A tree up to 70 or 80 ft high, with a trunk sometimes 7 ft or more in girth, covered with pale scaling bark; young shoots yellowish at first, glandular downy.
Leaves 21⁄2 to 6 in. long, 2 to 41⁄2 in. wide; broadly oval, obovate or ovate, pointed (sometimes abruptly) at the apex, heart-shaped at the base, coarsely double-toothed or almost lobed; upper side dark green, lower one downy along the midrib and veins; stalk 1⁄2 to 1 in. long, glandular-downy at first, afterwards glabrous. Male catkins 2 to 3 in. long. Nuts 1⁄2 to 5⁄8 in. diameter, the husk (involucre) in which it is set 11⁄2 in. across, fringed with numerous narrow pointed lobes 1⁄2 to 1 in. long, covered with a fine down freely mixed with which are gland-tipped bristles. The nuts are closely clustered three or more together. Bot. Mag., t. 9469.
Native of S.E. Europe and Asia Minor; introduced to England about the middle of the sixteenth century. There are some fine specimens in old English gardens, notably at Syon House, near Brentford, where there is an old specimen measuring 60 × 91⁄4 ft (1967). Others recorded recently are: Bicton, Devon, 55 × 111⁄4 ft at 11⁄2 ft (1959); Oxford Parks, 58 × 81⁄4 ft (1965); Wakehurst Place, Sussex, 48 × 31⁄2 ft and 45 × 3 ft (1964-5); Cambridge Botanic Garden, 45 ft with a spread of 66 ft (1967); Edinburgh Botanic Garden, 61 × 53⁄4 ft (1968).
The tree is well worth growing for its stately form, so remarkable for a hazel, and for its curiously enveloped nuts. It thrives very well in the hot summers and cold winters of Central Europe, and there usually has a short trunk with the bottom branches touching the ground, the whole tree forming a lofty pyramid. There are trees of this character at Schönbrunn, near Vienna. The height of these, 70 to 80 ft when this work was first published in 1914, is now over 100 ft. The tree in the Berggarten near Hanover, also mentioned in previous editions, died recently; the skeleton, which has been left in situ, shows a well-developed central stem with main branches springing from the base and almost equal to it in thickness.
C. jacquemontii Decne. C. lacera Wall. – This is the Himalayan representative of C. colurna. It differs from that species chiefly in the husk of the nut having few or no glandular bristles mixed with the down, and in the leaves being more distinctly obovate and sharply lobed and toothed. It thrives well at Kew, where there is a specimen measuring 44 × 41⁄2 ft (1960), which frequently bears good seed. Fruiting and flowering sprays from this tree are figured in Bot. Mag., n.s., t. 391.