A large, spreading shrub growing in cultivation to about 15 ft in height and almost twice as much across; branchlets slightly hairy when young, with a few long lenticels. Winter buds very large and distinct, bright glossy green, narrowly ovoid and pointed, with ciliate scales; on vigorous shoots the buds are 1⁄2 in. long. Leaves ovate to roundish, 2 to 4 in. long, 1 to 3 in. wide; rounded or slightly heart-shaped at the base, pointed, irregularly toothed; dark green above, and glabrous or with a few hairs only on the midrib and the eight to eleven pairs of sunken veins, which are also slightly hairy beneath; stalk 1⁄4 to 1⁄2 in. long, hairy. Fruit-catkins stalked, erect, 1 to 11⁄2 in. long; scales 1⁄3 in. long, with some hairs on the margins, the middle lobe twice as long as the side ones. Seeds with narrow wings. Bot. Mag., t. 9569.
Native of the Caucasus at sub-alpine elevations; introduced to Kew from Tiflis in 1897 and put into commerce by Späth of Berlin in 1906. It makes a handsome bush with alder-like leaves and is very striking in winter with its glossy, pale brown stems and large buds. The leaves usually die off a light yellow. The largest specimen recorded grows at Mount Usher in Co. Wicklow, Eire; it is 15 ft high and 27 ft across (1966). The specimen at Kew, referred to in the Botanical Magazine under the number cited, died in 1959; it was about 12 ft high and 15 ft across.
B. megrelica Sosn. – This birch, also a native of the Caucasus, was described as late as 1930. It is allied to the preceding but differs in its tree-like habit and in its leaves, which are more ovate in shape, 11⁄4 to 3 in. long, 2⁄3 to 21⁄4 in. wide, rounded to slightly heart-shaped at the base and gradually narrowed at the apex (but more rounded in outline on short shoots). Probably not yet introduced.
From the Supplement (Vol. V)
specimens: Wakehurst Place, Sussex, 26 ft high with a spread of 39 ft (1974); Aldenham Park, Herts., 40 × 31⁄2 ft with a 5 ft bole (1976); Westonbirt, Glos., in Victory Glade, pl. 1939, 31 × 23⁄4 ft at 1 ft (1978); Talbot Manor, Norfolk, pl. 1943, 26 × 13⁄4 ft (1978); Thorp Perrow, Bedale, Yorks., pl. c. 1930, 30 × 21⁄2 ft and 33 × 21⁄4 ft (1981).
B. megrelica – This species was introduced to Britain recently by means of seed received from the Moscow State University.