Family: Aspleniaceae
Origin, Description & Uses
Woodwardia radicans, commonly known as chain fern or rooting chainfern, is a large, evergreen fern native to Macaronesia and the Mediterranean region. It thrives in moist, shaded forests, streambanks, and other humid habitats, where its gracefully arching fronds can reach several feet in length. A distinctive feature of this species is its ability to produce small plantlets along the tips of its fronds that root when they touch the ground, forming new plants. Because of its lush, tropical appearance and tolerance of shade, chain fern is widely grown as an ornamental in woodland gardens, shaded landscapes, botanical collections, and water gardens.
Risks & Threats
Although Woodwardia radicans is not currently known to be naturalized in the Hawaiian Islands, it possesses traits that warrant caution. Its ability to reproduce vegetatively through rooting frond tips, combined with spore production and its preference for moist, shaded environments, could allow it to spread beyond cultivation if introduced into suitable habitats. In tropical island ecosystems, these characteristics could enable it to establish dense colonies that compete with native ferns and understory vegetation, particularly in wet forests and riparian areas. To help protect Hawaiʻi’s unique ecosystems, it is recommended that gardeners and landscapers choose low-risk or native fern species whenever suitable alternatives are available.
High Risk Traits:
- Able to grow in temperate to subtropical climates
- Naturalized in the British Isles and Florida,
- Shade-tolerant
- Forms dense stands in native range
- Reproduces by spores and vegetatively by adventitious bulbils
- Spores dispersed by wind and water
- Intentionally propagated
- Presumably prolific spore production
- Possibly bird-dispersed in Azores
Low Risk Traits:
- Despite naturalization, no negative impacts documented
- Cultivated, but not reported as naturalized, in Hawaiian Islands
- Unarmed (no spines, thorns or burrs)
- Ornamental
