Family: Athyriaceae
Deparia petersenii (Japanese lady fern, Petersen’s lady fern) is a fern native to tropical and subtropical regions of eastern Asia. It is an ornamental fern sometimes used in shady or wet gardens. It is reported to be naturalized in the southern United States, New Zealand, Australia, and South America. It has also naturalized on the islands of Oʻahu, Lanaʻi, Molokai, Maui, Kauaʻi and Hawaii. This plant poses a threat to endangered Hawaiian plants due to its ability to create a thick ground cover on the forest floor, outcompeting other understory plants. It reproduces vegetatively (by rhizomes) and by prolific spore production, allowing it to spread rapidly and silently. Its spores may be dispersed by wind, water, in potted plants, and accidentally by people.
High Risk Traits:
- Elevation range exceeds 1000 m, demonstrating environmental versatility
- Thrives in tropical climates
- Naturalized on main Hawaiian Islands, and elsewhere
- A weedy fern reported to threaten endangered plants in Hawaii and Reunion Island
- Shade-tolerant
- Tolerates many soil types
- May form dense ground cover that can exclude or compete with rare native plants in the Hawaiian Islands
- Reproduces by prolific spore production, and vegetatively by creeping rhizomes
- Spores dispersed by wind, water, as a pot contaminant, and intentionally and accidentally by people
Low Risk Traits:
- Unarmed (no spines, thorns, or burrs)
- Non-toxic
- Reported to be edible to people
