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Home , Dacrycarpus dacrydioides, Halocarpus kirkii, Lepidothamnus laxifolius, Manoao, Metrosideros bartlettii, Metrosideros robusta

’S NATIVE

John Dawson & Rob Lucas with Jane Connor

Contributions by Patrick Brownsey, Shannel Courtney, Peter de Lange, Phil Garnock-Jones, Mark Large, Don Morrisey, Barry Sneddon To our grandchildren: Contents Lucas and Noah Dawson; Angelina and William Hayter; Grace and Francis Lucas The authors and contributors 7 Clianthus 184 Authors’ preface and Coprosma 188 acknowledgements 9 Cordyline 220 Publisher’s preface and Coriaria 230 acknowledgements 10 Corokia 232 About the book 12 Corynocarpus 233 Map of the 14 Discaria 236 Map of the 15 Dodonaea 238 Dracophyllum 240 Introduction 17 Dysoxylum 256 Elaeocarpus 260 36 Elingamita 264 Introduction to conifers 38 Entelea 266 Agathis 46 Fuchsia 268 56 Geniostoma 270 62 Griselinia 272 66 Hedycarya 276 First published in 2011 by Craig Potton Publishing 72 Hoheria 278 Reprinted 2011 Libocedrus 74 Homalanthus 290 Craig Potton Publishing 79 Ixerba 292 98 Vickerman Street, PO Box 555, Nelson, New Zealand 81 Knightia 294 www.craigpotton.co.nz 88 Kunzea 298 Text © John Dawson and Rob Lucas (unless specified otherwise) Prumnopitys 96 Laurelia 302 Photographs © Rob Lucas (unless specified otherwise) Leptecophylla 306 ISBN: 978-1-877517-01-3 (standard edition) Ferns 102 Leptospermum 308 978-1-877517-65-5 (deluxe edition) Introduction to tree ferns 104 Leucopogon 312 Publisher: Jane Connor 110 Litsea 314 Editorial: Jane Connor, Sue Hallas Dicksonia 118 Lophomyrtus 317 Index: Diane Lowther Macropiper 320 Design and layout: Jane Connor, Tina Delceg Prepress: Alan Bridgland, Spectra Graphics Flowering Trees 122 Melicope 323 Cover typography: Neil Pardington Introduction to flowering trees 124 Melicytus 326 Cover image: ‘Mist over Lake Mapourika’, © Andris Apse Ackama 132 Meryta 336 Printed in China by Everbest Printing Co. Ltd Alectryon 136 338 Alseuosmia 140 Mida 352 This book is copyright. Apart from any fair dealing for the purposes of private study, research, criticism or review, as permitted under the Copyright Act, no part may be reproduced by any Archeria 142 Myoporum 354 process without the permission of the publishers. Aristotelia 144 Myrsine 357 Ascarina 147 Neomyrtus 369 Avicennia 150 Nestegis 370 In keeping with its commitment to supporting science education, the Dick Roberts Community Trust Beilschmiedia 155 376 generously contributed the cost of donating copies of this book to all New Zealand secondary, intermediate and composite schools to mark Conservation Week 2011. Craig Potton Publishing wishes to also acknowledge Brachyglottis 160 Olearia 394 the generous contribution from Nelson Industries to the costs of publication. Carmichaelia 174 Pennantia 436 All other acknowledgements are on pages 9 and 11. Carpodetus 182 Pisonia 440 Pittosporum 442 Streblus 530 Plagianthus 463 Syzygium 536 Planchonella 466 Toronia 538 Pomaderris 468 Urtica 540 Pouzolzia 472 Veronica 542 The authors and contributors Pseudopanax 474 Vitex 552 Pseudowintera 498 Weinmannia 555 Quintinia 502 Raukaua 504 Appendix 560 Dr John Dawson was Associate Professor of Botany at Victoria Rhopalostylis 508 Glossary 562 University until his retirement in 1988. Since then, he has been undertaking botanical research in , exploring its Schefflera 512 Bibliography and further reading 565 botanical links with New Zealand and researching its largest Solanum 514 Index 570 family, . He has formally described about a quarter of the Sophora 516 c. 250 species of Myrtaceae in New Caledonia, has published two accounts of these and completed a third. John also runs extension courses on New Zealand native and guides groups around List of Boxes Otari Native Botanic Garden in Wellington. He is the author of many Beech gaps 25 Pollinators of Hoheria 279 papers on aspects of New Zealand flora, in particular the Apiaceae, and several books, including New Zealand’s conifers 38 Identification: Rewarewa and Forest Vines to Snow Tussocks: The story of New Zealand plants (1988) and Seasons in the Forest Inside a kauri forest 48 hīnau 297 (with photographs by Brian Enting, 1990) Kauri dieback 52 Kānuka and mānuka 301 Epiphytes 54 Trunk buttresses 305 Rob Lucas lectured in horticulture at The Open Polytechnic of Freshwater swamp forests 58 Mānuka blight 310 New Zealand until his retirement in 2006. He has been photograph- Rimu and kākāpo 65 Mānuka and mycorrhizae 311 ing plants for several decades, and his photographs have been widely Identification: Libocedrus bidwilli Kawakawa moth 322 published in books and magazines. He is the author of Managing and L. plumosa 78 The māhoe stripper 334 Pests and Diseases: A handbook for New Zealand gardeners and co- Identification: Mountain tōtara Australian Myoporum 355 author (with Isobel Gabites) of The Native Garden: Design themes and lowland tōtara 94 Sexual expression and flower from wild New Zealand (1988). Identification: Cyathea and variation in Nestegis 371 Dicksonia 104 Identification: Black and Epiphytes on tree ferns 107 white maire 373 John Dawson and Rob Lucas are co-authors of the award-winning Nature Guide to the New Zea- Tree ferns 108 Inside a beech forest 378­–9 land Forest (2000), Lifestyles of New Zealand Forest Plants (1993), Lifestyles of New Zealand Coast Identification: Hutu and pukatea 148 Thieving from a thief 379 and Mountain Plants (1996) and The Nature of Plants: Habitats, challenges and adaptations (2005). The lifestyle and ecology Cyttaria fungus on silver beech 382 of mangroves 152 Mistletoes 385 Jane Connor has been Managing Director and Publisher at Craig Potton Publishing since 2007. She has many years’ experience editing, designing and publishing books on plants, both in Tree daisies 160 What is treeline? 388 New Zealand and internationally. She co-founded Godwit Press and was later Publishing Direc- Magpie moth and Brachyglottis 171 Scale insect—honeydew— tor of Random House New Zealand, before moving to North America, where she was Publisher of kakabeak 185 sooty mould story 391 and Executive Vice-President of Timber Press in Portland, Oregon. Domatia 189 Hybrids in Olearia 399 Tree species of Coprosma 190–1 Moths and the twiggy olearias 428 Dr Patrick Brownsey is a leading authority on the ferns of New Zealand, Australia and Plagianthus and Hoheria 465 Identification: Coprosma the Pacific. He is a Research Fellow at the Museum of New Zealand Te Papa Tongarewa in Wel- arborea and C. spathulata 193 Five-finger as epiphytes 477 lington, and is currently working with staff at Te Papa and Landcare Research in Stipules 199 Juvenile and adult forms 489 to prepare an electronic . Cabbage tree decline 224 Patē and five-finger 512 How cabbage trees make Kōwhai caterpillar and moth 521 Shannel Courtney is a Nelson-based plant ecologist, who has worked with the Depart- their trunks 225 Witches’ broom on Streblus 533 ment of Conservation since 1987, currently specialising in threatened plants. He has an MSc in Cabbage tree moth 229 Tree nettle and butterflies 541 plant ecology, and botanical survey work in Northland, East Cape, Taranaki, Wellington, Nelson, Pulvini 257 Pūriri moth 554 Marlborough, Canterbury and on the Chatham Islands has provided him with a good working Caulifory and ramiflory 259 Tōwai and makamaka 558 knowledge of regional floras. In 2008, he was the recipient of the Loder Cup for his contribution to native plant conservation.

7 Dr Peter de Lange works as the Threatened Plant Scientist for the Department of Conserva- Authors’ preface and acknowledgements tion. Based in Auckland since 1993, his work includes plant biosystematics, cytology, ethnobotany, threatened plant management, and threat classification systems. A Fellow of the Linnean Society (FLS), Peter is the author of 14 books and 120 scientific papers. He has a particular interest in the conservation and documentation of island floras, and he has worked on the Kermadec Islands, Our forebears’ relentless destruction of large tracts of native forest is something most of us nowa- the Chatham Islands and many of the smaller offshore islands of northern New Zealand. days deplore. Given our now-comfortable lifestyles, it is easy to have this attitude—particularly when we survey the eroding hills and valleys, rapidly aggrading river beds and silt-filled waterways Dr Phil Garnock-Jones is a plant taxonomist and Emeritus Professor of Botany at Victoria that this destruction brought about. University of Wellington. After completing his PhD at the University of Canterbury on the tax- New Zealand’s early settlers were fearless forest-fellers—but they had to be. We, too, would onomy of Parahebe (now included in Veronica), he worked for 20 years at Botany Division, DSIR. have seen the world quite differently if we had been living in a flimsy, hastily cobbled-together Between 1994 and 2009, he was Professor of Plant Science at VUW, and taught botany and evolu- hut in the densely forested Hutt valley in the mid-nineteenth century. Given their pressing need tion. He has published 90 papers, mostly on the and phylogeny of New Zealand plants. for shelter and security, is it realistic for us to expect them to have taken a more conservation- minded approach to tree felling and forest destruction? Probably not. Dr Mark Large is a biologist with an interest in fern evolution and paleobotany spanning 30 As our living conditions have improved, so too has our relationship with our landscape, in- years. He has authored many publications, including Tree Ferns (2004) with John Braggins, and cluding our native trees and forests. We have belatedly realised that, if we don’t act now, a lot of acted as botanical consultant for the popular television series ‘Walking with Dinosaurs.’ He is cur- what we have previously taken for granted will soon vanish—forever. What’s more, we’ve learnt rently working, with Professor Peter Lockhart, on a book on the evolution of New Zealand plants. that our native forests must be treated with respect. Some of this is driven by the practical need to heal the landscape and improve water quality, but some is less tangible—it’s an acknowledge- Dr Don Morrisey is a marine biologist with the National Institute of Water and Atmospheric ment that what we’ve got is beyond quantifying; it’s bigger than all of its parts and bigger than us, Research (NIWA) in Nelson. His main research interests include benthic ecology, such as the too. Belatedly, too, we now realise that what we have is not replicated elsewhere in the world—it environmental effects of marine farms, and biosecurity. He has published research papers and is truly unique. reviews on the ecology of temperate mangroves, including the ecological implications of man- Standing tall within many of our landscapes are the native trees, some of which probably date grove spreads. back 80 million years, to the time New Zealand rafted away from Australia as the Tasman Sea developed. For of all our natural plant communities, it is the forests and their trees which attract DR BARRY SNEDDON lectured in botany and managed the H.D. Gordon Herbarium at Victoria the most attention and reverence. University of Wellington until retiring in 2000. He then worked for seven years as a collection This book profiles all our native trees, from the massive giants to the inconspicuous species that manager at the herbarium of the Museum of New Zealand – Te Papa Tongarewa. His main bo- rarely or barely reach tree stature. It is packed with photos and written descriptions that include tanical interests are the -plant flora of New Zealand and herbaria. notes on the ‘bigger picture’—pollination, seed dispersal, insect interactions, traditional uses and the like. We hope that all New Zealanders can open and enjoy our book and that it becomes a favoured reference for all those involved with nurturing and revegetating our landscapes, those who grow them for pleasure or profit and, not least, those who just love our native trees and wish to get to know them better. During the book’s nearly seven-year gestation period, we have enjoyed the support and en- couragement of many people. We list, with our thanks, many of these below, but we are aware that, inevitably, some names will have been inadvertently missed. If you are one of the missing, please accept our grateful thanks—and apologies. Jill Broom, Patrick Brownsey, Eleanor Burton, Matt Calder, Janeen Collings, Shannel Courtney, Mark Davis, Peter de Lange, the late Arnold Dench, Rewi Elliottt, Pat Enright, Esme and Don Finch, Lisa Forester, Kerry Gillbank, Brian Halliday, Barry and Jane Hart, Cathy and Raymond Hayter, Neil and Irene Hayter, Peter Heenan, Wendy Holland, Olaf John, James Jones, Nicola McDonald, Jenny and David McLaren, Tom Myers, Tim O’Leary, Leon Perrie, Wayne Peters, Chris and Brian Rance, Viv and Bruce Sampson, Tony Silbury, Philip Simpson, Barry Sneddon, Adele and Sid Stewardson, Andrea Townsend, Maureen Young. And finally, to our wives: Sharon, who after nearly seven years has had the dubious pleasure of discovering that, yes, she still has a husband. (RL); and Judy, who is as relieved as I am that we can now turn our attention to other things (JD). JOHN DAWSON AND ROB LUCAS

8 9 by this family, whereas Australia and New Caledonia both have many the base of the trunk resulting mainly from the accumulation of species (in six and eight genera, respectively) of , but discarded bark flakes. the family constitutes a smaller percentage of their floras. Conifer ­ is referred to as softwood and that of flowering The cypress family, or Cupressaceae, comprises c. 28 genera and trees as hardwood, because of their comparative hardness. However, 136 species in the Northern and Southern hemispheres. Two spe- there are some striking exceptions, such as the softwood yew (Taxus introduction to conifers cies of Libocedrus are New Zealand’s only members of this family. baccata), which has timber nearly as hard as that of the hardwood The third New Zealand conifer family is Araucariaceae, an ancient oak (Quercus robur), and the hardwoods balsa (Ochroma pyramidale) family now largely restricted to the tropics and subtropics of the and the New Zealand native whau (Entelea arborescens, page 266), What is a conifer? Southern Hemisphere, excluding southern Africa. The family was whose timbers are both softer and lighter than any conifer . widespread in both hemispheres in the Mesozoic Era but disappeared Softwoods consist of more than 90 percent water-conducting cells Conifer is a Latin word for ‘cone-bearing’ and alludes to cones being New Zealand’s indigenous conifers are in three families and 10 from the Northern Hemisphere at the time of the extinction of the or tracheids, and are more uniform and less complicated in structure the typical reproductive structure of this group of plants. Conifers genera (see table below); there are 20 species, all of which are en- dinosaurs in the Cretaceous. There are three genera—Araucaria, than hardwoods because they lack the fibres and specialised water- are the largest of the four groups of plants that constitute the gym- demic. Eighteen of these are trees, or can form trees in favourable Agathis and the recently discovered Wollemia—and 35 species, conducting vessels present in most hardwoods. nosperms. They are derived from a unique common ancestor in the situations, and two are low shrubs. ranging from South America to New Zealand, New Caledonia, The conifers most preferred for their timber have wood that is late Palaeozoic Era (300+ million years ago). Conifers are separated New Zealand’s conifers are dominated numerically by the family Australia and Southeast Asia. , the kauri, is the only strong, straight-grained, easily worked and naturally durable (or from the other gymnosperm groups and from the angiosperms by Podocarpaceae, with 17 (85%) of the 20 species and eight (80%) New Zealand representative. easily made durable by preservative treatment). The most valued the following shared features: of the 10 genera belonging to this family. It is mainly a Southern native conifer timbers include kauri, tōtara, rimu, mātaī and miro. • Scale- or needle-like , or forms that have been derived Hemisphere family, with representatives in Australasia (where New Tōtara and silver pine timbers are exceedingly durable in the ground, from them. Zealand, Tasmania and New Caledonia, especially, are centres of Trunk, bark and timber with both timbers rated in the highest natural durability category • Water- and food-conducting cells that are less specialised than diversity), Southeast Asia and southern Japan, Central and South In most conifers, the trunk is cylindrical and tapers distinctly of ‘very durable’ (> 25 years). However, only recycled native timber those in flowering plants. America, and sub-Saharan Africa; there are c. 18 genera and 156 upwards. Large trees of some species, such as kahikatea, can have or fallen trees can be used nowadays. • Pollen grains that either have 2–3 wings (air bladders) or are species in the family. Among New Zealand’s Pacific neighbours, the buttressed and fluted trunks. Other conifers, such as kauri, have wingless and nearly spherical; their surface can be granular islands of New Guinea and Fiji have conifer floras similarly dominated massive columnar trunks that barely taper throughout their length, or smooth, and they mostly contain more than three cells. In root systems of conifers which can be up to 30 m in kauri. comparison, the pollen grains of angiosperms lack wings, vary The bark of conifer species varies considerably, especially on ma- Conifers usually have a shallow, wide-spreading root system that widely in shape and surface sculpturing, and contain only two NEW ZEALAND’S CONIFERS ture trees. Most species have smooth bark on young trees, varying functions to anchor the tree in the ground, and extract water and or three cells. in colour and surface irregularities such as blisters, bumps, ridges nutrients from the soil. Often the root system is plate-like, which • Female or seed cones with a unique structure (page 43). Araucariaceae and lenticels. Mature bark may be smooth, or roughened by ridges, can be seen in wind-thrown individuals. A taproot may or may Agathis australis kauri furrows and lenticels in a variety of patterns, and by the shedding of not continue to develop beyond the seedling stage; for example, Conifers are woody plants and range from the tallest tree in the Cupressaceae strips or irregular-shaped flakes. Rimu bark is shed in large, thick trees of kahikatea and kauri have a taproot, whereas in tanekaha world, coast redwood (Sequoia sempervirens), at 115 m, to small Libocedrus bidwillii pahautea, mountain cedar flakes, whereas kauri, kahikatea, mātaī and miro have smaller bark and silver pine, the taproot is weakly developed or absent. Taproot prostrate shrubs. Conifers can also claim the largest tree, giant Libocedrus plumosa kawaka, kaikawaka flakes that, when shed, leave a ‘hammer-mark’ pattern on the trunk. depth is limited by low soil-oxygen levels. Lateral roots arising from redwood (Sequoiadendron giganteum), with a maximum volume of In some conifers, the bark is papery, peeling away in long (e.g. Libo- a seedling’s primary root become the largest roots of the tree. They 1487 cubic metres; the thickest trunk, Montezuma cypress (Taxo- Podocarpaceae cedrus spp.) or short (e.g. Hall’s tōtara), vertical strips or sheets; dium mucronatum), with a diameter of 11.5 m; and the oldest living kahikatea, white pine or it can be fibrous–stringy, furrowed and often light brown, as in 1. Bark of mature rimu (), showing the distinctive tree, bristle cone pine (Pinus longaeva) at 4700 years. New Zealand Dacrydium cupressinum rimu, red pine ‘contour-map’ pattern of ridges. 2. ‘Hammer-marked’, mature bark of tōtara, and peeling away from the trunk in long, persistent strips. conifers include three very tall trees— kauri (Agathis australis), bog pine mātaī (Prumnopitys ferruginea). 3. Bark of mature kawaka (Libocedrus Many massive conifers, such as kauri, develop a mound around plumosa), which separates in long strips. rimu (Dacrydium cupressinum) and kahikatea (Dacrycarpus dac- Halocarpus biformis pink pine rydioides)—all of which can attain a height of 50 m or more; and, at monoao the other extreme, one of the smallest conifers in the world, pygmy Lepidothamnus intermedius yellow-silver pine pine (Lepidothamnus laxifolius), a dwarf shrub that rarely exceeds Lepidothamnus laxifolius pygmy pine (shrub) 30 cm in height and can produce cones on shoots only 5 cm high. Manoao colensoi silver pine, manoao The great majority of conifers, including all New Zealand species, Phyllocladus alpinus mountain toatoa are evergreen. Phyllocladus toatoa toatoa Phyllocladus trichomanoides tanekaha Podocarpus acutifolius needle-leaved tōtara Conifer FAMILIES Podocarpus cunninghamii mountain tōtara, Conifers are found on all of the world’s continents except Antarctica. In thin-barked tōtara the Northern Hemisphere, they extend to the Arctic treeline, reaching snow tōtara (shrub) their latitudinal limit at 73° N in Siberia, and in the Southern Hemi- Podocarpus totara sphere, they reach almost to the southern tips of Africa, Tasmania, var. totara tōtara, lowland tōtara Stewart Island and Tierra del Fuego (Chile), where they have their var. waihoensis southern limit at 55° S. The 546 species are divided among six families Prumnopitys ferruginea miro and 67 genera, with the currently recognised families distinguished Prumnopitys taxifolia mātaī, black pine mainly by differences in cone structure, especially seed-cone structure. 1 2 3

38 introduction to conifers introduction to conifers 39 taper and branch, and often extend outwards beyond the spread of often shed when their foliage dies, resulting in the clean lofty trunk Leaves consist of three parts: the base, which is a cushion-like the mature crown. Those of young trees can be on the surface, but (bole) below the crown of tall trees. point of attachment of the leaf to the stem; the blade, which is the usually they become buried as the trees mature, although mature The main branches of conifer trees vary from more or less green, photosynthetic part of the leaf; and the petiole or stalk, which kahikatea have long, surface laterals on swampy soils. Lateral roots horizontal to vertical, with their lateral branches and branchlets links the blade to the leaf base and is typically short in conifers. support an extensive network of fine roots and feeding rootlets near often having the same inclination as the parent branch. Horizontal Scale leaves are small, short leaves that usually lack a petiole and are the soil surface throughout the entire rooting area. In good soil, most branches can be intricately branched in the same plane, which in pressed against the stem of their branchlet. Needle leaves are much of the feeding roots are in the top 30 cm. Large lateral roots may scale-leaved conifers, such as kawaka, gives the foliage a distinctly longer than scale leaves, narrow, parallel-sided, angular or flattened produce downwardly growing sinker (‘peg’) roots, which give the frond-like appearance. Branchlets (twigs) are the current year’s in cross-section, and mostly pointed at the tip. Broad leaves are also tree access to water from greater soil depths. Rimu can have large growth of a branch and bear the youngest leaves. As branchlets age, much longer than scale leaves, flat in cross-section and often widest sinker roots up to 30 cm in diameter, which descend vertically or their leaves (which may persist for many years) die and drop off, at the middle, with curved margins that taper gradually or abruptly obliquely for 1 m or more. The feeding roots of all conifers, like while their stems gradually thicken and bark forms. Thus, if they towards the base and pointed or rounded tip. Scale leaves generally those of most angiosperms, are associated with symbiotic mycor- persist, branchlets gradually become branches. have a single mid-vein, as do needle leaves, and broad leaves have a rhizal fungi that help them to absorb nutrients such as phosphorus A few conifer genera produce two types of leafy branches called single mid-vein or numerous parallel veins (as in kauri). 7 8 (as phosphate ions) from the soil. In return, the trees provide their long shoots and short shoots. Long shoots extend the length of the The leaves of most conifers have one or more resin ducts (page 42) fungal partners with sugars (glucose and sucrose). The fine roots of branch, and short shoots are borne laterally on these, have very along their length, and there is often fibrous tissue present internally, all New Zealand Podocarpaceae bear small, swollen growths called limited stem extension and contain most of the leaves. In native which makes the leaves tough and leathery. Sometimes water-storing nodules, which have been found to contain the mycorrhizal fungi. conifers, this type of branching is seen in the juvenile stage of kahi- tissue is also present (e.g. Podocarpus spp.). The stomata (breathing katea, where slender, long shoots bear horizontally arranged, short pores) of conifer leaves, which are not visible individually without shoots several centimetres long. magnification, may be grouped in whitish, waxy bands or patches form and growth pattern of conifers Three native conifers can have an unusual form of vegetative on protected leaf surfaces as, for example, in mātaī and Libocedrus Many conifers are trees with a single trunk and a conical crown; growth in which individuals form extensive, multi-trunked patches. spp. Conifer leaves can be modified to perform specialised functions smaller trees and shrubs often have a dome-shaped crown and several Bog pine extends outwards by branch layering to form more or less other than photosynthesis, for example, they can be reduced to hard, stems rather than one trunk. When young, tree conifers often have circular patches up to 10 m across. This growth form occurs when overlapping, protective scales on resting buds (e.g. Podocarpus spp.), a regular rhythmical growth pattern: a single trunk produces tiers lower branches in contact with the ground develop roots and bend or to bracts that support and protect the reproductive structures of or whorls of spreading branches at intervals from its apical growing upwards at the tip to form new trunks, which in turn produce their seed cones. Leaves of evergreen conifers mostly live for 3–5 years, point, and the branches of the older, lower whorls generally become own horizontal rooting branches. The patches thus formed may sometimes much longer. longer and more branched than the younger branches above. This develop a hollow centre resulting from the death and decay of the 9 10 The Phyllocladus, which is represented in New Zealand by growth pattern produces the conical crown characteristic of conifers. original trunks. Silver pine and mountain toatoa form patches from three species, is very unusual among the conifers in that its photo- With age, growth of the tree apex usually becomes irregular. Some sucker shoots produced from underground horizontal branches. synthetic organs are flattened stem structures called phylloclades. conifers retain a conical crown throughout their life, but in most, Small, green leaves are present on seedlings and ephemerally on the crown broadens to dome- or vase-shaped as the tree matures, the most recent stems of adults; and minute, scale-like, curved, needles, scales and other leaf forms and some become flat-topped. The lower whorls of branches are non-functional leaves occur on the margins of the phylloclades. The leaves of conifers can be broadly grouped into scale leaves, needle (See page 81 for more detail.) 4. A young ‘ricker’ kauri (Agathis australis), with a narrowly conical crown leaves and broader forms, with a variety of intergrading shapes in and whorled lateral branches. 5. A mature kauri, with a tall, columnar between. Native conifer leaves range in length from 1–2 mm (scale trunk and a much-branched crown with branches not tiered. 6. Juvenile juvenile and adult form and foliage mātaī (Prumnopitys taxifolia), with many slender, interlacing, brownish leaves) to 10 cm and in width from c. 1 mm to 15 mm. The longest branches and small leaves. and widest leaves are those of juvenile kauri. Some indigenous conifers pass through a sometimes prolonged juvenile stage in which the young plant differs in form from the adult. Notable examples are kauri, rimu, kahikatea and mātaī. Young kauri trees have short-lived branches forming a spire-like crown, 11 12 which can persist several decades before the spreading crown of

7. Juvenile kahikatea (Dacrycarpus dacrydioides), showing two kinds of branchlets (long and short shoots) and needle leaves flattened into two rows. 8. Juvenile foliage of monoao (Halocarpus kirkii), with long, narrow needle leaves. 9. Adult foliage of yellow-silver pine (Lepidothamnus intermedius), with scale leaves arranged in a tight spiral on the branchlets. 10. Foliage and a mature seed cone of snow tōtara (Podocarpus nivalis); the undersides of the leaves show a green mid-vein flanked by white bands rich in stomata (John Braggins). 11. Juvenile scale leaves of pahautea (Libocedrus bidwillii), showing the decussate leaf arrangement. 12. Juvenile foliage of kauri, with the leaves attached in opposite pairs; later, leaves are borne singly in a spiral around the branchlets. 13. Seedling of mountain toatoa (Phyllocladus alpinus), with long, narrow true leaves (needles) and the first phylloclades, with a white bloom, forming in their axils. 14. Resting bud of mountain tōtara (Podocarpus cunninghamii) at the tip of a branchlet; the bud scales (modified leaves) protect the growing tip 4 5 6 13 14 during winter dormancy.

40 introduction to conifers introduction to conifers 41 Metrosideros PŌHUTUKAWA AND RĀTĀ Myrtaceae

There is scarcely a New Zealander who could not instantly recognise a flowering pōhutukawa, or the huge flowering canopies of the north- ern and southern rātā trees when they emblazon bush landscapes in summer. These glorious summer sights are indelibly printed into the minds of all New Zealanders. When in flower, pōhutukawa and rātā impart an almost-tropical feel to our often overly cool and temperate landscape. Pōhutukawa and rātā trees are species of Metrosideros, a genus of c. 50 species of trees, shrubs and woody vines, found in New Zealand and throughout the Pacific. Metrosideros species can also be found in New Caledonia, on Lord Howe Island, in the Solomons, New Guinea and the Philippines, and as far afield as French Polynesia and Hawai’i. A recent DNA study of Metrosideros found that the species and varieties in French Polynesia, Hawai’i and other islands are geneti- cally closely related to the New Zealand pōhutukawa, M. excelsa, and have probably evolved from it, following long-distance dispersal from New Zealand. Some of the species in these distant places look quite similar to pōhutukawa; others do not. Those that are similar in Hawai’i are notable as early colonisers of lava flows, as is the pōhutukawa on Rangitoto Island in the Hauraki Gulf. In accord with the family as a whole, the leaves are gland-dotted, and the showiest parts of the flowers are the many stamens. The flowers are brush-like, mostly bright red or shades of red, sometimes pink, yellow or white, with a single stigma and numerous stamens. Trees flower prolifically in season, and the bright-red flower colour attracts and also many insects, who feed on the abundant nec- tar produced in the cup-like structures at the centre of the flowers. Several species of Metrosideros are important sources of honey in New Zealand. There are three compartments in the ovaries, and the seed capsules split open into three valves to release the . All species of Metrosideros are particularly susceptible to browsing by possums, which can eventually kill whole populations.

OPPOSITE: A flamboyant floral statement from an optimistically poised young pōhutukawa, seemingly unfazed by wind, salt and drought, December, Coromandel Peninsula.

338 Metrosideros BARTLETT’S RĀTĀ PŌHUTUKAWA

First observed in 1975 in Radar Bush near Cape Reinga at the Pōhutukawa is the best known of the New Zealand species of Me- northern tip of the North Island by an Auckland school teacher trosideros, and it could be called the native-tree icon of the northern 1 and amateur botanist, John K. Bartlett, Metrosideros bartlettii was North Island, where it grows naturally. It is also widely planted fur- a remarkable discovery. It was not a small plant easy to overlook ther south as a garden and street tree, and has naturalised in many but a large tree, up to 25 m in height, with trunks 1 m or more in places south of its natural range. Referred to as the New Zealand diameter consisting of coalesced roots, . Bartlett noticed it because of Christmas tree, it provides a brilliant display in late December and its unusual bark, which is almost white, soft and spongy, separating January, often as a backdrop to beaches crowded with holiday-makers. in thin flakes. There were no flowers present, but leaves enabled it In nature, pōhutukawa ranges from the Three Kings Islands, off to be identified as a Metrosideros. the northern tip of the North Island, to Poverty Bay in the east and Twenty-seven trees of Bartlett’s rātā are now known growing in northern Taranaki in the west. It is a very salt-tolerant tree, and its bush remnants in valley heads on the Te Paki peninsula. They grow favoured habitat is along the coast, although it also grows along lake mostly near streams or in swampy sites, and they may be terrestrial edges in the Rotorua district. or initially epiphytic on trees, including pūriri (Vitex lucens, page 1. Leaves are longer than wide and have a tomentum of white hairs on the 552), or tree ferns. Those that are epiphytic on trees are the tallest, underside. 2. A northern seashore with pōhutukawa dominating forest standing on pseudotrunks of their coalesced roots. at the edge of the sea, Park. 3. A brilliant summer display of flowers, with new leafy shoots emerging, Tui Park. The leaves are of similar size to those of northern and southern rātā ( and M. umbellata), but they are different in other respects: they are thin in texture, narrowed to a point at the tip, with the vein network visible on the underside but no oil glands. It was not until 1984 that flowers were seen, and they were a fur- ther surprise, being small, white and looking like snow over the tree 1 crowns. The flowers are c. 8 mm long with stamens c. 5 mm long. 2 The capsules are c. 4 × 2.5 mm. Flowering is in late spring to early summer, and seed capsules mature from late summer to early autumn. The threat status of Metrosideros bartlettii is ‘nationally critical.’ 2

3 1. Shiny, pointed leaves, with a visible network of veins on the underside. 2. A branched inflorescence of small, white flowers, November, Auckland University. 3. A cluster of ripening capsules with persistent calyx lobes, February, Auckland Botanic Gardens. 4. Close view of a trunk of a tree that began life as an epiphyte on a tall tree; the bark is pale grey to white, and soft and spongy, Radar Bush. 5. A young tree in cultivation with a short trunk and a tall, wide crown, Auckland University

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Old trees are often wider (up to 40 m) than they are tall (15– time, and the pavement beneath flowering streetside trees can be 20 m), a result of their diverging branching pattern. The trunks are liberally spattered with nectar. The seed capsules are c. 7 × 6 mm. often short and can be 1–2 m in diameter, branching into many Flowering is from early to mid-summer, with capsules maturing massive secondary trunks, which are inclined or sometimes hori- from mid-summer into autumn. zontal. The bark is similar to that of northern rātā (Metrosideros Along with northern rātā, pōhutukawa has colonised the lava of robusta)—grey-brown, rough and separating in thick flakes. Rangitoto Island in the Hauraki Gulf, following its eruption a few Woody aerial roots can be abundantly produced. Those that hang centuries ago. The two species have hybridised there, and also in from spreading branches look like straw brooms; those that develop Northland, to provide a range of intermediate forms. from the trunk generally grow down to the ground, serving to partly anchor trees on cliffs. 4. A tree with massive spreading branches and aerial roots, Wellington Botanic Garden. 5. Aerial roots like straw brooms with red growing points The leaves of pōhutukawa are thick, dark glossy green, 5–10 × to the rootlets; these ‘brooms’ generally do not reach the ground, but 2.5–3 cm, with pointed to rounded tips and a dense furry tomentum on sea cliffs they do to anchor the tree. 6. Close view of leaf underside of whitish hairs on the underside, except on young plants. The twigs showing the dense tomentum of white hairs. 7. A pioneer, tiny pōhutukawa seedling established in scoria, Rangitoto Island. 8. Foliage with furry, and flowers are also furry, which confers drought- and salt-spray white buds and opening flowers, January. 9. Fully open flowers; the tolerance. yellow tips to the stamens are the pollen-containing anthers, December. The flowers are c. 3.5 cm long, with stamens c. 2.5 cm long, 10. Fully open yellow flowers, a rare colour form, December, cultivation, usually bright red but sometimes yellow, pink or white. Flowers Birkenhead.11. Mature capsules opening to reveal the many thread-like seeds, cultivation, May, Hutt valley. 12. Pōhutukawa forest on Rangitoto produce abundant nectar, which attracts and lizard (gecko) Island, with astelias growing underneath and a plant of the normally 12 pollinators. The fallen stamens can colour the ground red for a epiphytic puka (Griselinia lucida, page 274).

342 Metrosideros Metrosideros 343 Metrosideros kermadecensis Metrosideros parkinsonii The kermadec pōhutukawa only occurs naturally on Raoul Island, where it is the dominant forest tree. Like its relative the mainland This species has an unusual distribution, being most common in pōhutukawa, it is widely planted throughout the warmer, par- the northwest South Island, from Collingwood to just south of the ticularly coastal areas of the North Island, where frosts are absent Paparoa Range, in coastal to mountain forests. It is also in the upland or slight. Unlike the mainland pōhutukawa, it does not present a forests on Great and Little Barrier islands off the eastern Northland summer floral display where the canopy is aglow with flowers. The coast. In forest and in cultivation, it is a straggling shrub, although Kermadec pōhutukawa flowers sporadically throughout the year, the flowers are very striking. In open habitats, it becomes a small 2 with the heaviest flowering often occurring in the winter months. tree, up to 7 m tall, multi-trunked and tortuous, with trunks up to 1 Trees are up to 15 m tall, usually multi-trunked from the base, and 4 cm in diameter and rough bark. have grey, flaking bark. Leaves are smaller than those of Metrosideros The branchlets are square in section, and the leaves are thick, 1. The leaves are hairless, with short stalks and round bases. 2. Leaves in 3.5–5 × 1.5–2 cm, narrowing to a point. There is almost no stalk, pairs and a developing shoot at the tip. 3. A shrub with flower clusters, 1 excelsa, 2–5 cm × 1–3 cm, widest at the middle and tapering to a Percy Scenic Reserve, Lower Hutt. 4. A cluster of bright-red flowers with blunt tip, with recurved margins. The leaf underside, buds and young with opposite leaves of each pair clasping the stem. Leaves are of- long stamens, October. 5. Inflorescences with opening flower buds and stems are covered in a white tomentum, which later becomes grey. ten blistered, caused by scale-insect damage, and there is often red young capsules; note the very long styles, October. The inflorescences of this species arise below the leaves on the woody branches. 6. Mature and 1. The leaves are short and broad, with white, hairy undersides. 2. A tree The flowers are crimson, with tiny red petals and numerous showy, discoloration on the leaves. in cultivation, with a short trunk or trunks and a broad, rounded crown, immature seed capsules, November. red stamens on filaments 1.5–2.0 cm long. The persistent woody The branched inflorescences are borne on woody stems below June, Hutt valley. 3. Rough, brown bark. 4. Flower buds with bright-red the leaves. The flowers are bright crimson, 6–9 mm in diameter, petals and white, furry ovaries sit above young fruits, September. 5. Ripe capsules, which occur throughout the year, have three compart- capsules releasing seeds (left), and flower buds and flowers (right), May. ments that, when ripe, are packed with numerous tiny, slender seeds. with unusually long stamens, up 25 mm. The capsules are 6–7 mm long with strongly developed veins. Flowering is from late spring to mid-summer, fruiting in autumn.

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344 Metrosideros Metrosideros 345 Metrosideros robusta NORTHERN RĀTĀ

One of New Zealand’s forest giants, northern rātā can be common in lower-altitude conifer–broadleaf forests throughout the North Island and in the northwest of the South Island as far south as Hokitika. Like the puka (Griselinia lucida, page 274), northern rātā is a specialised woody epiphyte that eventually sends a root or roots to the ground. In this case, however, the descending roots become very massive and fuse together to form a pseudotrunk, up to several metres in diameter. This supports the northern rātā crown after the supporting tree has died and rotted away, so the rātā can end up 1 2 being taller than its host, at up to 30 m or more. A number of tree species serve as supports for northern rātā. 1. Leaves have oil glands (not visible here) and a small notch at the tip. Among conifers, the rimu is notable, also kahikatea and miro. 2. Leaf tip with a small notch and prominent vein network. 3. A branch Flowering trees include pukatea and pūriri, and it probably also with flowers in front of rough bark separating in strips, December, Hutt grows on others of its species, although this would be difficult to valley. 4. A mature, freestanding northern rātā with a trunk of coalesced roots; the original supporting tree has long since rotted away, Kaitoke determine. It has been noted that northern rātā establishes only on Regional Park. 5. The original tree in this remarkable combination was a fully mature trees whose crowns are in good light. rimu and what remains of its crown is lowermost. At the top is the flowering The small, thread-like seeds of northern rātā are blown into tree crown of a northern rātā, which established as a shrub in the rimu crown and now has massive roots descending to the ground. Immediately below crowns by strong winds. The best places for them to germinate and the rātā is the smaller crown of a puka, with big, shiny leaves and a root establish are in branch forks and on inclined branches, where a mod- descending to the ground. There are masses of nest epiphytes to the right est amount of soil has been built up by mosses, lichens and small of the puka—truly a garden in the treetops, January, Kaitoke Regional epiphytes. After a decade or two, the seedlings become small shrubs. Park. 6. Early stage of northern rātā on a rimu; the main descending root is on the right, with more or less horizontal girdling roots. 7. A tree crown Eventually, a string-like root a few millimetres in diameter descends in full flower; the dead, twiggy branches may be the result of possum to the ground, close to the tree trunk, branching a few times on the damage, December, Hutt valley. 5 6

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346 Metrosideros SOUTHERN RĀTĀ

Southern rātā tolerates cooler climates than northern rātā (Metro- sideros robusta). In the South Island, it grows in the northwest and in the Marlborough Sounds–eastern Nelson. It is abundant on the 1 western side of the island down to Fiordland, and along the south and southeastern (Catlins) coast. It is less common at scattered sites east of the divide in Otago and Canterbury. It is an impor- tant component of Stewart Island forests and on the subantarctic Auckland Islands, where it forms a low, dense coastal forest with contorted, sometimes prostrate branches. In the North Island, it is present from Te Paki south to Mt Manuoha in the Urewera Range; it is most common on and the Coromandel Peninsula. In the southern North Island, it also occurs sporadically in the Tararua Range. Unlike northern rātā, this species usually establishes on the ground where there is initially good light, such as on steep mountain slopes, ridge crests and riversides. Less often, it grows as an epiphyte with roots descending to the ground and, like northern rātā, it can stand independently after the death of the supporting tree—mostly mountain cedar (Libocedrus bidwillii, page 74). Southern rātā trees are up to 15 m tall. The trunk can be up to 1 m or more in diameter, or much more in very wet Westland habitats, 2 where descending aerial roots arise from the trunk and become fused to it. The bark is papery and separates in thin, narrow strips. 1. Note the pointed tips on the leaves; no veins except the midrib are visible on the underside. 2. Close view of leaf underside showing conspicuous oil At higher altitudes and other exposed sites on thin soils, plants can glands and the midrib as the only visible vein. 3. A mountainside beginning 8 be stunted to under a metre in height, but they are still able to flower. to colour red with southern rātā flowers in summer, January, Otira valley. way. Further up, the rātā is firmly anchored by horizontal girdling roots, which encircle the tree trunk many times. The descending rātā roots gradually become massive, and its crown enlarges and stands above the crown of the supporting tree. When the latter dies, it leaves a central cavity, or ‘treehouse’, among the rātā roots. Northern rātā has been called the ‘strangling rātā’, implying that it kills the supporting tree. However, as it establishes only on mature trees, these will be very old when the rātā itself is mature, but it is likely that their lives will be at least shortened as a result of root competition and the shading of their crowns. Northern rātā can also establish on the ground in sunny, open sites, including the scoria of Rangitoto Island. The trees here are much shorter, at 10–15 m. Their trunks are generally short and up to 1 m in diameter, with many spreading branches. In the northwest of the South Island, northern rātā can also establish on limestone outcrops, which provide a surrogate ‘host’. Their trunks are normal, 9 not coalesced, roots, and they can reach 30 m or more in height. The bark is dark brown and rough, splitting longitudinally into open to release many thread-like seeds. Flowering is from late spring thick flakes. The trunks of fused roots of epiphytic northern rātā to mid-summer, with capsules maturing from mid-summer into can be much wider, up to 2 m or more. autumn. In full flower, northern rātā can be a striking sight, the The twigs are four-angled and somewhat hairy. The leaves, in whole crown appearing to be completely red. opposite pairs, are smooth-margined and 2.5–5 × 1.5–2 cm, usu- ally with a small notch at the leaf tip. The complete vein network is 8. Close view of a cluster of flowers, December, Hutt valley. 9. Seed visible on the underside of the blade, but oil glands are not visible. capsules, with their three valves opening to release the thread-like seeds, April, Hutt valley. The flowers are up to 12 mm long, with many bright, russet-red stamens c. 3 cm long. The seed capsules are c. 6 × 4 mm and split 3

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The leaves, at 3–5 × 1.5–2 cm, are similar in size to those of Sadly, possums have wiped out southern rātā from large areas of northern rātā but are easily distinguished. They narrow to a distinct the West Coast where they are not controlled. point at the tip, and on the underside there is no vein network vis- Southern rātā has some of the hardest, densest wood in the world. ible in fresh leaves; instead, there are conspicuous spots formed by Honey derived from Metrosideros umbellata is said to be one of the oil glands. Young leaves are often bright red. The leaves are sweetly finest in the world; it is light in colour, with a distinctive, almost aromatic when crushed. The volatile oils are the reason southern salty flavour. rātā is highly flammable. The flowers, at c. 2.5 cm long, with stamens c. 2 cm long, are larger than those of northern rātā and bright red, although there 4. An emergent southern rātā crown in full flower, January, Otira Gorge. 5. Thin-crowned, spindly trees develop on infertile, skeletal soils, February, are occasional trees with yellow flowers. The seed capsules too are Mt Rochfort. 6. Windswept southern rātā canopy in flower in the Auckland larger, c. 8 × 8 mm, and quite hard. They take a year to mature and Islands; the other shrubs with bright-green foliage are Myrsine divaricata release their seeds. Flowering is from late spring to mid-summer, (page 362), January, Enderby Island. 7. A display of bright-red flowers and the capsules open in the summer of the following year. In a and pointed leaves; the yellow cups in the flowers contain nectar, January, Enderby Island. 8. Bright-red flower buds and one opening flower; note the good flowering year, southern rātā on South Island mountainsides pointed leaf tips. 9. Fissured bark with a leafy shoot. 10. Close view of seed 6 are completely red—perhaps the most spectacular of all the rātā. capsules splitting open to release the slender seeds, February, Westport.

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