A genus of conifers comprising about a dozen species of hardy evergreen trees or shrubs, natives of America and Asia, two of them being indigenous to the Pacific Coast. Thuya gigantea, one of the Coast species, is a tall handsome evergreen graceful tree of pyramidal habit with somewhat drooping branches, and grows, under favorable circumstances, from one hundred to two hundred feet high with a diameter of stem from three to six feet, thriving well in any well-drained garden soil.
Propagate by seeds sown one-eighth of an inch deep in boxes filled with light sandy soil in a cold frame in early Spring. Transplant them into open nursery rows when they are three inches high, and plant them in their permanent quarters when they are about two feet high.
The Chinese species (Thuya orientalis), of a dwarf habit, is much used in cemeteries and formal gardens, its formal symmetrical habit making it a favorite in that style of gardening. Thuya occidentalis, the eastern species, grows to a height of about sixty feet and forms a narrow pyramidal rather compact head.
The different species have many garden varieties, and a number of them, including variegated forms, are very beautiful. These are propagated by cuttings placed in sand in a cold frame in the Fall or by grafting on the original species in early Spring.
Thuyopsis dolabrata This small genus comprises only a few species natives of Japan. Their foliage is much like that of the Thuya but the habit is spreading and more open. They make handsome rock-work plants. They grow easily in any garden soil.
Propagate by cuttings placed in a cold frame in sandy soil mixed with leaf-mold, in October.