Family: Salicaceae
Origin, Description & Uses
Xylosma congesta is an evergreen shrub or small tree native to central and southern China, Taiwan, Korea, and Japan. It is valued as an ornamental plant for its dense, glossy green foliage, attractive reddish new growth, and ability to tolerate pruning, making it a popular choice for hedges, screens, windbreaks, and topiary. Adaptable to a variety of growing conditions, it performs well in full sun to partial shade and is widely planted in gardens and landscapes for its year-round appearance and low maintenance requirements.
Risks & Threats
Although Xylosma congesta is not known to be naturalized in Hawaiʻi, it possesses traits that are cause for concern. The species produces abundant fleshy fruits that are readily consumed and dispersed by birds, increasing its potential to spread beyond cultivation. It is also adaptable to a range of environmental conditions and forms dense growth that could compete with other vegetation if it were to escape cultivation. Ongoing evaluation is needed to determine whether this species could become naturalized or negatively impact Hawaiʻi’s native ecosystems. In the meantime, caution is recommended when planting it near natural areas, and gardeners should monitor for unwanted seedlings and prevent fruit from dispersing into surrounding habitats.
High Risk Traits:
- Mostly temperate but can grow in tropical climates
- Broad climate suitability
- Reported to be invading Houstons bayous and creeks
- Branches spiny when young
- Shade-tolerant
- Tolerates many soil types
- Fleshy-fruited berries presumably adapted for dispersal by birds and other frugivorous animals
- Tolerates severe pruning
Low Risk Traits:
- Popular ornamental plant in mainland US with limited reports of escape or invasiveness
- Palatable to browsing animals
- Non-toxic
- Promoted for use in fire resistant landscapes
- Missing information on biology and ecology makes accurate risk prediction difficult
