The Trees of Great Britain & Ireland/Volume 3/Corylus

by Henry John Elwes and Augustine Henry

 

CORYLUS

 

Corylus, Linnæus, Sp. Pl. 998 (1753); Bentham et Hooker, Gen. Pl. iii, 406 (1880); Winkler, in Engler, Pflanzenreich, iv, 61, Betulaceæ, 44 (1904).

 

Deciduous trees or shrubs, belonging to the order Betulaceæ. Leaves alternate, distichous on the branchlets, stalked, simple, penninerved, doubly serrate; stipules two, caducous. Buds composed of numerous imbricated scales, corresponding to stipules.

Flowers monœcious, arising from buds on the branchlets of the previous year. Male flowers in cylindrical catkins, appearing in autumn; fascicled, or two to five on a common peduncle; composed of numerous imbricated bracts, each bearing on its inner side two partly adnate bracteoles and four stamens, without a perianth; filaments bifid, each branch bearing a single anther cell, tufted with hairs at its apex. Female flowers in buds resembling those which contain leaves only, but distinguishable in spring by the projecting styles. The lower scales of the buds bear leaves in their axils, the flowers, few in number, arising only in the axils of the uppermost scales, each scale bearing two flowers. Each flower, surrounded at the base by two minute bracteoles, more or less deeply cut and forming an involucre, consists of a two-celled ovary, surmounted by a short, denticulate perianth and two long styles; each cell containing one ovule.

Fruit, in clusters at the end of the short leafy branch into which the bud has developed; a one-celled, one-seeded nut, the remains of the other cell and ovule, which have aborted, being visible in its upper part. The nut is contained in a leafy involucre, open at the summit, and variously lobed or dentate. Seed without albumen; cotyledons thick, fleshy, containing oil, remaining on germination underground.

Eight or nine species of Corylus are known, all natives of northern temperate regions, and mostly shrubs or small trees. Only one species, Coryus Colurna, attains the dimensions of a timber tree, and comes within the scope of our work.

 

CORYLUS COLURNA, Constantinople or Turkish Hazel

 

Corylus Colurna, Linnæus, Sp. Pl. 999 (1753); Loudon, Arb. et Frut. Brit. iii. 2029 (1838); Willkomm, Forstliche Flora, 377 (1887); Winkler, op. cit. 50.

 

A tree of moderate size, attaining 60 to 80 feet in height and 7 to 8 feet in girth of stem. Bark of trunk grey, thick, and scaling off in small irregular plates. Twigs brittle, the young shoots glandular pubescent, those of a year old glabrous and brown in colour, the bark of older shoots becoming corky. Leaves 3 to 5 inches long by 2 to 4 inches wide, broadly oval, ovate, or obovate, deeply cordate at the base, acuminate at the apex, doubly serrate or with large serrate teeth, dark green above, lower surface lighter green and sparingly pubescent, with glandular hairs on the principal nerves and midrib; nerves usually eight pairs; petiole 4 to 1 inch long, glandular pubescent or glabrescent. Catkins^[1] 1½ to 3 inches long. Fruits crowded, three to ten in number, long, compressed, pubescent towards the apex. Involucres tomentose with intermixed glandular hairs, deeply and irregularly divided into linear, acute, stiff, long-pointed segments, which are either entire or toothed, exceeding in length two to three times the nut.

 

Seedling

The germination resembles that of the oak, the cotyledons, which are shortstalked, plano-convex and obovate, remaining in the seed and not being carried above ground. Caulicle stout, terete, tapering, ending in a long tap root with numerous branching fibres. Stem stout, terete, covered with numerous scattered glandular hairs, giving off an inch above the cotyledons a pair of opposite leaves, which are about 2 inches long, broadly ovate, acute at the apex, cordate at the base, with three to five pairs of lateral lobes, unequal in size, toothed and ciliate in margin; petiole ¾ inch, glandular-pubescent. Succeeding leaves are alternate and larger in size.

 

Varieties

In addition to the typical form described above, several geographical varieties occur, as the species is distributed over a wide area.

1. Var. glandulifera, A. de Candolle, Prod. xvi. 2, p. 132 (1864).—Occurs with the type in Europe and western Asia. In this variety the pubescence on the petioles, peduncles, and fruit-involucres is intermixed with glandular bristles; and the segments of the involucres are less acute and often dentate.

2. Var. lacera, A. de Candolle, op. cit. 131 (Corylus lacera, Wallich, List, 2798). —Leaves obovate, larger, up to 7 inches long, with ten to twelve pairs of nerves. Involucre-segments linear-lanceolate with glandular hairs. This variety occurs in the western Himalayas, from Kashmir to Nepal, at elevations of 6000 to 10,000 feet, and in many places is gregarious. Sir George Watt informs me that it is a handsome tree, usually growing in the mixed forests, and often attaining 80 feet in height.

3. Var. chinensis, Burkill, Journ. Linn. Soc. (Bot.) xxvi. 503 (1899) (Corylus chinensis, Franchet, Journ. de Bot. 1899, xiii. 197).—Leaves large, up to 7 inches long, with ten to twelve pairs of nerves, broadly ovate, unequal, acuminate; petioles bristly. Involucres striate and constricted above the fruit, lobes forked, lobules acute and falcate. This variety occurs in China, and grows to about 40 feet high in mixed forests in Yunnan, Szechwan, and Hupeh.

Apparently no varieties have originated in cultivation, but a hybrid has been obtained between this species and the common hazel, viz.:—

Corylus intermedia, Loddiges, Catalogue (1836) (Corylus avellana × Corylus Colurna, Rehder, Mitth. Deuts. Dendrol. Gesell. 1894, p. 43).—This is a tall shrub or small tree with the bark of the common hazel, i.e. darker and less scaly and fissured than that of C. Colurna. The fruit resembles that of the last species, but is shorter and scarcely glandular. Specimens of this are growing in the Botanic Gardens of Jena and Gdttingen and in the Forestry Garden at Münden, but we know of none in England.

 

Identification

In summer the Turkish hazel is readily distinguishable by the scaly bark and the obovate leaves deeply cordate at the base and distichously placed on the branchlets. In winter (Plate 126, Fig. 6) the following characters are available -—Twigs: brittle, shining, brownish-yellow, with few and inconspicuous lenticels and scattered glandular pubescence, usually, however, dense near the base of the shoot, which is ringed with the scars of the previous season's bud-scales, one or two of the lowermost scales often persisting dry and darkened in colour; second year's shoot with corky bark, which fissures and exfoliates slightly. True terminal bud absent, a small oval scar at the apex of the twig, on the side opposite to the highest leaf-scar, indicating where the tip of the shoot fell off in summer. Leaf-scars semicircular with three to six bundle-dots,^[2] somewhat obliquely set on prominent pulvini. Stipule-scars small, transverse, lunate, one on each side of the leaf-scar. Buds pretty uniform in size, alternate and distichous on the twig, from which they arise at a wide angle, ovoid, rounded at the apex; scales about ten, imbricated, pubescent, ciliate in margin. Pith small, circular. Male catkins present in winter on flower-bearing trees.

 

Distribution

The Turkish hazel has a wide distribution, extending from south-eastern Europe, through Asia Minor and the Caucasus, to the Himalayas and Western China. In Europe it is found growing wild in Banat, Slavonia, Herzegovina, Bosnia, Servia, Roumania, and Greece.^[3] In Banat, according to Willkomm, it sometimes forms pure woods in the mountains; and in Northern Albania it ascends as a bush to 3000 feet altitude.^[4] It occurs in Asia Minor in Bithynia, Paphlagonia, and Anatolia. According to Radde,^[5] it grows in small groups on the south side of the main chain of the Caucasus and in many localities in Georgia, at 3500 to 5000 feet elevation, where it is a stately tree 50 to 70 feet in height, and with a stem diameter of 18 inches. The nuts of the wild tree are small, with a thick and hard shell. It also grows in the mountains of Karabagh, but does not occur in the Talysch district. (A.H.)

 

Cultivation

The Turkish hazel was first cultivated in western Europe by Clusius, who obtained it from Constantinople in 1582. Linnæus states that in 1736 the finest specimen known was a tree in the Botanic Garden at Leyden, which had been planted by Clusius. It was apparently first cultivated in England about the year 1665 by John Rea,^[6] who states that he had then "many goodly trees of the filbeard of Constantinople." He grafted these upon ordinary hazel stocks.

The Turkish hazel is now a rare tree in England, seldom to be got from a nursery, though perfectly hardy and easy to grow from seed, which it ripens in most seasons in the southern half of England. I have raised many from a tree at Tortworth Court, and the Earl of Ducie has done the same. The seed usually germinates in the following spring if sown when ripe, but if kept till spring, sometimes not until the next year. The seedlings, on my soil at least, have more inclination to become bushes than to make a single stem, but, if cut down two or three years after planting, will throw up strong suckers which may be trained into a tree, and should be planted in half-shady places or in an opening in a wood, as they are liable when young to be injured by spring frosts.

 

Remarkable Trees

No other place can show so many fine trees as Syon, where there are in the grounds at least five, all apparently of about the same age. The largest of these stands near the east bridge over the lake, and is about 75 feet high, with a bole about 30 feet long and 6 feet 9 inches in girth. Near the gardener's house is another fine tree more spreading in habit, about 70 feet by 7 feet 6 inches, which is probably not the same as one figured by Loudon, which was then 61 feet high. This has been figured by the Hon. S. Tollemache as the Hazel.^[7]

At Bute House, Petersham, Henry measured a well-shaped tree which, in 1904, was 56 feet by 6 feet 7 inches.

At Corsham Court there is a remarkable tree about 50 feet high, which divides near the base into two stems, one of which is quite decayed, and the other, which has the appearance of having originated as a sucker from it, is quite sound and 6 feet 8 inches in girth. Lord Methuen tells me that he can remember this tree as formerly producing fruits which were sent up to table, but now it no longer bears any nuts.

At White Knights I saw a grafted tree from which seedlings had sprung up in the shrubbery, and one of these, growing at the base of a stump, is 10 feet high at about ten years old.

At Arley Castle there is a good tree which, in 1904, was by Mr. Woodward's measurement 60 feet by 5 feet 7 inches.

At Wollaton Hall, near Nottingham, the property of Lord Middleton, there is a tree 43 feet high which at 5 feet girths 7 feet 10 inches, and at 10 feet, where it forks, 8 feet. It has a spread of not less than 78 feet, which for this tree is very unusual (Plate 147). It is perhaps the most symmetrical of its kind that I have seen anywhere. In the Botanic Gardens at Oxford and Kew there are fair-sized specimens.

In Scotland and Ireland we know of no trees of great size, and none were recorded by Loudon; but at Glasnevin there is one about 35 feet in height, which divides into three stems close to the ground, and has very pendent wide-spreading branches.

 

Timber

Little or nothing is known of the timber in England, but a wood has been imported to France under the name of "Noisetier," which I believe to belong to this species, and which, as exhibited by M. Hollande of Paris, is very handsome. I purchased some very handsome veneer from Mr. Witt of London, which he told me had come to him direct from Constantinople, and which I believe was cut from the root of C. Colurna. Two good-sized logs of this tree were in the collection of Servian timbers shown at the Balkan States Exhibition in London in 1907; one of them is now in the Kew Museum. Gamble^[8] says that in the Himalaya it is a wellgrained timber, which does not warp, of a pinkish-white colour, and often shows a fine shining grain resembling that of bird's-eye maple.(H.J.E.)

 

 

Plate 147: Corylus Colurna at Wollaton Hall

Plate 147.

CORYLUS COLURNA AT WOLLATON HALL

 

1. Abnormal male flowers with enlarged bracteoles are figured in Gard. Chron. xxvi. 691, fig. 135 (1886).
2. The cicatrices left by the leaf-bundles on the leaf-scar are very irregular in number and shape, being circular dots or curved lines.
3. In Thessaly and Acarnania, according to Halacsy, Consp. Fl. Græcæ, iii, 135 (1904).
4. Beck, Veg. Illyrischen Lander, 300 (1901).
5. Pflanzenverb. Kaukasusländ. 187 (1899).
6. Flora, 225 (1665).
7. British Trees with Illustrations, 9 (1901).
8. Man. Indian Timbers, 684 (1902).