The genus Thuja - the Arbor-vitae
A genus of six species. Leaves scale-like, decussate, lateral pairs keeled, facial pairs flattened. Cones, ovoid-oblong with 8 to 12 thin leathery to woody scales, maturing in one season (cf. Cupressus). Branchlets flattened.
(T)
Thuja dolabrata, L. (Thujopsis dolabrata Sieb. & Zucc.)
Hiba
Native in Japan where it grows to a height of 80 feet and is a valuable timber tree. Introduced into this country in 1853, it has proved a useful ornamental shrub in the milder and moister parts. It does well in the South-West peninsula and is one of our most effective evergreen shrubs. The plant has a broad pyramidal habit with ascending branches. The flat branchlets are spread horizontally. Leaves opposite, curved, acute, lustrous dark green and with conspicuous white stomatal patches beneath.
(A)
Thuja occidentalis, L.
American Arbo-vitae
Native to Eastern North America from Nova Scotia to Virginia where it attains a height of 60 feet. One of the earliest, if not the first American tree to be introduced into Europe as it was brought back by the members of the Cartier expedition which discovered the St. Lawrence River. It is widely distributed in its native habitats where it forms dense forests in swampy regions. Introduced in 1596 in this country, where it does not grow very large. It has been widely planted as an ornamental tree, as a windbreak and as a hedge plant. It has a pyramidal habit: its dark green foliage has conspicuous glands on the leaves of the main axis and a peppermint smell.
(A)
Thuja orientalis, L. (Biota orientalis End.)
Chinese Arbor-vitae
Indigenous in North and West China where it grows to 40 feet, it forms a tree with erect branches quite distinct among the Thujas. Introduced into this country c. 1740, it has been much planted though it is liable to damage on exposed sites. The cones are ovoid, nearly one inch long, glaucous at first, and with six to eight woody scales, each with a hooked tip. Its foliage has only a faint aroma.
(A)
Thuja plicata, D. Don
Western Arbor-vitae
Native in Western North America, especially in the region of British Columbia, Oregon and Washington, where it attains a height of 200 feet and is a valuable timber tree. Its light-weight timber is known as Western Red Cedar and is much used commercially. Its wood is durable when in contact with the soil and is also much used for roof shingles. Introduced by Messrs. Veitch in 1853, it has been very widely planted both as an ornamental tree and for hedges. Its natural habit is markedly pyramidal and the buttressed trunk has ascending branches at the base. The aromatic leaves are bright green on the upper side and with white lines on the lower, The erect cones are rather narrow with up to ten woody scales.