Australian Tree Fern
Australian tree fern (Cyathea cooperi)
Hawaii Pacific Weed Risk Assessment: 16, High Risk
Regulatory Status: None
Prevention and Control Category: MoMISC Target Species
Report this species if seen on Molokai
Description
- Large tree fern up to 12 m (40ft) tall with large (up to 6m long) triangular leaves, lacy blades
- Scaly, brown stems fall off when dead, leaving oval scars
- White hairs on stalks (unlike native hapuu, which has red hairs)
- Trunk doesn’t have the thick, soft fiber wrapping like the native hapuu
- Native to Australia, introduced to Hawaii as an ornamental
Impacts
- Wind spread spores can travel over 12 km (7 miles) from parent plant, as seen when plants from Hana nurseries spread to Kipahulu Valley.
- Fast growing and aggressively outcompetes native plants in the forest understory
- Displaces native ferns, including the slower growing hapuu
Distribution
- Kauai: Spreading in native forests including Hanalei, Koloa, and Kokee. Landowners are asked to plant non-invasive alternates instead.
- Oahu: Spreading in the Koolau and Waianae mountains. Landowners are asked to plant non-invasive alternates instead.
- Maui: Widely cultivated and naturalized. Infesting Kipahulu Valley, Peahi, Haiku, and areas in West Maui.
- Molokai: No infestations known in the wild, although planted in landscaped areas at several residences. MoMISC is working to educate community members to remove these plants and select non-invasive alternates.
- Lanai: Presence/absence unknown
- Kahoolawe: None known.
- Big Island: Spreading from landscaped areas in Volcano, Laupahoehoe, Kona and other areas. Landowners are asked to plant non-invasive alternatives instead of non-native tree ferns.