Pakihi are a type of wet heath, characterised by very infertile soils with an impervious horizon and little or no peat. In South Westland, pakihi have developed as a result of natural processes of inundation of soils where there is impeded drainage combined with soils becoming very infertile as a consequence of developing in areas of very high rainfall. These soils are too infertile to support closed forest. Pakihi-type vegetation, as occurs in northern Westland, has been induced by human fire. Pakihi share both environmental and vegetation features with North Island gumlands. Characteristic species are manuka (Leptospermum scoparium), wire rush (Empodisma minus), Centrolepis pallida and tangle fern (Gleichenia dicarpa).
Where do they occur?
Pakihi are confined to the west of the South Island where they are widely scattered, particularly on old outwash gravels.
Notable flora and fauna
Threat statusNot threatened (Holdaway et al. 2012)
Weed invasion primarily occurs on the margins, e.g. gorse (Ulex europaeusi), pasture weeds and grasses, and there may be some damage on the margins in agricultural settings. Pakihi may be threatened by peat mining and by coal mining when they occur over coal measures. They are subject to burning, especially in dry seasons when there has been a build up of fuel. They have often been burned by hunters, who are probably the most frequent human visitors.
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