Family: Dennstaedtiaceae
Hypolepis dicksonioides (giant hypolepis, ground fern) is a fern native to New Zealand, Chatham Islands, Kermadec Islands, Norfolk Island, and The Marquesas. It has been recorded as a weed in garden centers. As such this species has also appeared in urban situations and can be found growing in cities on rock walls, in bark gardens, or even protruding from cracks in asphalt pavements. It is reported to be naturalized in South Australia. It is present in Hawai’i Volcanoes National Park, and perhaps elsewhere on Hawai’i Island. This plant is high risk as it reproduces by prolific spore production and vegetatively by rhizomes. It also can hybridize with other Hypolepis species and runs the risk of potentially crossing with native Hawaiian fern (Hypolepis hawaiiensis).
High Risk Traits:
- Broad climate suitability (temperate to tropical regions)
- Escaped or naturalized in Australia, and the Hawaiian Islands (recently confirmed)
- A short-lived, weedy fern of disturbed habitats, open sites, gardens, and urban environments
- Mistakenly identified as a native fern (Hypolepis hawaiiensis); may be having detrimental effects in the natural environment. Further determination of its current distribution is required.
- Other species are weedy
- Reported to be a short-lived, ephemeral fern in most areas, but capable of forming dense stands on Macauley Island (southern Kermadec Islands)
- Reproduces by spores and vegetatively by rhizomes
- Hybridizes with other Hypolepis species; could potentially cross with native Hawaiian fern (Hypolepis hawaiiensis)
- Spores dispersed by wind, water, as a garden contaminant, and intentionally cultivated in some areas
- Prolific spore production
Low Risk Traits:
- A short-lived fern in much of its natural range; distribution and negative impacts in the Hawaiian Islands currently unknown
- Unarmed (no spines, thorns, or burrs)
- Non-toxic
- Grows best in high light environments (dense shade may inhibit spread)
