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Though the birch may be propagated by layers, and even by cuttings, yet plants are not readily produced otherwise than by seed; and those of certain varieties, which are procured from layers, or by inarching, never appear to grow with the same vigour as seedlings. Birch seed ripens in September and October ; and may be either gathered and sown immediately, or preserved in a dry loft, and sown in spring. Sang directs particular attention to be paid to gathering the seeds only from weeping trees; and this we know to be the directions given to the collectors employed by the nurserymen in the north of Scotland. If the seeds are to be sown immediately, the catkins may be gathered wet; but, if they are to be kept till spring, they ought not to be gathered except when quite dry; and every day's gathering should be carried to a dry loft and spread out thinly, as they are very apt to heat when kept in sacks, or laid up in heaps. The seeds should be sown in very fine, light, rich soil, in beds of the usual width, and very slightly covered. Boutcher says: “ Sow the seeds and clap them into the ground with the back of the spade, without any earth spread over them, and throw a little peas haulm over the beds for three or four weeks, till the seeds begin to vegetate. The peas haulm will keep the ground moist, exclude frost, and prevent the birds from destroying the seeds.” (Treat. on Forest Trees, p. 13.). “It is scarcely possible," Sang observes, “ to cover birch seeds too little, if they be covered at all.” The plants, if sown in autumn, will come up in the March or April following. If sown in spring, they will come up in May or June; which, in very cold climates, is a preferable season. If any danger is apprehended from moisture in the soil during winter, the alleys between the beds may be deepened, so as to act as drains. In the nursery lines, the plants require very little pruning, and their after-care, when in plantations, is equally simple.
Wherever the birch abounds in woods or coppices, a great many seedling plants spring up; and these, in various parts of England, are collected by the country people, and sold to the nurserymen. This is, indeed, the mode by which young trees and hedge plants of every kind were obtained before the establishment of commercial nurseries. Young birch plants which have been pulled out of coppice woods, when about two years old, we are informed by Messrs. Young and Penny, of the Milford Nursery, who adopt the practice extensively, are found to root much better than seedlings of the saine age and size taken out of a regular seed-bed; doubtless because, in the latter case, a greater proportion of the taproot requires to be cut off. In the case of the young birches pulled out of the copses, the taproot, which could not get far down into the hard soil, has its substance in a more concentrated form, and is more branching; hence, little requires to be cut off it, except the ragged rootlets, or fibres; and it may be considered as acting as a bulb to the upper part of the plant. The tops of these seedling birches are shortened before planting; and the plants, Mr. Young informs us, make as much wood in one year as regular nursery-reared birch seedlings will in two. It is found in this part of the country, that the downy-leaved black-barked seedling birches (B. a. pubescens) stole much more freely, when cut down as coppice-wood, than the smooth-leaved white-barked weeping variety (B. a. péndula). (See Gard. Mag., vol. xi. p. 506.) It appears from Boutcher, that this mode of obtaining young birch trees, was formerly practised in Scotland.
In France and Germany, plantations of birch are frequently made by sowing the seed where the trees are intended finally to remain. For this purpose the poorest soils are harrowed in humid weather, in the month of October, or of November, and 15 lb. of seed, as it is taken from the catkins along with the scales, is sown on an acre, and afterwards covered with a bush harrow. Where the ground is under corn, the seed is sown with the last corn crop, as clover is in England; and, where it abounds with weeds and bushes, these are set fire to, early in the autumn, and the seed sown as soon afterwards as it is gathered from the trees. It is observed by Michaux, that burnt soil is peculiarly favourable to the growth of the birch, which in America reappears, as if by enchantment, in forests that have been burnt down.
Accidents, Insects, and Diseases. Pallas observes that, in some parts of Russia, where whole tracts of forests of different kinds of trees occur, there is scarcely any tree more frequently struck by lightning than the birch ; which, he says, refutes the superstitious notion of the Laplanders, who, believing that the tree is never struck by lightning, seek for shelter under its branches in a thunder-storm. It has constantly been observed, he says, that the birch is always struck by the electric fluid transervely, below the top, and shivered to pieces; while the pine is ploughed by a deep furrow from the apex to the ground, tearing off the bark, and leaving the tree entire. The common birch, Mr. Westwood observes, is a tree upon which a very great number of insects feed, seldom, however, causing any mischief of importance. Of these, it will be sufficient to notice a few of the more remarkable; indicating by a star those which not only feed on the birch, but on various other trees; and by a dagger those which feed on the birch only; commencing with the Lepidóptera, the caterpillars of which, either exclusively or partially, subsist upon its leaves. Amongst the butterflies, the Camberwell beauty (Vanessa Antiopa) is a partial birch-feeder, whilst the brown hair-streak butterfly (Thècla bétula) seems to be confined to birch woods ; appearing in the winged state in the month of August. Amongst the Sphingida, Smerinthus tiliæ (the lime hawk moth) occasionally feeds upon the birch. Amongst the Linnæan Bómbyces, the singular lobster caterpillar (Staúropus fàgi) partially feeds upon this tree, and is met with, though but rarely, at Birch Wood, in Kent.
* Leiocámpa dictæ'a and * L. dictæöides, * Lophópteryx camelina, * L. carmelita, * Ptilophora variegàta, * E'ndromis versícolor (the rare glory of Kent moth), the reputed British species * Aglaia tau, * Eriogáster lanéstris, * Callimorpha miniàta, * Lithòsia quádra. Amongst the Noctuidæ, * Apatèla leporina, * Acronýcta aurícoma, † Cerópacha fluctuosa, * C. flavicórnis (the caterpillar of which is a leaf-roller), * Cósmia trapetzina, + C. fulvàgo, * Brèpha nòtha, * Catocàla fráxini. Amongst the Geométridæ, * Hybérnia capreolària, * H. prosapiària, * H. defoliària, * Phigalia pilosària, * Bíston prodromàrius, * B. betulàrius, * Hipparchus papilionàrius, + Cabèra exanthémata, + Melanippe hastàta, + Emmelèsia heparàta. Amongst the smaller moths, +Platýpteryx lacertula, * Drépana falcatària, * D. unguícula, * Pýralis bárbalis, † Antithèsia betuletàna, Anacampsis betùlea, Agèria sphecifórmis (one of the small clear-winged hawk moths), and Zeuzèra æ’sculi (fig. 636. in p. 887.), feed upon the wood of the birch. The coleopterous insects, Balaninus bétulæ, Deporàus bétulæ, Rhynchìtes bétulæ, and Chrysomela bétulæ, also feed upon the birch in the larva state, and are found upon it when they have attained their imago form, devouring the tender leaves and young shoots. Several species of Tenthredínidæ, or saw flies, also feed upon the leaves whilst larvæ, including Selándria betulėti, and Lyda bétulæ. "The little flat hemipterous insect Aʼradus bétulæ resides beneath
1553 the bark, whilst A'phis bétulæ, Cóccus bétulæ, and Psýlla bétulæ subsist upon the young shoots and buds. When the birch begins to decay, various fungi root themselves into its wood. The principal of these are Dædàlea betulina Fries (Agaricus betulinus L., and our fig. 1553.), Polyporus betulinus Fries (Boletus betulinus Bull. t. 312.), and P. versícolor Fr. (our fig. 1554.); of these, P.betulious generally grows on the trunks of dead trees, and has white flesh, which has an acid taste and smell. The epidermis is very thin and delicate, and easily 1554 peels off; when dry the whole plant is very light, and its texture is between coriaceous and corky. (Eng. Fl., v. p. 140.) Polyporus fomentàrius (see Q. Robur) and P. nigricans Fries are also found on the birch. The latter, though called the black amadou, is quite unfit for making tinder. It is a very distinct species, and is of a bright shining black, though, when old, the epidermis becomes cracked, and of a dull ash colour. Rádulum orbiculare Fr. El., 1. p. 149. (Hýdnum rádula Fries Syst. Mus., 1. p. 423.; H. spathulàtum Grev. Fl. Edin., p. 406.) is found on the trunks of dead birches. Phlèbia radiàta Fries grows on the living birch
trees. This is a very singular fungus; it is composed of folds radiating from the centre, with a beautifully radiated margin; it was found at Appin, in Argyllshire. Sphæ'ria multiformis Fries is also found on the birch. To this list may be added Agáricus muscàrius L.
1555 (fig. 1555.), the fly agaric, the most poisonous of all the genus, which is generally found in birch woods. It is highly narcotic, producing, in small doses, intoxication and delirium, for which purpose it is used in Kamtschatka ; and, in larger doses, death. For a detailed account of its poisonous effects, see Roque's Hist. des Champ., p. 123. ; and a paper by Dr. Greville, in the 4th vol. of the Wernerian Trans., from which an extract is given by Dr. Lindley, Introd. to Nat. Syst. of Bot., p. 337. (Eng. Fl., vol. v. p. 4.)
Statistics. Recorded Trees. A weeping birch, at Ballogie, in the parish of Birse, in Aberdeenshire, measured, in 1798, 5 ft. in circumference at 4 ft from the ground. It had a clear straight stem, about 50 ft. high, of nearly equal thickness throughout; and the total height of the tree was supposed to be about 100 ft. (Stat. Hist., vol. ix. p. 129.) In the Forest of Tarnawa, in Morayshire, there are several birches which girt 9 ft, at 4 ft. from the ground. (Ibid., vol. viii. p. 557.) Sir Thomas Dick Lauder says that there are now many in the same forest which girt 10 ft. and 11 ft.; and he measured one which girted 13 ft. at 3ft. from the ground. (Lauder's Gilpin, vol. I. p. 288.) In France, in the time of Du Hamel, there was a superb weeping birch at Ermenonville, which stood beside the Temple of Philosophy, in the park, and hung over part of the building.
Existing Trees. In the environs of London, in the Fulham Nursery, 40 years planted, it is 50 ft. high. In Dorsetshire, at Melbury Park, 50 years planted, it is 72 ft. high ; in Wiltshire, at Wardour Castle, 40 years planted, it is 60 ft. high, diameter of the trunk 2 ft., and that of the head 30 ft. In Scotland, in Haddingtonshire, at Yester, 80 years planted, it is 73 ft high, diameter of the trunk 4 ft. 6 in., and of the
head 78 ft. ; in Forfarshire, at Kinnaird, 100 years planted, it is 70 ft. high, the diameter of the trunk 3 ft., and of the head 54 ft. ;' in Perthshire, at Taymouth,
B. alba péndula is 64 ft. high, the diameter of the trunk 2 ft., and of the head 50 ft. ; in Ross-shire, at Brahan Castle, the species is 70 ft. high, the diameter of the trunk 2 ft., and of the head 30 ft. In Ireland, in the Glasnevin Botanic Garden, 35 years planted, it is 36 ft. high, the diameter of the trunk 1 ft., and of the head 16 ft. ; in Tyrone, at Baron's Court, it is 60 ft. high, diameter
of the trunk 2 ft. 4 in., and
of the head 50 ft. In France, at Avranches, in the Botanic Garden, 19 years old, it is 49 ft high, the diameter of the trunk 24 ft., and of the head 20 ft. In Bavaria, in the Botanic Garden at Munich, 24 years planted, it is 28 ft. high. In Austria, at Vienna, at Laxenburg, 25 years old, it is 20 ft. high. In Prussia, at Berlin, at Sans Souci, 35 years old, the species is 50 ft. high, the diameter of the trunk 2 ft., and of the head 19 ft. In Sweden, at Lund, in the Botanic Garden, 52 ft high, the diameter of the trunk 9 in., and of the head 18 ft. In Denmark, at Rosenburg, it is between 70 ft. and 80 ft. high. In Russia, near St. Petersburg, at Rudets, on the estate of Madame Constantinoff, 40 years old, it is 71 ft. high, the diameter of the trunk 15 in. In Lombardy, at Monza, 24 years old, it is 45 ft. high, the diameter of the trunk 1 ft., and of the head 20 ft.
2. B. DÄU'RICA Pall. The Daurian Birch. Identification. Pall Ross., 1. p. 60.; Willd. Sp. Pl., 4. p. 463. ; Baum., p. 57. ; N. Du Ham., 3.
p. 204. ; Hayne Dend., p. 166. Synonymes. B. excélsa canadensis Wang. Beitr., p. 86.; Bouleau de Sibérie, Fr. Engravings. Pall. Ross., 1. t. 39.; Wind. Baum., 11.1.3. and 4. ; and our fig. 1556. Spec. Char., 8c. Leaves ovate, narrow at the base, quite entire, unequally
dentắte, glabrous. Scales of the strobiles ciliated on their margins; side lobes roundish. (Willd. Sp. Pl., iv. p. 463.). This species, according to Pallas, its discoverer, is closely allied to B. álba, and is found along with that species in Däyria, and part of Asiatic Siberia; but it is not found in European Siberia, nor in Russia. It does not grow so tall as the common birch, and the trunk does not exceed 1 ft. in diameter. The bark is grey, cleft longitudinally, and divided into brown scales, that have the appearance of being burnt. The branches are more subdivided, and more upright, than those of B. álba. The leaves are broader, commonly smaller, on shorter petioles, and unequally serrated. The stipules are lanceolate, grey, subpubescent, and deciduous. The male catkins are produced at the ends of the twigs of the foregoing year, two or three together, larger than in the common birch; the females are on the same twigs, lateral, thicker, with larger and more rounded 1556 scales; the seed, also, is a little longer ; but the mem
brane which surrounds it is narrower. The wood of the tree is hard, and yellower than that of the common birch. Pallas says that it differs from B. nigra L. (the red birch of America), in having smaller stipules, and in the leaves being less frequently, and never doubly, serrated; but, as he had only an opportunity of comparing it with a small dried specimen of the American species, of which he has given us a figure, we cannot place much confidence in his opinion. The young plants bearing this name at Messrs. Loddiges's have every appearance of being nothing more than a stunted variety of the common birch ; but these plants are too small and unhealthy to enable us to determine, with certainty, whether they are really of the kind described by Pallas, or not. This species was introduced in 1796 ; but it is not common in collections. There is a tree at Croome bearing this name, which, after being 30 years planted, is 40 ft. high. One in the Glasnevin Botanic Garden, 35 years planted, is 30 ft. high; and
one in the Botanic Garden at Munich, 25 years planted, is 20 ft. high. Variety.
B. d. 2 parvifolia Hayne Dend., p. 167., has the leaves smaller than the species.
* 3. B. FRUTICO'sa Pall. The shrubby Birch. Identification. Pall. Ross., 1. p. 62. ; Du Roi Harb. Baum., 1. p. 151. ; Willd. Sp. Pl., 4. p. 466.,
Baum., p. 61.; N. Du Ham., 3. p. 208.
Gesells. Naturf. Freunde, 5. p. 196., as quoted by Willdenow.
Female catkins oblong. (Willd. Sp. Pl., iv. p. 466.) This species is always shrubby, and never rises higher than 5 ft. or 6 ft., in moist situations; but, on mountains, it grows to a greater size, and the trunk attains a thickness of 2 in. or 3 in.
1557 The whole plant has a stunted appearance. The buds are numerous, and come out soon after those of B. álba. The leaves are small, and generally two from the same bud. They are lengthened out, and entire towards the petiole; and towards the end, which is very sharp, they are unequally serrated. The male catkins are sessile at the ends of the twigs, frequently unaccompanied with any leaf : they are more than 1'in. in length, and pendent. The female catkins are lateral from the leaf buds, solitary, alternate, upright, small, commonly peduncled, and accompanied by a small leaf; and the ripe seeds remain upon them during the winter ; their form is cylindric, and they are longer than those of B. nàna; the scales are narrow at the base, three-forked at the end; and there are three seeds to each scale, of the same size and form as in B, nàna. Pallas found this species in marshes, and on rocky mountains in the cold subalpine regions of Eastern Siberia. According to Willdenow, it is also found in Canada, and in Germany, in Bavaria, and Mecklenburg: About Berlin, it grows to the height of 4 ft. or 5 ft. It was introduced in 1818; and there are plants at Messrs. Loddiges's, and in some other collections.
* 4. B. PU'MILA L. The hairy dwarf Birch. Identification. Willd. Sp. Pl., 4. p. 467. ; Pursh Fl. Amer. Sept., 2. p. 622. ; N. Du Ham., 3. p. 207. ;
Lin. Mant, 124. Synonyme. B. nana Kalm Itin., 2. p. 263. Engravings. Jacq. Hort. Vind., t. 122. ; Du Roi Harb., 1. t. 3. ; Wang. Beitr., t. 29. f. 61. ; Dend.
Brit. t. 97, and our fig. 1558. Spec. Char., fc. Branches pubescent, without dots. Leaves roundish-ovate,
on long footstalks, densely clothed with hairs on the under surface. Female catkins cylindrical. (Willd. Sp. Pl., iv. p. 467.) A shrub, a native of bogs in
5. B. NÅ'NA L. The dwarf Birch. Identification. Lin. Sp. Pl., 1394. ; Willd. Sp. Pl., 4. p. 465. ; Fl. Br., 1012. ; Eng. Fl., 4. p. 154.;
Hook. Scot., p. 274. ; Dicks. H. Sicc., fasc. 8. 16. ; Ehrh. Arb., 18. ; Gagneb. Act. Helvet., 1. p. 58. ; Lind. Wicksb., 5. ; Hayne Dend., p. 168. ; Pursh Fl. Amer. Sept., 2. p. 22. ; Lodd. Cat., ed. 1836. Synonymes. B. nana Suecdrum Bromel. Chi. Goth., 11., Linn. Act. Suec., 1735, 15. ; B. No. 1629., Hall. Hist., 2. p. 300.; B. No. 259., Amm. Ruth., 180.; B. palustris pùmila, &c., Cels. Act. Succ.,
1739, 3. Engravings. Am. Acad., 1. t. 1. ; Eng. Bot., t. 2326. ; Fl. Lapp., ed. 2., t. 6. f. 4. ; Lightf., t. 25.;
Pall. Ross., 1. t. 40. f. D. G. ; Fl. Dan., t. 91. ; and our fig. 1559.
(Eng. Fl., iv. p. 154.) A bushy shrub, seldom exceeding 2 ft. or 3 ft. in
1559 the shoots grow to the length of 6 ft.; and, in a state of cultivation, they grow as high as 9 ft., and assume an erect form. This shrub is of singular use in the domestic economy of the inhabitants of Lapland. Its branches furnish them with their beds, and their chief fuel ; its leaves, with a better yellow dye than that obtained from the common birch; its seeds afford nourishment to the ptarmigan, or white partridge (Tétrao Lagòpus L.), which supplies a considerable portion of their food, and also forms an important article of commerce; and, for their medicine, it produces the fungus Polyporus fomentàrius Mich., respecting which some details will be found under the head of Quercus, sect. Robur, from which the moxa, or amadou, is prepared, and which the Laplanders consider an efficacious remedy in all painful diseases. Such is the wonderful power of adaptation of man, in a country possessing few natural resources. B. nàna has been in cultivation in Britain since the days of Miller, and is by no means unfrequent in collections. Price of plants, in the London nurseries, is 2s.
each; and of seeds, 6d. per packet. At New York, plants are 25 cents each. Varieties.
B. n. 2 stricta Lodd. Cat., ed. 1836, is somewhat more erect in habit
than the species. There are plants at Messrs. Loddiges's. Pallas men