Trochodendron
Wheel beam ( Trochodendron aralioides )
The wheel beam ( Trochodendron aralioides ) is the only species of the monotypic genus therefore Trochodendron in the family Trochodendraceae. It is Japan, home to the Ryukyu Islands and Taiwan.
- 4.1 Literature
- 4.2 Notes and references
Description
Appearance and leaves
The wheel beam grows as evergreen tree that reaches the stature heights of up to 20 meters, but remains considerably lower in culture generally, or he grows as a shrub. All plant parts are bare. The protruding branches have a brown or gray bark.
The leaves are alternate and almost tufted at the ends of branches. The petiole is 3-7 inches long. The leathery, simple leaf blades are rhombic- ovate, with a length of about 6 to 12 inches and a width of 2.5 to 7 centimeters to obovate with a blunt or tapered at the top. On each side of the midrib five to seven lateral veins are formed. The base is wedge-shaped, serrated leaf margin glandular. The upper leaf surface is dark green and glossy, the lower leaf surface is brighter than the top. Stipules absent.
Flowers
The flowering period extends from May to June. Ten to twenty flowers are borne in terminal, slightly branched, racemose inflorescences, which have a diameter of 5 to 13 centimeters. The flower stems are 1.5 to 3.5 inches long.
The greenish, hermaphroditic flowers have a diameter of up to 18 mm and have no perianth. At the edge of a broad green discus are from 40 to 70 4.5 to 5 millimeters long stamens. The anthers are long and yellow. The four to eleven carpels are fused together laterally.
Fruit and seeds
The four to eleven -seeded follicles are united at the base with the floral axis to a dark gray multiple fruit that has a diameter of 7 to 10 millimeters. The brown or black seeds are 1.5 to 2 or 3 to 3.5 millimeters long and spindle-shaped.
Chromosome number
The chromosome number is.
Distribution and habitat requirements
The distribution area of Radbaumes extends over Taiwan, Japan and the Ryukyu Islands. There he grows in evergreen forests or steppes and dry forests on moderately nutrient-rich, mildly acidic to mildly alkaline, sandy- loamy to loamy soils at altitudes 300-2700 m. It prefers light shade to partial shade, is moderately frost -resistant and heat -loving.
System
Trochodendron aralioides is the only species of the monotypic genus therefore Trochodendron in the family Trochodendraceae. There is only one other genus, Tetracentron counted to the family, which is also monotypic.
The genus name Trochodendron derives from the Greek words " trochos " for cycling and " dendron " for tree. " Trochos " drawing attention to the annularly arranged stamens. The specific epithet refers to the aralioides resemblance to some species of the genus Aralia.