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Bog Forest

Bog Forest is dominated by Dracophyllum arboreum and was once very extensive. It is now largely restricted to the southern tableland. The Dracophyllum has quite broad leaves when young, but the adult leaves are needle-like. This species often begins life as an epiphyte on a tree fern and eventually becomes free standing on its own coalesced roots. Of Dracophyllum arboreum Wright¹⁶⁸ says: 'In many respects a parallel can be drawn between the kauri tree (Agathis australis) of Northland … and Dracophyllum arboreum in the Chathams. Both trees accumulate a large mound of organic residues, both condition strongly the soil leaching processes and bring about podsolisation, and both become the dominant species when the soils are sufficiently conditioned. The litter in the case of each species consists of leaf, twig and bark residues of high resinous composition.' The tree ferns Dicksonia squarrosa and D. fibrosa are prominent in the understory and filmy ferns on the forest floor and, as epiphytes, are a prominent feature.