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Emerging fern fronds, such a distinct image of Aotearoa/ New Zealand. This shape is known as a koru in Maori. The koru, represents the unfolding of new life, that everything is reborn and continues.
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GEOLOGY, FLORA & FAUNA
The flora on Mt. Aorangi changes from a podocarp based forest at lower altitudes, through to Beech forest, and then into sub alpine plant species on the summit.
Since a possum control program was carried out over the last several years, there has been a heartening return of some plant species that were becoming increasingly rare. One of the more unusual and striking of these is the Red mistletoe / Pirirangi, Peraxilla tetrapetala. New Zealand’s endemic mistletoes provide some of the brightest flowering displays in our native bush, but seem to be retreating under the impact of possum browsing. Recent discoveries on the pollination of these plants have revealed a unique dependence on native birds which may also pose problems for their conservation.
To overseas botanists, the flowers of New Zealand’s native plants often seem drab: many are small, white and inconspicuous. Among the most wonderful exceptions to this rule are the three surviving native bird - pollinated mistletoes. Both species of Peraxilla - P. colensoi and P. tetrapetala - have masses of bright red flowers each up to 5 cm long, while the closely related Alepis flavida has smaller but still attractive yellow-orange flowers.
These plants grow on host beech trees (which don’t seem to be harmed even by high densities of mistletoes) and provide one of the few sources of colour, nectar and fleshy fruits in beech forests. However, all native mistletoes seem to be decreasing in abundance in a pattern which has been linked to spread of possums, and in most of the North Island it is now rare to see a mistletoe.
Some text above comes from:
Forest & Bird Magazine No 278, Nov 1995 P 16
By Jenny Ladley and Dave Kelly Recent work on the pollination of bee species, however, has revealed some complex and wonderful systems of dependence. Unfortunately these interactions shows that mistletoes are vulnerable not just to possum browsing, but also indirectly to decline in the populations in native honey eaters (Tui and Bellbirds).
In both Peraxilla species, flower buds are unable to open themselves. The flowers reveal themselves only when the honeyeater finds a ripe bud and gives the top a twist; the bud then bursts open immediately like a spring, and the bird drinks the nectar inside. The whole process takes less than a second per flower. Birds can tell which flowers are ripe by the colour, and only visit buds, rather than open flowers which have already been sprung. If birds don’t twist the bud, it eventually falls off unopened.
These kinds of animal-opened flowers are called “explosive” and are well known in mistletoes from Africa and India, and a few species from South-East Asia.
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