homebanner homebanner homebanner homebanner homebanner homebanner
Distylium racemosum - Siebold.&Zucc.
Common Name Isu Tree
Family Hamamelidaceae
USDA hardiness 7-10
Known Hazards None known
Habitats Evergreen oak forests. Forests at elevations of 1000 - 1300 metres in Fujian, Hainan, Taiwan and Zhejiang Provinces of China[266].
Range E. Asia - China, Japan.
Edibility Rating  
Other Uses  
Weed Potential No
Medicinal Rating  
Frost Hardy Moist Soil Semi-shade


Distylium racemosum Isu Tree

Distylium racemosum Isu Tree
Physical Characteristics
 icon of manicon of shrub
Distylium racemosum is an evergreen Shrub growing to 2 m (6ft) by 3 m (9ft) at a slow rate.
It is hardy to zone (UK) 8 and is frost tender. It is in leaf 12-Jan It is in flower from Mar to April, and the seeds ripen from Jun to August. The flowers are hermaphrodite (have both male and female organs)Suitable for: light (sandy) and medium (loamy) soils and prefers well-drained soil. Suitable pH: acid, neutral and basic (alkaline) soils. It can grow in semi-shade (light woodland). It prefers moist soil.


Woodland Garden Dappled Shade; Shady Edge;
Edible Uses
None known
Medicinal Uses
Plants For A Future can not take any responsibility for any adverse effects from the use of plants. Always seek advice from a professional before using a plant medicinally.

None known
Other Uses
Porcelain;  Wood.

The ashes of the wood are used in glazing porcelain[46, 61]. Wood - hard, fine-grained, dark brown. A very valuable wood, it is used for small articles, musical instruments etc[11, 46, 61].
Cultivation details
Prefers a sandy soil[1]. A lime tolerant plant, but it prefers a neutral to acid moist humus-rich soil[130, 182]. It prefers to grow under a light woodland canopy[130, 200]. Plants are hardy at Kew[11] but they grow better in the milder areas of Britain[1]. They rarely exceed 2 metres in height in cultivation and are slow growing[11]. The dormant plant is fairly cold-tolerant, but the young growth in spring is subject to damage by late frosts[130].
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[175]. Germination takes 2 - 3 months or more at 15°c[175]. 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[130]. Cuttings of mature wood of the current year's growth in a frame[113]. 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[78].
Other Names
Found In
Weed Potential

Right plant wrong place. We are currently updating this section. Please note that a plant may be invasive in one area but may not in your area so it’s worth checking.

Conservation Status
IUCN Red List of Threatened Plants Status :
Related Plants


Print Friendly and PDF
Expert comment
Botanical References
Links / References
For a list of references used on this page please go here
Readers comment
QR Code

What's this?

This is a QR code (short for Quick Response) which gives fast-track access to our website pages. QR Codes are barcodes that can be read by mobile phone (smartphone) cameras. This QR Code is unique to this page. All plant pages have their own unique code. For more information about QR Codes click here.

1. Copy and print the QR code to a plant label, poster, book, website, magazines, newspaper etc and even t-shirts.
2. Smartphone users scan the QR Code which automatically takes them to the webpage the QR Code came from.
3. Smartphone users quickly have information on a plant directly for the pfaf.org website on their phone.
Add a comment

If you have important information about this plant that may help other users please add a comment or link below. Only comments or links that are felt to be directly relevant to a plant will be included. If you think a comment/link or information contained on this page is inaccurate or misleading we would welcome your feedback at admin@pfaf.org. If you have questions about a plant please use the Forum on this website as we do not have the resources to answer questions ourselves.

* Please note: the comments by website users are not necessarily those held by PFAF and may give misleading or inaccurate information.

To leave a comment please Register or login here All comments need to be approved so will not appear immediately.

Subject : Distylium racemosum  

Plant Uses

Edible Uses
Medicinal Uses
Other Plant uses
Woodland Gardening
Why Perennial Plants?
Top Edible Plants
Top Medicinal Plants
Garden Design

Twiter      Facebook


Content Help
Support Us
Old Database Search
About Us
Sign In

PFAF Newsletter

Stay informed about PFAFs progress,
challenges and hopes by signing up for
our free email ePost. You will receive
a range of benefits including:
* Important announcements and news
* Exclusive content not on the website
* Updates on new information &
functionality of the website & database

We will not sell or share your email address.
You can unsubscribe at anytime.