Hairy Fern
Botanical name: Lastreopsis hispida
Synonyms: Rumohra hispida, Polystichum schkuhrii, Nephrodium hispidum, Polypodium setosum, Polystichum hispidum, Aspidium hispidum, Dryopteris hispida, Lastrea hispida
Common name(s): Hairy fern
About:
Lastreopsis hispida is a distinctive indigenous fern recognised by its harsh, finely divided brownish-green fronds and the conspicuous dark bristle-like scales covering its stalks, central axes and veins. These coarse scales give the fern its characteristic rough, hairy appearance and are reflected in the specific name hispida, meaning roughly or bristly hairy.
It is predominantly a terrestrial forest fern, spreading through creeping rhizomes to form loose colonies on moist forest floors, banks, gullies and stream margins. Although most often encountered at ground level, it occasionally establishes on fallen logs or as a low epiphyte on tree ferns.
Unlike several New Zealand species formerly included in Lastreopsis that have subsequently been transferred to Parapolystichum, L. hispida remains within Lastreopsis.
Natural habitat:
Coastal to montane forest from near sea level to approximately 915 m elevation.
It occurs in kauri, podocarp, broadleaved, beech and coastal forest, as well as beneath kānuka.
Typical sites include moist forest floors, hillsides, clay banks, streambanks, river terraces, rocky gullies, track margins, amongst boulders and on decaying logs.
It occurs on a variety of geological substrates, including greywacke and limestone, but is particularly characteristic of shaded, humid forest environments.
Growing environment:
Shade, Partial Shade, Moist Soil, Humus-rich Soil & Sheltered conditions tolerant.
Hairy fern performs best in permanently moist but well-drained soil with abundant organic matter and protection from excessive drying.
It is well adapted to the filtered light and high humidity of forest interiors and sheltered gullies.
Endemic distribution:
Indigenous to New Zealand but not endemic.
In New Zealand it occurs throughout much of the North Island from Te Paki south to Wellington, although it is largely absent from the central high country.
In the South Island it is principally a coastal and lowland species, extending from the Marlborough Sounds and north-west Nelson through western districts to Fiordland and Southland. Eastern populations are more localised, including Banks Peninsula, Dunedin and the Catlins.
Also present on Stewart Island/Rakiura and the Chatham Islands.
Outside New Zealand it occurs naturally in south-eastern Australia, including New South Wales, Victoria and Tasmania.
Height:
Fronds approximately 26–140 cm long, although plants are commonly considerably smaller.
Width:
Variable according to age and rhizome spread. Individual fronds may reach approximately 40–55 cm wide, while established creeping plants can gradually form broader colonies.
Flowering:
Not applicable. As a fern, Lastreopsis hispida does not produce flowers.
Fruiting:
Not applicable. Reproduction is by spores rather than fruits and seeds.
Fertile fronds bear numerous round sori on their undersides.
Uses:
• Shaded native gardens
• Fern gardens and ferneries
• Forest restoration
• Streamside and riparian planting
• Shaded banks and gullies
• Underplanting beneath native trees
• Woodland groundcover
• Specialist native fern collections
• Naturalistic gardens
• Humid courtyard and sheltered garden planting
Appearance:
Growth habit:
A terrestrial, creeping perennial fern producing crowded fronds from a horizontally spreading rhizome.
The finely divided fronds form an attractive arching mass of dark brownish-green foliage. Their texture is noticeably harsher than that of many superficially similar forest ferns.
Plants usually grow terrestrially but may occasionally occur on rotten or fallen logs or as low epiphytes.
Rhizomes/Stems:
Rhizomes are creeping, approximately 4–10 mm in diameter, and densely clothed in persistent dark reddish-brown to almost black scales.
Rhizome scales are narrow and bristle-like, approximately 4.5–17 mm long.
The stipes are approximately 12–87 cm long, reddish-brown toward the base and becoming paler farther up. They are densely covered with conspicuous stiff, dark bristle-like scales and numerous much smaller glandular hairs.
The rachis is similarly clothed in dark scales and hairs, making this combination one of the species’ most useful identification features.
Leaves:
The frond blade is broadly ovate to somewhat triangular in overall outline and usually divided three or four times, occasionally five times.
Laminae measure approximately 14.5–63 cm long and 8–40 cm wide, exceptionally reaching around 55 cm wide.
The foliage is brownish-green on both surfaces and has a distinctly harsh or rough texture.
Primary pinnae occur in approximately 12–21 pairs below the divided apex. The lower pinnae are usually the longest, giving the blade its broad basal outline.
Successive divisions become progressively narrower, with the ultimate segments narrowly ovate to oblong-lanceolate, sharply pointed and deeply serrated. Their margins are often cut into conspicuous narrow, curved teeth.
Dark bristle-like scales occur along the veins and midribs, accompanied by smaller brown hairs and minute glandular structures.
Flowers:
Absent.
Ferns do not produce flowers. The reproductive structures are sporangia grouped together into sori on the undersides of fertile fronds.
Fruit:
Absent.
No fruit or capsules are produced.
Seeds:
Absent.
Reproduction is by microscopic spores produced within sporangia.
The sporangia are grouped into rounded sori positioned along the veinlets, generally closer to the frond margin than to the central costa. Each sorus is protected while developing by a pale brown, kidney-shaped indusium approximately 0.6–0.8 mm across.
Ecology:
Lastreopsis hispida contributes to the dense ground layer of moist New Zealand forests, particularly in lowland and riparian environments.
Its creeping rhizomes allow established plants to gradually occupy suitable patches of forest floor, while the finely divided fronds contribute shelter and structural complexity for small forest invertebrates.
It frequently occupies humid microsites such as streambanks, gullies, shaded slopes and decomposing woody material where moisture remains relatively reliable.
Although principally terrestrial, its occasional occurrence on fallen trees and as a low epiphyte demonstrates its ability to exploit deep accumulations of moist organic material above ground level. It has been recorded growing on tree ferns including Cyathea dealbata and Cyathea smithii.
Associated habitats:
Kauri forest, podocarp forest, broadleaved forest, beech forest, coastal forest, kānuka woodland, riparian forest, stream margins, rocky gullies, shaded clay banks, river terraces and moist forest floors.
It may grow amongst tree ferns, mosses, liverworts and numerous other indigenous forest-floor ferns and herbs.
How to grow:
Hairy fern is readily cultivated when provided with conditions resembling a moist forest floor.
Plant in partial to full shade in deep, humus-rich soil that remains consistently moist while still draining freely.
Incorporating leaf mould, composted bark or other well-decomposed organic material helps reproduce the loose forest litter in which the species naturally thrives.
Shelter plants from hot afternoon sun and drying winds. Once established, the creeping rhizomes can gradually spread and produce additional fronds.
It is particularly effective beneath native trees, beside shaded streams or ponds, on sheltered banks and in dedicated fern gardens.
Propagation:
Propagation is possible from spores or by careful division of established rhizomes.
For vegetative propagation, sections of healthy creeping rhizome carrying established roots and growing points can be carefully separated and replanted into moist, humus-rich media.
Keep divisions shaded and consistently moist while they re-establish.
Spore propagation is slower and requires clean, humid conditions. Mature fertile fronds can be collected when the sori are developed and the spores sown onto a sterile, moist propagation medium. Developing gametophytes must be maintained under humid conditions until young sporophytes form.
Cultural use:
No specific traditional Māori material use is well documented for Lastreopsis hispida.
Its importance lies primarily in its role as part of the diverse fern flora characteristic of Aotearoa’s indigenous forests.
Garden value:
An excellent fern for creating an authentic New Zealand forest-floor character in shaded gardens.
Its broad, intricately divided brownish-green fronds have a strong textural quality, while the conspicuous dark bristles along the stalks and frond axes provide additional botanical interest when viewed closely.
Hairy fern is especially suited to moist woodland gardens, shaded banks, ferneries and riparian plantings where its creeping habit can gradually produce natural-looking colonies beneath taller native vegetation.