|Trochodendron aralioides subsp. var.||Wheel Tree|
|File:Trochodendron aralioides 2.jpg||
Trochodendron is a genus of flowering plants with one living species Trochodendron aralioides and five extinct species known from the fossil record. It was often considered the sole genus in the family Trochodendraceae, though botanists now include the distinct genus Tetracentron in the family Trochodendraceae also. Trochodendron is native to Japan, southern Korea, Taiwan and the Ryukyu Islands with fossils know from North America and Europe.
Trochodendron aralioides is an evergreen tree or large shrub growing to 20 m tall. Trochodendron shares with Tetracentron the very unusual feature in angiosperms, of lacking vessel elements in its wood. This has long been considered a very primitive character, resulting in the classification of these two genera in a basal position in the angiosperms; however, genetic research by the Angiosperm Phylogeny Group has shown it to be in a less basal position (early in the eudicots), suggesting the absence of vessel elements is a secondarily evolved character, not a primitive one.
|Standard Cyclopedia of Horticulture|
Trochodendron (Greek, wheel and tree, alluding to the appearance of the fls., the anthers of the numerous spreading stamens forming a ring.). Trochodendraceae. Evergreen tree with aromatic bark and foliage, with alternate or whorled long-petioled lvs. and small fls. in terminal upright racemes: fls. long-pedicelled, perfect, without perianth; stamens numerous, filaments slender: carpels 6-10 in one whorl, connate below, with short linear spreading styles: fr. consisting of 6-10 follicles inserted below in the fleshy receptacle, dehiscent at the apex, with several linear seeds in each carpel. The tree is probably not in cult. in this country, but may be recommended for its handsome evergreen foliage for the middle and southern Atlantic states and for Calif. T. aralioides, Sieb. & Zucc. Tree, to 50 ft., or in cult. spreading shrub, glabrous: lvs. rhombic-obovate to elliptic-lanceolate, obtusely acuminate, crenate-serrate, lustrous and dark green above, lighter green beneath, 2-5 in. long; petioles 1-3 in. long: fls. green, 3/4 in. broad across the stamens; anthers yellow: fr. brown, 1/2 – 3/4 in. across. June. CH
Pests and diseases
- ↑ Pigg, K.B. (2001). "Trochodendron and Nordenskioldia (Trochodendraceae) from the Middle Eocene of Washington State, U.S.A.". International Journal of Plant Sciences 162 (5): 1187-1198. doi:10.1086/321927.