Included here are the Kermadecs a group of subtropical volcanic islands situated close to the Kermadec Trench in the South Pacific. The most important are Macauley Island, Curtis Island and Sunday Island but Sunday is by far the largest reaching an elevation of some 300 m.

These forests can be divided into two types, broadly classified as wet hill forest (above an altitude of about 200 m) and dry lowland forest. Amongst the dominant trees of the lowland forest are the endemic Coprosia acutifolia (Rubiaceae), Homolanthus polyandrous (Euphorbiaceae), Metrosideros kermadecensis (Myrtaceae), Rapanea kermadecensis (family?) and the endemic tree fern Cyathea milnei (Cyatheaceae). Several of these are adapted to seasonal dryness - Homolanthus polyandrus is semi-deciduous, while others such as Rapanea kermadecensis are able to roll their leaves. Although less conspicuous than in the wet forests, the epiphytes may include Asplenium caudatum and Nephrolepis cordifolia, while the forest floor tends to be dominated by tree seedlings with species such as Corynocarpus laevigata and Rapanea kermadecensis often forming dense patches.  In the wet forest the endemic trees include Ascarina lanceolata (Chloranthaceae), Neopanax kermadecense (Araliaceae) and the palm Rhopalostylis cheesemanii (Arecaceae) together with endemic tree fern Cyathea kermadecensis (Cyatheaceae). Other less common trees include the endemic Boehmeria dealbata (Urticaceae). Amongst the luxuriant cover of epiphytes is the ancient psilopsid Tmesipteris tannensis, ferns such as Asplenium flaccidum, Hymenophyllum demissum, Cyclophorus serpens, clubmosses such as Lycopodium billardieii and flowering plants such as Peperomia endlicheri. The forest floor is also richly covered in lower plants with many mosses and ferns such as Blechnum norfolkianum and Drypteris glabella.

References

Balgooy, Van. M. M. J. 1960. Preliminary plant geographical analysis of the Pacific. Blumea, 10: 385-430.

Balgooy, Van. M. M. J. 1969. A study of the diversity of island floras. Blumea, 17: 139-178.

Molloy, L. 1994. Wild New Zealand. The MIT Press, Cambridge, Massachusetts.

Mueller-Dombois, D. & Fosberg, F. R. 1998. Vegetation of the Tropical Pacific Islands. Springer.

Oliver, R. B. 1910. The vegetation of the Kermadec Islands. Transactions and Proceedings of the New Zealand Institute, 42: 118-175.

Sykes, W. R. & West, C. J. 1996. New records and other information on the vascular flora of the Kermadec Islands. New Zealand Journal of Botany, 34: 447-462.

Wace, N. M. 1960. The botany of southern oceanic islands. The Royal Society Expedition to Southern Chile. Proceedings of the Royal Society, 152: 475-490.