Oriental bittersweet
Celastrus orbiculatus
Overview
Habitat
- Found natively on lowland slopes, in thickets, as a hedge plant and under the canopy of low-light forests
- In introduced areas it is found growing on roadsides, fence-rows, hedgerows, saltmarshes, coastal areas and the edges of fields and forests
- Utilises trees, shrubs and scaffolding to climb upwards
Description
- A deciduous, woody, twining vine, which sometimes occurs as a trailing shrub
- Stems are brown in colour, and older stems can reach 10cm in diameter
- Glossy, rounded, finely toothed leaves are arranged alternately along the stem
- Leaves vary in size from 2-12cm long
- Small greenish-yellow flowers grow from the leaf axils, with 5 petals and 5 sepals
- Fruits are 1cm wide, globular and green in colour, turning bright yellow as they mature
- Fruits split when mature to reveal a red aril (seed covering)
- The outer surface of the plant roots is bright orange
Origin and Worldwide Distribution
- Native to China, Japan, Korea, Mongolia and Russia
- It is now widely spread across North America and New Zealand
- It has been introduced in localized areas across Europe, including one occurrence in England
Potential or Known Impacts
- Suppression and exclusion of native species as result of competition
- They choke and shade the plants they climb on, sometimes killing them
- They can weaken the roots of host trees, leading to collapse
Is it found in Northern Ireland?
- It is not currently present in Northern Ireland
How could it get here?
- Introduction would likely be a result of the accidental or deliberate spread of individuals grown in gardens as ornamental vines
- Dumped seeds and pieces of root moved in soil e.g. to landfill can also cause spread
- Once present, spread can continue by dispersal of fruits via birds and other wildlife
Management/Methods for Prevention
- Prevention via enforcing the IAS (Enforcement and Permitting) Order (Northern Ireland) ensuring that C. orbiculatus is not introduced to Northern Ireland
- Reporting all sightings so that Rapid Response can be instigated
- If Rapid Response is not successful, management can include physical and chemical control
Current Legislative Position (Entry into force: 02 August 2027)
- This species must not intentionally be brought into the Union; kept; bred; transported to, from or within the United Kingdom, unless for the transportation to facilities in the context of eradication; placed on the market; used or exchanged; permitted to reproduce, grown or cultivated; or released into the environment.