This section is from the book "Handbook Of Hardy Trees, Shrubs, And Herbaceous Plants", by W. Botting Hemsley. Also available from Amazon: Handbook of hardy trees, shrubs, and herbaceous plants.
Noble evergreen trees with rigid scattered and clustered leaves and erect oblong or oval cones rounded at the top. Scales of the cones broad, thin, coriaceous, entire, closely appressed, at length deciduous. Seeds winged. The species or forms are natives of the Atlas, Syrian and North Indian mountains. Dr. Hooker, who has had opportunities of observing them in their native countries, pronounces them to be forms or races of one species, whilst other accomplished botanists consider them entitled to specific rank. Whichever view we take of the matter is of little importance, because they are sufficiently distinct in the young state at least to be easily recognised. The ancient name of the Syrian tree.
1. C. Libani. Cedar of Lebanon (fig. 218). - A majestic branching tree with short rigid deep dark green leaves and oblong oval pedunculate purplish ultimately brown cones from 3 to 4 inches long, remaining on the tree several years. Scales with a somewhat membranous margin, separating tardily from the axis. This species was introduced nearly two centuries ago, and there are now many hundreds of fine specimens in various parts of the country. It is perfectly hardy, producing its cones and ripening its seeds as freely as in its native habitats, where, by-the-by, it is gradually becoming very rare. It has been found on Mounts Lebanon, Taurus and Aman. There is a diminutive form called nana, and the variety argentea has silvery foliage.
Fig. 218. Cedrus Lilani.
2. C. Atlantica, syn. C. Africana and C. argintea. African or Silver Cedar. - It is difficult to find distinctive characters for this and the foregoing, but the main difference lies in the foliage, which in this is shorter, usually less than an inch in length, and of a glaucous green or silvery hue. It is a large tree, from 80 to 120 feet high, of more erect pyramidal habit than that commonly assumed by the Lebanon Cedar in this country, rarely producing thick branches like the latter. It forms almost exclusively the arborescent vegetation of the upper plateaus of the Atlas mountains. It has been stated by M. Jamin that this and the foregoing are associated at Fougour, and that the Silver Cedar ripens its cones earlier than C. Libani. But this will be accepted with considerable doubt when we remember that the cones are two or three years coming to maturity, and that the same tree does not produce cones every season.
3. C. Deodara. Deodar or Indian Cedar. - A pyramidal tree when young, with dense slender drooping branches thickly clothed with glaucous green leaves. In the young stage the Deodar is readily distinguished by the foregoing characters added to the longer leaves; but according as the tree becomes older, these distinctions are less apparent, though perhaps never entirely obliterated. The cone of this form is said to shed its scales as soon as mature. This is undoubtedly one of the most elegant and graceful members of this beautiful order, and is now planted by hundreds of thousands. There are two or three rather striking varieties. C. Z. robusta has coarser larger leaves and thicker branches; C. D. crassifolia has short thick rigid foliage; and C. D. viridis or tenuifolia is of slender habit, with bright green foliage. This species is a native of the mountains of North India, where it forms vast forests up to an elevation of 12,000 feet. It attains a height of 100 to 150 feet, with a girth of 20 to 30 feet. It was introduced into England in 1822.
Cunninghamia Sinensis, the only known species of its genus, is a lofty evergreen tree with sessile lanceolate-acuminate coriaceous leaves, somewhat in the way of an Araucaria. Cones rather small, ovate, remarkable in having small almost obsolete scales, and large leafy toothed bracts. A native of China, and too tender for any but the most favourable localities in this country.
Arthrotdxis is a small genus of Australasian evergreen dioecious shrubs with small scale-like leaves and small globular cones of imbricated scales with from 3 to 5 carpels under each scale. None of the species are hardy enough to withstand our ordinary winters.