The fern names palatao (Niuean) and paretao (Māori) are possibly reflexes of a Proto Polynesian word, either *paletao or palatao (possibly both, as variant forms with a common meaning), although on the surface the ferns they refer to appear to have little in common besides their shiny leaves, and perhaps the shape of the leaflets on the fronds. The Niuean pair are species of giant ferns native to parts of Pacific, but which can be highly invasive.in new environments. Angiopteris evecta has fronds up to 7 metres long. It is a native of the Western Pacific, including Western Polynesia; it was introduced to Hawaii in the 1920s and has become a serious threat to native flora in some forests to which it has escaped. Pteris tripartita is another widely distributed giant fern, a little smaller than the Angiopteris (fronds up to 3 metres long), but has also become a menace outside its native habitats.
Asplenium oblongifolium
 Asplenium oblongifolium (formerly A. lucidum) and A. obtusatum are comparatively smaller ferns than their tropical namesakes, but can form a conspicuous part of the environments in which they thrive. The glossy, dark green fronds of A. oblongifolium (pictured on the left) can reach about a metre and a half in length when it is growng in optimum conditions in open but shaded parts and moist parts of the forest with soils rich in humus. It will also grow on rocky banks, rotten logs, tree stumps, as an epiphyte on the trunks of tree ferns or the forks of forest trees, and in deep shade or open sunny positions. In drier, more exposed conditions it will hold its own but may adopt a much more compact form than in the moister, more sheltered habitats. In some environments it will form a dominant feature of the the forest understory, which may be what originally merited its heritage name. It is found most often near the coast, throughout the North Island, and from Hokitika and Banks Peninsula north in the South Island.
This species is endemic to New Zealand and the Kermadecs. Although it is easy to cultivate and will grow in a wide range of conditions, its leaves seem to be very attractive to rabbits, which can munch through an entire plant in an evening. It is known to hybridize with several other species of Asplenium, particularly A. bulbiferum and the rather similar A obtusatum. Asplenium oblongoifolium is also known as uruuruwhenua, possibly because it can be the dominant groundcover in parts of the forest or hillside bush.
Asplenium oblongifolium had dual uses as a vegetable (the young shoots of this species and the mauku (A. bulbiferum) were eaten as a salad greens) and as a sacred plant used in important ceremonies. The frond was a medium of divination, both in preparing for military and other enterprises, and in assessing the progress of an illness. Should the fern break in ceremonies before a battle or other planned enterprise, or in treating an illness, it was a sign that the affair was ill-fated and should be abandoned, or the outlook for the patient's recovery was not good. If it remained unbroken, the good health of the patient or success of the undertaking was highly likely to ensue.
Asplenium obtusatum
A. obtusatum is a coastal fern, about half the size of A. oblongifolium, with much duller and thicker foliage; it grows naturally mainly in exposed places, often perched on rocks or among coastal herbage exposed to sea spray. It is also found in South America, sub-antarctic islands, Australia and some Pacific Islands. Both ferns have as alternative names paranako or parenako (again probably partly reflecting Proto Polynesian *para). Partly because of the number of intermediate forms between them, and the characteristics assumed by A. obtusatum when growing in some coastal environments (e.g. duller, more fleshy and stubbier fronds), the late A.H. Dobbie thought that A. obtusatum may turn out to be simply a habitat form of A. oblongifolium (New Zealand Ferns, p. 329). However their separate botanical taxonomic status has so far been retained.
Angiopteris evecta
 Angiopteris evecta is a truly large fern; its short trunk can be 50 cm or more in diameter, and the fronds 7 metres long and 3 metres wide, with lustrous, dark-green leathery leaves (although they may be lighter in colour on the newly unfurling fronds, like those pictured on the left). These gigantic fronds are held up by hydraulic pressure rather than woody fibres strengthening the stem. The fern is native to Southeast Asia from Srilanka and Bangladesh east, and much of Oceania, including Northeastern Australia, along with Japan. It was probably once even more widely distributed as there are traces of a very similar species in the fossil record from every continent and the species seems to have been around for at least 300 million years.The root is edible, but probably it is more a famine food than a staple in most places where it grows as it requires careful processing to remove toxins. This fern can be highly invasive outside its native range, as it is in Hawai'i, where it was introduced at the Lyon Arboretum and then escaped to invade parts of the Mānoa Valley and the mountains behind Honolulu. It is also a problem on the island of Maui. On the other hand, it is an endangered species in some of its Australian and other native habitats.
Pteris tripartita
Pteris tripartita is native to tropical Asia and the Pacific; it has also been introduced into the Americas where it has become invasive in wetlands. Like the Angiopteris, it is not troublesome in its native habitats: one of the photos in the gallery was taken on an organic farm in the Philippines where it is probably an isolated remnant of the vegetation which once covered the area where it is growing. Each plant can grow up to 2 m tall, with the blades of its fronds up to one and a half metres long and broad. There are only a few fronds per plant. In Tahiti it is known as fare rupe ("pigeon house") -- 'are rupe in Rarotonga -- apparently because the fronds were once used as camoflage by pigeon hunters. It prefers swampy ground, but is also found in disturbed ground and also in forest and other areas where the ground is consistently moist.
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