, as havingbeen collected by Bose in Carolina. The leaves are smaller than those of the species,and less downy. The branches, covered with a short soft down, of a brownish colour,somewhat resemble those of B. nigra Ait.

i B. p. 3 trichdclada Hort.,has extremely hairy branches, and its twigs in threes. It has heart-shaped leaves. There is a tree in the Horticultural Society’s Garden.

B. p. 4 platyphylla Hort. has very broad leaves.

Description, Sfc. The largest size which this tree attains in North America,according to Michaux, is about 70 ft. in height, with a trunk 3 ft. in diameter;but a writer in the Gardener’s Magazine mentions trees which girt from 18 ft.to 20 ft. in the settlements of the Hudson’s Bay Company. Its branches areslender, flexible, and covered with a shining brown bark, dotted with white. Theleaves are borne on petioles four or five lines long, and are of a middling size,oval, unequally denticulated, smooth, with scarcely any hairs, and of adarkgreen.The catkins are pendulous, and about 1 in. in length: the seeds are ripe towardsthe middle of July. On trees the trunks of which do not exceed 8 in. in di-ameter the bark is of a brilliant white; and is as indestructible as the barkof B. alba. The heart wood of this tree, when first laid open, is of a reddishhue; and the sap wood is perfectly white. It has a fine glossy grain, with aconsiderable share of strength; but speedily decays when exposed to alternatedryness and moisture. Michaux considers it, however, equal in point of usefulproperties to the white birch of Europe. A section of the trunk of a full-grown tree, 1 ft. or 2 ft. in length, immediately below the first ramification,exhibits very elegant undulations of the fibre, representing bunches of feathers,or sheaves of corn. These pieces are divided by cabinet-makers into thin,