June in the hills with Chris Horne
Leptopteris superba, heruheru, Prince of Wales feathers, crape fern, double crepe ferns
Origin of the names
The Greek word for ‘thin’ is ‘leptos’; the Greek word for ‘fern’ is ‘pteris’; ‘superba’ comes from the Latin word meaning ‘magnificent, exalted’. ‘Heru’ in Te Reo means ‘comb’ - see Uses section below.
Concise Oxford Dictionary: ‘crape’ = crepe; ‘crape fern’ = NZ fern with tall, dark-green plumes; ‘crepe’ = gauze-like fabric with wrinkled surface.
Distribution and habitat
On Te Ika a Māui/North Island, this fern is rare in Northland and Coromandel, and common south of the Bay of Plenty to Wellington. On Te Wai Pounamu/South Island, it is abundant in Westland. It also occurs on Rakiura/Stewart Island. Look for it in cool, wet, dense, montane forests up to 1,000 m elevation, and, rarely, in dwarf form in subalpine scrub, up to 1,350 m elevation.
Leptopteris superba has an erect trunk/rhizome up to 100 cm tall.
The stalks/stipes of the fronds are 1.5-8 cm long, pale brown, with brown, woolly hairs and ear-like lobes at their bases. The dark green, woolly, hairy fronds are 25-100 cm long x 8-25 cm wide, and taper equally towards both ends. There are 35-60 pairs of segments/pinnae crowded along the stem/rachis. The lowest segments are only 0.5-1 cm wide. Their ends, which are linear, stick up at right angles to the plane of the frond, like the pile of a carpet.
The fronds, like those of Leptopteris hymenophylloides, are mostly one cell thick and translucent, just like the fronds of filmy ferns, with which they can be confused when immature. Place your hand under a frond, or the frond of one of the filmy ferns, then move your hand from side to side. Shadow-like, you will see your hand moving on the other side of the frond.
The sporangia, the capsules which contain spores, are scattered on the undersides of the fronds. This is in contrast to the ferns with discretely-grouped sori, as described in articles earlier than May 2017. This distinctive feature of the Leptopteris genus led to it being classified as a member of an ancient family of ferns, the Osmundaceae.
Māori used the hard stipes/stalks of the fronds as teeth for heru/hair combs (Best, 1899, 1908). Māori bruised the fronds to a pulp to make a poultice for bruises. They used the fronds to line hangi/ovens when steaming tawa kernels (Best, 1903).
Leptopteris superba was exported to Victorian England in the 1800s during a ‘fern craze’ there, where it remains popular. Fibre from this fern was once used for orchid-growing, but fibre from sedges and tree ferns is easier to obtain.
Where to look for heruheru/Prince of Wales feathers
Look for this widespread fern whenever you go tramping in cool, wet montane forests up to 1000m elevation, or occasionally higher. Its delicate, filmy-textured, fluffy fronds are a photogenic feature in our forest parks and national parks. In NZ Ferns and Allied Plants, Dr Patrick Brownsey describes this plant as “One of our most beautiful ferns”, rightly called superba.