The Wonders of New Zealand Flora William Stanger
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©William Stanger ©William The wonders of New Zealand flora William Stanger Fig. 1 Silver leaves of Astelia species among the grasses on Mt Arthur n the beginning, what is and various species of trees are now threatened by I now New Zealand was Podocarpus have close kauri dieback (Phytophthora part of the supercontinent relatives in continents agathidicida). Visitors to the Gondwana. Then 85 million once part of Gondwana. forests are encouraged to years ago a large section of For example, Agathis is disinfect their shoes before Gondwana broke off and part of the Araucariaceae and after visiting, and in sailed away into the Pacific family and its relatives the some areas boardwalks Ocean to form Zealandia. Araucaria species can be have been constructed to In the process, Zealandia found in Chile, Norfolk minimise contact with sank into the depths of the Island and Brazil. There are the roots, to help protect sea and drifted away from 19 more species of Agathis these precious trees. The Australia. While mostly native to the Western Pacific majestic Tane Mahuta under the sea, it stood at the countries of Australia, (Lord of the Forest) (fig. 2) junction of the Australian Indonesia, Malaysia, is the biggest kauri in the and Pacific plates. Tectonic Philippines, Fiji, New country, 52m tall and 14m plate shifts led to a very Caledonia and Celebes, in circumference, while Te small part of the submerged Indonesian Sulawesi. Matua Ngahere (Father of continent being lifted above The NZ kauri, a close the Forest) is considered to the water line, forming New relative of the monkey be the oldest, alleged to be Zealand. Over the last 1.8 puzzle (Araucaria), is the 2000 years old. million years, vast changes largest Agathis species. Much of the flora and have made the islands we Kauri forest occurs naturally fauna on these remote know today. The Southern only in the northern part islands have evolved in Alps rose up, volcanoes of North Island, north isolation; 80% of the flora, erupted, and glaciers carved of latitude 38° south, around 2500 indigenous out lakes and valleys. but it will grow happily vascular plants, is endemic. Some of New Zealand’s throughout the country. Numerous species exhibit plants provide evidence Much of the kauri forest unusual characteristics. of its history. Both the has been lost to logging Many have a divaricating kauri (Agathis australis) and land clearance, and the growth habit, their tangled 531 ©William Stanger ©William Stanger ©William Fig. 2 William with majestic Tane Mahuta Fig. 3 Pseudopanax ferox stems branching off at wide Pseudopanax crassifolius and withstand dry conditions but angles, and frequently the P. ferox (fig. 3). prefers dappled shade – an leaves do not fully expand Similarly, plants such open aspect leads to scorched and their flowers are buried as Sophora microphylla and leaf tips. in the centre of the plant. Prumnopitys taxifolia have a Of course there are Examples include Coprosma divaricating or twisted form some major, spectacular acerosa, Corokia cotoneaster as juveniles, adopting a more exceptions. Pohutukawa and Muehlenbeckia astonii. conventional shrub or tree and the northern and Two theories suggest form once mature. Whatever southern rata – known as why many NZ plants the reasons, these plants make NZ’s native Christmas trees evolved this way: either NZ’s flora one of the most – are covered in brilliant as an effective defence fascinating on the planet. red flowers in summer. against grazing moa, now- However, the flora is Interestingly, the ratas often extinct flightless birds, or not noted for colourful, start as epiphytes. to withstand the harsh flamboyant flowers. Many A number of trees exposed conditions. plants are wind-pollinated, have mast seeding with, Another common with minute, inconspicuous at irregular intervals, characteristic is that the blooms, mostly white or synchronous production juvenile leaf shape or cream; the theory is that of large quantities of seed growth habit is distinctly native pollinating insects within a plant population. different from that of are generally unspecialised, The native beeches the adult plant. Again, negating the need for an (Fuscospora and Lophozonia) unpalatable juvenile foliage array of colour and complex and rimu (Dacrydium may have been a defence patterns. Pachystegia insignis cupressinum) are examples. against browsing moa; once (fig. 4) is one of the most In some cases this produces out of reach, the foliage attractive white flowers, an abundant food source takes on its adult form to accompanied by handsome every few years for the maximise photosynthesis fleshy leaves.Libertia native invertebrates and in the strong light of the grandiflora has an abundance birds. Unfortunately, this canopy. Good examples are of small white flowers; it can occasional abundance of 254 ©William Stanger ©William ©William Stanger ©William Fig. 4 Pachystegia insignis Fig. 5 Lobelia physaloides food means a consequential soils. In more recent times, Cordyline species. abundance of introduced though, it has been realised Another feature of pest species. that gorse can be a great NZ plants is their fruit. Sadly, much of the nursery crop for native Coprosma illustrates this flora is under threat. One plants to grow through. perfectly: its fruit comes in of the biggest problems Once the natives form a an amazing array of colours, is possums, introduced canopy the gorse is shaded including white, orange, from Australia in 1837 to out, better than using yellow, red, iridescent blues, establish a fur trade. Before weed-killer. Pinus radiata is shades approaching black, you take the view that ‘all used widely in NZ forestry and translucent, milky things cute and furry must but it has escaped, changing hues. Coprosma acerosa is be saved’, remember that natural ecosystems. Alas a wonderful plant, drought this marsupial will eat just the list goes on, with tolerant and low-growing, about every part of a plant, many a futile hour spent with orange stems and which significantly affects its trying to eradicate Chilean translucent white or blue growth, providing less food flame creeper Tropaeolum( fruits occasionally with for the native fauna. Along speciosum) and Chinese intricate patterns. Many with other introduced critters privet (Ligustrum sinense). selections of Coprosma, like hedgehogs, rats and What NZ plants lack in Corokia and Pittosporum stoats, possums will eat birds’ flower power they make up can be used for topiary and eggs and chicks; it does not for in foliage texture and low hedges. The hybrids help that many native birds colour. Think of the bold, and cultivars offer a range are ground nesting. purple leaves of Phormium of foliage colours, more- Invasive exotic plants tenax Purpureum Group, original alternatives to box. such as gorse (Ulex the silver leaves of Astelia Lobelia physaloides (fig. 5) europaeus), seen covering chathamica (fig. 1) and the has incredible metallic- vast swathes of hillside, and silver clouds of Corokia purple berries. lupins (Lupinus polyphyllus) cotoneaster. Additionally, NZ is home to some can fix nitrogen, giving them there is the dramatic foliage highly ornamental grasses. a huge advantage over the of Rhopalostylis sapida Austroderia richardii (Toe native plants on poorer (nikau palm) and the native Toe) is perhaps the most 553 graceful of all the pampas garden. Wind is a major with 12ft-tall, elegantly component of the habitats curving, gently nodding hebes have evolved in, as flowerheads produced is salt. Also, many southern ©William Stanger ©William relatively early above tough NZ species experience cold mounds of evergreen foliage. weather. Philip Smith of It will tolerate wind, pollution O2 Landscapes has trialled and apparently deer. Happy hebes in Auckland’s mild in sun or part-shade in climate: with the main moist soil, it can tolerate criterion a dense habit, some drought. Chionochloa the best species were has a graceful tussock form H. parviflora, H. stenophylla, and C. flavicans is further H. diosmifolia, H. pubescens enhanced by a weeping subsp. sejuncta and H. habit. They do best in an treadwellii. Fig. 6 Cyathea medullaris open aspect with good Other highly notable air movement. C. f. forma flowering plants include temata, not as common Clianthus and Sophora. Before in cultivation, is very 2001 only three species of attractive: its individual Sophora were recognised in florets have a looser, ‘frothy’ NZ, S. microphylla being a ©William Stanger ©William look, and the leaves often catch-all for a number of have a glaucous tinge. Its distinctive forms which are cliff and rocky habitats now described as distinct mean it is used to a degree species. Now there are eight of root restriction and good recognised species in NZ. air movement; in overly S. chathamica has larger and stable, seasonally damp more densely packed foliage, conditions, it can grow, it does not pass through a and die, too quickly; better divaricating juvenile phase, with a restricted root zone. and flowers at an earlier Planting on a slope will age than S. microphylla. Fig. 7 Cyathea dealbata provide good air movement. Its tubular golden-yellow Hebes are some of NZ’s flowers in spring provide most spectacular flowering an abundance of nectar for plants and a utopia native birds. for pollinating insects. There are about 200 Knowledge of where hebes fern species, ranging from ©William Stanger ©William come from is needed for 20m-high tree ferns to long term success. A hebe filmy ferns just 20mm long. may hail from a moist Unfortunately for us in the climate, but the effects UK, the more ornamental of wind and topography tree ferns, Cyathea dealbata must also be considered; and C. medullaris, are not many species of northern as hardy as the Dicksonia Hebe grow in exposed species. C. medullaris situations on sloping ground (fig. 6) is the tallest and such as cliffs, conditions has wonderful black frond Fig.