Hiya distans

Botanical name: Hiya distans
Synonyms: Hypolepis distans
Common name(s): No widely established common name; formerly commonly referred to under Hypolepis distans

About:
A distinctive creeping fern with slender polished red-brown stalks and long, relatively narrow, harsh-textured fronds. Hiya distans spreads through long-creeping underground rhizomes and often forms loose tangled colonies because its slender frond stalks are not always strong enough to hold the fronds completely upright.

It is primarily a fern of damp, peaty and humus-rich habitats and is readily recognised by its widely spaced pinnae, which arise at almost right angles to the main frond axis, and by its dark red-brown stipes.

Formerly known as Hypolepis distans, it is now placed in the genus Hiya.

Natural habitat:
Usually found in swampy or permanently moist environments, especially where soils contain peat or a deep accumulation of organic matter.

It occurs around wetland margins, drainage channels, river terraces, bogs, forest clearings, road banks and disturbed forest margins. It also readily colonises decomposing logs and humus mounds.

In northern New Zealand it may occur beneath kauri forest and mānuka, while further south it is associated with podocarp-broadleaf forest, kānuka, mānuka and occasionally pine plantations.

Growing environment:
Moist Soil, Humus, Peat, Sun & Partial Shade tolerant. Best grown in damp, organic-rich soil with reliable moisture.

Endemic distribution:
Indigenous but not endemic to New Zealand.

Occurs through much of the North Island and more locally in the South Island, particularly Marlborough, north-west Nelson, the Marlborough Sounds, Westland and scattered southern localities. It also occurs on Stewart Island/Rakiura and the Chatham Islands.

Outside New Zealand it is found in parts of Australia, including New South Wales and Tasmania, and is naturalised on Norfolk Island.

Height:
Fronds commonly 30–100 cm long, occasionally considerably longer in favourable conditions.

Width:
Individual fronds may reach approximately 40 cm wide, while creeping rhizomes can spread outward indefinitely and form colonies several metres across.

Flowering:
Not applicable – fern reproducing by spores.

Fruiting:
Not applicable – fern reproducing by spores.

Spores are produced in marginal sori beneath the fronds.

Uses:
• Wetland and bog gardens
• Native fern collections
• Damp woodland planting
• Peaty and humus-rich sites
• Riparian restoration
• Naturalistic forest gardens
• Shaded or semi-open banks
• Restoration of disturbed wetland margins
• Botanical and educational collections

Appearance:
Growth habit:
A terrestrial fern spreading through slender, long-creeping underground rhizomes approximately 1–2.5 mm in diameter.

Fronds arise individually along the rhizome at intervals, rather than from a compact crown.

The frond stalks are comparatively weak, meaning mature fronds commonly lean, scramble across the substrate or intertwine with surrounding vegetation, eventually producing loose mounds of foliage.

Leaves:
Fronds are narrowly elliptic, elliptic or sometimes ovate and are relatively stiff and harsh to the touch.

They are generally twice pinnate and deeply divided, with particularly large specimens approaching three-pinnate division toward the base.

Primary pinnae occur in approximately 15–40 pairs and are conspicuously widely spaced. They arise almost at right angles to the rachis, giving the frond a distinctive open appearance.

Secondary pinnae are ovate to narrowly ovate and deeply serrated or divided. Unlike many related ferns, those toward the lower portions of a primary pinna remain fairly similar in size and only gradually decrease toward the tip.

Fronds:
The stipe is slender, polished and characteristically dark red-brown, usually with only a few scattered hairs.

The rachis remains red-brown for most of its length and becomes paler only toward the tip.

The upper surface of the frond is almost hairless, while the underside carries only sparse pale brown hairs along the main veins and midribs.

This sparse hair covering contributes to the clean, rather rigid appearance of the species.

Spores:
Sori occur close to the margins of the smallest frond divisions, usually in several pairs.

Each sorus develops at the end of a vein and is protected by a reflexed, finely toothed flap of the frond margin.

Mature spores are dark brown and are dispersed by wind.

Ecology:
Hiya distans is particularly adapted to damp, organic substrates.

Its creeping rhizome allows it to expand through peat, humus and decomposing woody material, while new fronds can arise some distance from the original plant.

It is commonly associated with wetlands but also occupies forest margins, disturbed soil and decaying logs where moisture remains consistently available.

The weak frond stalks often result in plants scrambling through neighbouring vegetation rather than forming an upright fern crown.

Wind-dispersed spores enable the species to colonise new disturbed or wet habitats, and it may occasionally appear unexpectedly in nurseries where peat-containing potting material has introduced spores or rhizome fragments.

Associated habitats:
Peat bogs, swamp margins, wetland edges, Carex-dominated wetlands, drainage ditches, river terraces, forest clearings, decomposing logs, humus mounds, forest margins, road banks, mānuka and kānuka scrub, podocarp-broadleaf forest and occasionally pine plantations.

How to grow:
A relatively easy fern to cultivate where moisture is reliable.

Plant in humus-rich, peaty soil that remains consistently damp. Peat-like organic substrates closely resemble many of its natural growing conditions.

It grows well in sun where the soil remains moist, but also tolerates partial shade and woodland conditions.

Once established it can tolerate a reasonably broad range of moisture levels, although prolonged drying should be avoided.

Allow room for its creeping rhizomes and naturally sprawling fronds.

Propagation:
Easily propagated from fresh spores or by division of established plants.

For division, lift a section of creeping rhizome carrying healthy roots and one or more developing fronds. Replant into damp, organic-rich soil and maintain consistent moisture until established.

Spores can be sown onto a sterile, moisture-retentive propagation medium and kept warm, humid and shaded from intense sunlight.

Cultural use:
No specific traditional Māori use is widely documented for Hiya distans.

Its significance lies primarily in its role as part of New Zealand’s indigenous wetland and forest-margin fern flora.

Garden value:
A useful fern for damp, naturalistic gardens where its unusual open frond structure can be appreciated.

The polished red-brown stipes, widely spaced pinnae and sprawling growth give it a character quite different from more conventional upright native ferns.

It is especially suitable for bog gardens, wet woodland margins, damp banks and peat-rich native plantings, where its creeping habit allows it to gradually form loose colonies.