Family: Marattiaceae
A. evecta, commonly known as mule’s foot fern, was imported to Hawaiʻi in 1927 by H.L. Lyon for what would become the Lyon Arboretum. Native to Polynesia, Melanesia, Micronesia, Australia, and New Guinea. It quickly escaped cultivation and became a pest within the arboretum and continued to spread into Manoa valley and beyond. Meanwhile, other populations established on the borders of botanical gardens around the state. Documented as naturalized in 1950, mule’s foot fern has escaped cultivation on all the main Hawaiian Islands.
Mule’s foot fern is invasive in Costa Rica and Jamaica. This fern should not be cultivated. The Division of Forestry and Wildlife of the Hawaiʻi Department of Land and Natural Resources has designated this species as one of Hawaiʻi’s Most Invasive Horticultural Plants.
Description and Dispersal:
- Massive terrestrial fern
- Huge 2-pinnate fronds up to 7 x 3 m (23 x 10 ft)
- Fronds arising from short, thick trunks
- 2 large, fleshy appendages (stipules) at the swollen base (pulvinus) of each stipe
- Pinna stalks with swollen bases (pulvini) and special spore-bearing structures on the undersides of the pinnules
- Numerous spores are wind dispersed
High Risk Traits:
- High climate match for tropics/subtropics
- History of introductions outside native range
- Naturalized in multiple regions (e.g., Hawaii, Jamaica)
- Environmental weed – crowds out native species
- Shade tolerant
- Forms dense thickets
- Produces viable spores in large quantities
- Reproduces vegetatively from fragments
- Wind and water-dispersed spores
- Prolific spore production
- Lacks effective natural enemies in invaded areas
Low Risk Traits:
- Narrow climate suitability (only wet tropics/subtropics)
- No spines, toxicity, or allelopathy
- Palatable to grazers (e.g., goats)
- Not a fire hazard
- Limited soil tolerance
- Slow maturation (years to reproduce)
- Not dispersed by animals
- Sensitive to fire and physical damage
