[Illustration:  LEAVES OF CARPINUS BETULUS INCISA.]

It hardly seems necessary to dwell upon the value of the hornbeam as a hedge or shelter plant.  In many nurseries it is largely used for these purposes, the russet-brown leaves remaining on the twigs until displaced by the new growths in spring.

Var. incisa (Aiton, “Hortus Kewensis,” v., 301; C. asplenifolia, Hort.; C. laciniata, Hort.).—­These three names represent two forms, which are, however, so near each other, that for all practical purposes they are identical.  A glance at the accompanying figure will show how distinct and ornamental this variety is.

[Illustration:  HORNBEAMS (ONE WITH INOSCULATED TRUNK).]

Var. quercifolia (Desf. tabl. de l’ecol. de bot. du Mus. d’hist. nat., 213; Ostrya quercifolia, Hort.; Carpinus heterophylla, Hort.)—­This form, as will be seen by the figure, is thoroughly distinct from the common hornbeam; it has very much smaller leaves than the type, their outline, as implied by the varietal name, resembling that of the foliage of the oak.  It frequently reverts to the type, and, as far as my experience goes, appears to be much less fixed than the variety incisa.

Var. purpurea (Hort.).—­The young leaves of this are brownish red; it is well worth growing for the pleasing color effect produced by the young growths in spring.  Apart from color it does not differ from the type.

Var. fastigiata (Hort.).—­In this variety the branches are more ascending and the habit altogether more erect; indeed, among the hornbeams this is a counterpart of the fastigiate varieties of the common oak.

Var. variegata, aureo-variegata, albo-variegata (albo-marmorata).—­These names represent forms differing so slightly from each other, that it is not worth while to notice them separately, or even to treat them as distinct.  In no case that I have seen is the variegation at all striking, and, except in tree collections, variegated hornbeams are hardly worth growing.

[Illustration:  FULL GROWN HORNBEAM IN WINTER.  CARPINUS BETULUS (Full grown tree at Chiswick, 45 ft. high in 1844).]

Carpinus orientalis[2] (the Oriental hornbeam) principally differs from our native species in its smaller size, the lesser leaves with downy petioles, and the green, much-lacerated bractlets.  It is a native of the south of Europe, whence it extends to the Caucasus, and probably also to China; the Carpinus Turczaninovi of Hance scarcely seems to differ, in any material point at any rate, from western examples of C. orientalis.  According to Loudon, it was introduced to this country by Philip Miller in 1739, and there is no doubt that it is far from common even now.  It is, however, well worth growing; the short twiggy branches, densely clothed with dark green leaves, form a thoroughly efficient screen.  The plant bears cutting quite as well as the common hornbeam, and wherever the latter will grow this will also succeed.