A tree 100 to 120 ft high in Japan, with a reddish-brown trunk 3 or 4 ft in diameter. Branches horizontal or depressed, bearing the successive ramifications in two opposite horizontally spreading rows. The final leaf-bearing subdivisions are, leaves and all, about 1⁄16 in. wide, and rather flattened. Leaves scale-like, not glandular, of two sizes, the lateral pairs the larger, about 1⁄12 in. long, somewhat boat-shaped, clasping the smaller ones above and beneath; all are blunt, thick, and fleshy, rich green above, paler beneath. The margin of every leaf beneath is defined by a thin line of glaucous bloom, which gives a variegated appearance. Cones solitary on a short branch, 1⁄3 in. diameter, brown; scales usually eight, the surface slightly hollowed towards the centre, where there is a small projection.
Native of Japan, and long cultivated there for its beauty and for its timber; introduced by John Gould Veitch in 1861. It yields the most valuable of Japanese timbers. As an ornamental tree in the British Isles it is very pleasing. It does not grow very fast, and the largest trees in the country are only about 70 to 80 ft high, but well-grown specimens are very graceful in their soft feathery branching. It likes a good moist soil, but will not thrive where there is much lime. With age and on poor soils it is apt to get thin, but this can to some extent be remedied by clipping off the ends of the shoots to induce denser branching – a process it bears very well. It is one of the favourite subjects of the Japanese for dwarfing. It is well distinguished from C. pisifera and C. lawsoniana by its blunt, round-ended leaves, and the thin glaucous line just beyond the margins beneath.
The biggest specimen so far recorded in the British Isles grows near to the National Pinetum, Bedgebury, Kent; this is 83 ft high on two stems, the thickest 81⁄2 ft in girth (1966). The handsomest specimen found by A. F. Mitchell also grows in Kent; this is at Benenden, and measures 70 × 61⁄2 ft (1958). Others recorded are: Bicton, Devon, 71 × 71⁄4 ft (1957); Killerton, Devon, 68 × 71⁄2 ft (1964); Westonbirt, Glos., 67 × 41⁄2 ft (1963); Petworth House, Sussex, 77 × 43⁄4 ft (1961).
Numerous varieties are in cultivation, of which the following are the most important:
cv. ‘Aurea’. – Young shoots golden yellow. A Japanese garden tree, introduced by Fortune in 1860. There is an example in the Italian Garden at Bicton, Devon, measuring 52 × 6 ft (1957).
cv. ‘Nana’. – A very slow-growing bush, ultimately 3 ft or so high and more wide; leaves lustrous blackish green; sprays concave, arranged in horizontal tiers. Introduced from Japan by Siebold.
cv. ‘Nana Gracilis’. – One of the finest medium-dwarf conifers, growing 8 to 10 ft high; foliage blackish green. A tree of great individuality, with a rugged aspect.
cv. ‘Crippsii’. – Coloured similarly to ‘Aurea’, but of a richer shade; very pleasing as a small tree of dense, very elegant habit. Raised by Cripps’ nursery, Tunbridge Wells, around the turn of the century. The largest tree recorded was planted at Tilgate, Sussex, in 1905 and now measures 50 × 41⁄4 ft (1961). There are several other examples in the south of England approaching that size, e.g. Westonbirt, Glos., 42 × 23⁄4 ft (1966), and Nymans, Sussex, 44 × 31⁄2 ft (1966).
cv. ‘Filicoides’ – Habit dense; branching very close, the ultimate divisions short, much crowded, and not so flattened as in the type. Introduced from Japan by J. G. Veitch in 1861. An old specimen at Scorrier House, Cornwall, is 47 ft high with a girth of 41⁄4 ft (1959). One at Wakehurst Place, Sussex, measures 35 × 21⁄2 ft (1964).
var. formosana (Hayata) Rehd. – A tree to 125 ft found in the northern and central part of Formosa. It differs from the Japanese type in the leaves, cones, and seeds being smaller.
cv. ‘Lycopodioides’. – Branching irregular, not strictly in two rows, the ultimate branchlets much thicker, more four-sided, and less compressed than in the type. Like many Japanese plants, it was introduced almost simultaneously (in 1861) by Fortune and by J. G. Veitch. Although often stated to be of dwarf habit, there are specimens ranging from 37 to 46 ft in height at: Westonbirt, Glos.; Scorrier House, Coldrenick, and Tregrehan, Cornwall; Bicton, Devon; Nymans, Sussex; Linton Park, Kent; and Wansfell, Ambleside, Westm.
cv. ‘Sanderi’. – A curious little shrub of rounded, dense habit, with stiff, spreading, awl-shaped leaves, 1⁄8 to 1⁄6 in. long, of a very glaucous blue tint, and borne in decussate pairs. It was put into cultivation by Sander’s nursery as “Juniperus sanderi”, but originated in Japan and does not appear to be a juniper. Masters and Beissner were both of the opinion that it is a juvenile state of C. obtusa.
cv. ‘Tetragona Aurea’. – This has the branching of ‘Filicoides’, but the branchlets are thicker, more four-sided, and scarcely compressed. Young shoots yellow. Although slow-growing it is by no means dwarf as the following measurements show: Bicton, Devon, 36 × 2 ft (1967); Sindlesham, Berks., 30 × 11⁄2 ft (1959); Nymans, Sussex, 29 × 3 ft (1966); Wakehurst Place, Sussex, 27 × 11⁄2 ft (1965); Leonardslee, Sussex, 25 × 13⁄4 ft (1962). Its rate of growth is suggested by a tree in the National Pinetum, Bedgebury; planted in 1925 it measures 13 × 3⁄4 ft (1966).