Isu Tree
Distylium racemosum
Family: Hamamelidaceae
What it is like
Distylium racemosum is an evergreen Shrub growing to 2 m (6ft) by 3 m (9ft) at a slow rate. See above for USDA hardiness. It is hardy to UK zone 8 and is frost tender. It is in leaf all year, in flower from March to April, and the seeds ripen from June to August. The species is hermaphrodite (has both male and female organs). Suitable for: light (sandy) and medium (loamy) soils and prefers well-drained soil. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils. It can grow in semi-shade (light woodland). It prefers moist soil.
Height (m): 2
Where it is found
Evergreen oak forests. Forests at elevations of 1000 - 1300 metres in Fujian, Hainan, Taiwan and Zhejiang Provinces of China.
E. Asia - China, Japan.
Conservation Status:
Countries/locations it is found in
How it is used
Food
Rating: 0
Medicine
Rating: 0
Other
Rating:
The ashes of the wood are used in glazing porcelain. Wood - hard, fine-grained, dark brown. A very valuable wood, it is used for small articles, musical instruments etc.
Wood: A list of the trees and shrubs that are noted for having useful wood.
How it is grown
Prefers a sandy soil. A lime tolerant plant, but it prefers a neutral to acid moist humus-rich soil. It prefers to grow under a light woodland canopy. Plants are hardy at Kew but they grow better in the milder areas of Britain. They rarely exceed 2 metres in height in cultivation and are slow growing. The dormant plant is fairly cold-tolerant, but the young growth in spring is subject to damage by late frosts.
Propagating it: Seed - can be sown as soon as it is ripe in a cold frame. Stored seed may require 2 - 3 months cold stratification and is best sown as soon as possible in a cold frame. Germination takes 2 - 3 months or more at 15°c. When they are large enough to handle, prick the seedlings out into individual pots and grow them on in the greenhouse for at least their first winter. Plant them out into their permanent positions in late spring or early summer, after the last expected frosts. Cuttings of half ripe wood, July/August in a frame. Cuttings of mature wood of the current year's growth in a frame. Layering in September/October of current years growth if possible. If this is not available then use the previous years growth. Takes 18 months. Good percentage.
Best place to grow: Woodland Garden Dappled Shade; Shady Edge;
Habit: Shrub
Hardiness: 7-10
Growth: Slow
Soil: Light (sandy), medium
Shade: Semi-shade
Moisture: Moist