The 2014 Banks Memorial Lecture: Auckland's remarkable urban forest - RNZIH
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The 2014 Banks Memorial Lecture:
Auckland’s remarkable urban forest
Mike Wilcox1
Summary blocking gutters, branches breaking tolerance of salt-laden winds; golden
Auckland is a sprawling New Zealand off or the whole tree falling over, weeping willow (Salix × chrysocoma),
city approaching 1.5 million people shading neighbours, roots cracking Lombardy poplar (Populus nigra
covering 514,000 ha, embracing or lifting pavements and affecting ‘Italica’), pedunculate oak (Quercus
both rural countryside and urban underground services, and branches robur), hawthorn (Crataegus
environments. The urban tree cover getting entangled in overhead wires, monogyna), and Australian gum trees
includes numerous small remnants of to mention a few (French et al., 1985). (Eucalyptus spp.). As the commercial
public native bush totalling 1800 ha, development of Auckland flourished,
At the time of European settlement
and private bush-clad residential wealthier citizens built stately homes
in 1840, the isthmus of central
properties; patches of man-made with big gardens and ornamental
Auckland was a bleak wilderness
native forest established mostly by trees, and some public parks came
of bracken fern and maˉ nuka scrub,
community groups in regreening into existence, with tree planting
by then only sparsely inhabited by
projects; areas of exotic woodland; a feature. Nearly all the Auckland
Maˉ ori, with pockets of harakeke or
amenity and fruit trees in home isthmus was under cultivation by
flax (Phormium tenax), raupoˉ (Typha
gardens; trees planted in streets; and 1870 but eventually the farmland
orientalis) and ti koˉ uka or cabbage
public parks and gardens, campuses, disappeared as Auckland’s population
tree (Cordyline australis) swamp
golf courses and cemeteries with a grew, to be replaced by houses and
covering the volcanic soils derived
diversity of old and historic trees. networks of streets. Some of the
from the tuff, scoria and lava of
foundation trees still remain, and
Each of these six forest types is the volcanic cones of Three Kings,
planting has continued to the present
described, and analyses made of Mt Eden, Maungakiekie (One Tree
day, in streets, gardens and parks as
species composition to determine Hill), Mt Albert, Mt Smart, Mt Hobson
the urban area has expanded.
the dominant trees to be found in and Mt St John (Hayward et al.,
Auckland. 2011). The soil was a rich and friable Of the total area of Auckland –
loam and the topography gentle, and 514,000 ha, supporting a population
Introduction
the land was progressively cleared of 1.5 million people (2011) – some
Urban forest comprises the trees
and developed for farms and market 45,000 ha (8.8%) can presently be
within a city: in parks, gardens
gardens. There were few or no considered built up or urban, with the
and streets; planted singly, in
trees present then and the earliest balance of 469,000 ha (91.2%) rural,
groups or dense stands; or of
settlers at first lived in tents or raupoˉ including 51,000 ha of islands in the
natural occurrence, both native and
huts (Campbell, 1881; Esler, 2004; Hauraki Gulf (Auckland Regional
naturalised. This comprehensive
McLauchlan, 2008). As in lower Council, 2010). It is primarily the
definition follows the American
Northland (Beever, 1981), the pre- urban area comprising residential
view (Miller, 1998), rather than the
European scrublands of Auckland suburbs and business districts that is
European concept which confines
are considered to be the result of the subject of this account.
urban forest to meaning the peri-
repeated burning during intensive
urban forest or enclaves of natural Auckland as a whole (rural and
Maˉ ori occupation over hundreds of
forest which border the city (Cliffin, urban) has an impressive 4200 public
years, destroying the forest originally
2005; Carreiro and Zipperer, 2008). parks and reserves covering about
there (Esler, 1991).
Urban forest is worth studying and 50,000 ha, including the network
understanding for its many positive A Government Garden was of rural Regional Parks. The urban
values (Payton et al., 2008), and also established in what is now The component of this Auckland Council
for the high cost of its management. Domain and was introducing and estate is a very important part of
This resource has multiple owners yet producing tree seedlings by 1842 the urban forest. Recognition and
is recognised as a shared community (Adam, 2007). Early photographs definition of the different kinds of
asset appreciated by everyone. The show that settlers planted trees for forest is a necessary starting point for
benefits are many: beauty, shade, shade and shelter on their farms a description of the Auckland urban
cooling, shelter, recreation, carbon (Johnson, 1988; Bush, 2006). Species forest. Six types have been identified:
absorption, noise mitigation, wildlife early in evidence were Norfolk
• Native bush remnants
habitat, stream protection, and Island pine (Araucaria heterophylla),
increased property values. Trees also Monterey pine (Pinus radiata) and • Native revegetation
bring problems: leaves falling and Monterey cypress (Cupressus • Exotic woodland
macrocarpa) – all renowned for their • Home garden trees
1
9 Scott Avenue, Mangere Bridge, Auckland 2022, New Zealand; mike.wilcox@xtra.co.nz
New Zealand Garden Journal, 2014, Vol. 17(1) 25• Street trees escaped fire (Esler, 1991, 2004). yet natural kaˉ nuka forest is now a
• Larger sites: trees in parks, The remnant native forests have a comparative rarity in urban Auckland.
historic homesteads, schools, diverse tree flora, with good examples While most of it was cleared away
campuses, golf courses and of kauri (Agathis australis), toˉ tara for the first farms in the early days of
cemeteries. (Podocarpus totara), kahikatea settlement, some hilly farmland on
(Dacrycarpus dacrydioides), taˉ nekaha the urban fringes, such as at Albany,
Whilst most patches of urban forest (Phyllocladus trichomanoides) and has reverted back to kaˉ nuka, and
can be predominantly classified kaˉ nuka (Kunzea ericoides), and eventually will again become mixed
into one of these categories, some broadleaved canopy trees such as native forest if allowed to do so.
reserves comprise a mixture of taraire (Beilschmiedia tarairi), puˉriri
types. For instance, many city parks Auckland’s urban bush varies widely
(Vitex lucens), karaka (Corynocarpus
have planted ornamental specimen in its condition. Some, even quite
laevigatus) and kohekohe (Dysoxylum
trees and also native revegetation small reserves, have dense canopies
spectabile). Tree ferns, especially the
shrub borders (particularly along of trees and vigorous understories,
silver fern (Cyathea dealbata), and
stream banks) and sometimes a and are reasonably free of invasive
niˉkau palm (Rhopalostylis sapida)
‘wild wood’ of naturalised exotic weeds. Such reserves effectively
are prominent in the subcanopy or
trees. Each forest type contributes absorb stormwater, help keep the
understorey. There are also some
to Auckland’s urban environment, creeks and harbours clean, are
small fragments of volcanic ‘rock
sometimes separately, but commonly attractive to native birds, and are
forest’ (Fig. 1) with species such
blending together as an entity to give pleasant for recreation. Others
as tiˉtoki (Alectryon excelsus), puka
a suburb its particular treescape and are degraded to the point where
(Griselinia lucida), mangeao (Litsea
character. The local park, school the original canopy has gone,
calicaris) and maˉhoe (Melicytus
grounds, streets, and home gardens and the forest floor is exposed to
ramiflorus).
are the core urban forest of most wind, drought and flooding. And
suburbs, sometimes intensified by furthermore, some have become local
having creeks or walkways with native garden rubbish dumps, havens for
revegetation plantings, a piece of wild cats, and are over-run by carpets
residual native bush or a woodland of choking weeds on the ground,
of exotic trees filling a gully. Every weedy climbers and creepers on
suburb or neighbourhood will have its the margins, and invasive trees and
own urban forest, and is something shrubs that have contaminated the
citizens could get to know and integrity of the forest. Possums and
appreciate, wherever they live. No rats can play havoc with the ecology
part of Auckland is without some form of native bush, affecting the native
of urban forest. animal life, and the plants. Where
Fig. 1 Withiel Thomas Reserve, Mt Eden.
This is a rare example of ‘rock forest’, the these pests, particularly the possum,
Native bush remnants main species being tiˉtoki (Alectryon excelsus), are being effectively controlled or
Embedded within the residential puka (Griselinia lucida), mangeao (Litsea even exterminated, the condition of
suburbs of Auckland are numerous calicaris) and maˉhoe (Melicytus ramiflorus).
the forest dramatically improves. A
pockets of native bush in public Photo: Mike Wilcox, 6 March 2011.
good indicator species is kohekohe:
parkland, and on private land. The pattern of Auckland’s bush it bounces back with vigorous
Auckland’s public urban bush, fragments is related to soil, regeneration in the understory when
numbering 233 separate reserves topography and past history. In brief, its foliage and fruit are not devastated
and covering 1800 ha, has come into it is that the conifers – especially by possums.
being through direct purchase, as toˉ tara, kauri, kahikatea and taˉ nekaha
gifts, or by the creation of reserves What are the most serious weeds
– occur gregariously where there
under Statute. The Local Government in Auckland’s bush remnants? To
has been past disturbance by fire or
Act and the Resource Management start with, monocotyledons: these
logging and/or where soils are poor
Act (RMA) allows for the vesting of as a group constitute a particularly
in nutrients or are poorly drained,
reserves during subdivision of land significant nuisance. Many are
while broadleaved trees – especially
for new residential areas, and the shade-tolerant and moisture-loving,
taraire, puˉriri, kohekohe, and karaka –
vesting of 20 metre-wide esplanade adapting them well for taking over
dominate on the damper, more fertile
reserves adjoining the coast or damp gullies. Wandering jew
and more sheltered sites. This pattern
inlets. Though mostly small in area, (Tradescantia fluminensis), wild
is easily observed in many of the bush
these fragments are a much valued ginger (Hedychium flavescens
reserves. In some reserves, native
component of the urban forest, often and H. gardnerianum), palm grass
conifers are presently dominant,
having high plant biodiversity and (Setaria palmifolia), walking stick
but broadleaves are beginning to
birdlife, providing protection of stream bamboo (Phyllostachys aurea),
colonise abundantly so that the forest
courses, and containing a good climbing asparagus (Asparagus
may eventually progress to a mixed
representation of the native forest scandens), elephant’s ear (Alocasia
forest with emergent native conifers
types and tree species of the region. brisbanensis), Indian shot (Canna
above a broadleaved subcanopy.
They are also popular for recreation. indica), stinking iris (Iris foetidissima),
Kaˉ nuka (Kunzea ericoides) deserves
Many are south-facing gully forests Canary Island date palm (Phoenix
special mention for its importance in
which have survived because they canariensis), and Chinese windmill
nurturing the regeneration of conifers;
26 New Zealand Garden Journal, 2014, Vol. 17(1)palm (Trachycarpus fortunei) are Native revegetation Ecologically-based manuals for
the most troublesome, with ginger In recent times there have been restoring native vegetation have
probably the worst of the lot. When it numerous community-based been published by the Waitakere
comes to dicotyledon trees and shrubs regreening projects in the greater City Council (Lucas et al., 1997) and
it is species with bird-dispersed seeds Auckland area that have restored Manukau City Council (2008). These
and shade-tolerant seedlings that degraded vegetation or bare land publications contain lists of plants
are the most regularly problematic by planting mixtures of local native suitable for planting in particular
invaders of intact bush. Monkey trees. Perhaps the best-known of ecosystems, and guidelines for
apple (Syzygium smithii), Japanese these are those on islands in the carrying out restoration projects.
hill cherry (Prunus serrulata), tree Hauraki Gulf, and a useful reference Restoring native ecosystems in
privet (Ligustrum lucidum), Chinese to the principles and techniques is Auckland has been the subject of
privet (L. sinense), Japanese spindle the guidebook by Chapple et al. experimental research (Sullivan et al.,
tree (Euonymus japonicus), loquat (2001). Several projects have also 2009) which investigated the effects
(Eriobotrya japonica), queen of the been carried out within the Auckland of planting density, choice of species,
night (Cestrum nocturnum) and urban area, examples being Western soil treatment (e.g., mulching vs. soil
elaeagnus (Elaeagnus × reflexa) Springs, Meola Reef Reserve in ripping) and proximity to existing native
are all widespread in Auckland’s Westmere, Meola Creek in Mt Albert forest. High planting densities (e.g.,
bush, mainly as contaminants in the (Fig. 2), Oakley Walkway in Point 17,000 plants/ha) coupled with soil
understorey or subcanopy, though tree Chevalier/Waterview, Hamlin’s Hill ripping quickly gave a thick canopy
privet can reach into the canopy itself. Reserve in Otahuhu, Tahuna Torea that suppressed competing weeds like
Others such as woolly nightshade in Glendowie, the Puhinui Stream kikuyu grass (Cenchrus clandestinus;
(Solanum mauritianum), brush wattle restoration project in Wiri, Seaside syn. Pennisetum clandestinum) and
(Paraserianthes lophantha) and shrub Park Landfill Rehabilitation & Wildlife helped prevent invasion by woody
balsam (Impatiens sodenii) are quick Protection Project in Otahuhu, weeds like privet (Ligustrum lucidum
to exploit disturbance and canopy Mt Smart in Te Papapa, Macleans and L. sinense) and brush wattle
gaps. Plectranthus (Plectranthus Park in Howick, Waiatarua Reserve (Paraserianthes lophantha).
ciliatus and P. ecklonii) and bartlettina in Meadowbank, Arch Hill Scenic
An issue in Auckland revegetation
(Bartlettina sordida) are common Reserve, Tuff Crater, the Kaipatiki
schemes is whether initial planting of
marginal weeds in the higher-rainfall Project on the North Shore, and
bare sites should be with just fast-
urban forest at Titirangi. the comprehensive Twin Streams
growing pioneers such as maˉ nuka,
project in Waitakere involving riparian
On the poorer gumland soils of the kaˉ nuka, koˉ huˉhuˉ, ngaio, cabbage tree
tree planting in the catchments of
North Shore and western suburbs, and karamu (Coprosma spp.), to be
Henderson Creek and Huruhuru
sclerophyllous (drought and fire followed up later, once the protective
Creek which flow into the Waitemata
tolerant) species of Australian origin thicket is in place, with tall local forest
Harbour.
are common contaminants of fire- trees such as puˉriri, taraire, tiˉtoki,
induced kaˉ nuka-dominated reserves, kohekohe, karaka, toˉ tara and rimu
the main invasive species being (Dacrydium cupressinum), or if the tall
prickly hakea (Hakea sericea), willow- trees should be planted from the outset
leaved hakea (H. salicifolia), Sydney or just left to colonise on their own. It
golden wattle (Acacia longifolia), seems from the examples discussed
black wattle (A. mearnsii), and below that if something resembling a
more rarely, cedar wattle (A. elata). natural forest is the eventual desired
Common weeds of poˉ hutukawa result, then some tall tree species
(Metrosideros excelsa) and karo need to be planted from the beginning,
(Pittosporum crassifolium) coastal otherwise the result is an artificial, man-
cliff forest are evergreen buckthorn Fig. 2 Roy Clements Treeway, Meola Creek, made shrubbery of flax, cabbage trees,
(Rhamnus alaternus), boneseed Mt Albert. Photo: Mike Wilcox, 13 Feb 2012. maˉ nuka, kaˉ nuka, koˉ huˉhuˉ, lemonwood,
(Chrysanthemoides monolifera), Common features and activities of and coastal species such as ngaio,
sweet pea shrub (Polygala myrtifolia), these forests are the deployment taupata, houpara and karo. Bergin and
Cotoneaster glaucophyllus, of volunteers to plant and maintain Gea (2005) and Bergin (2011) discuss
agapanthus (Agapanthus orientalis), the trees, the use of several native and compare various planting options,
and sometimes Indian hawthorn tree species chosen for their ease of and their ‘Scenario 4’ (concurrently
(Rhaphiolepis umbellata). The propagation and establishment and planting a mixture of native trees and
most widespread climbing weeds expected adaptation to the site, and shrubs) has considerable appeal for
include climbing jasmine (Jasminum control of weeds and animal pests. creating a native timber resource and
polyanthum), moth plant (Araujia The most popular species planted are a well-balanced ecological forest at a
hortorum) and climbing asparagus ngaio (Myoporum laetum), lemonwood reasonable cost.
(Asparagus scandens). Spore- (Pittosporum eugenioides), koˉ huˉhuˉ Exotic woodland
bearing plants, too, have weedy (P. tenuifolium), karo (P. crassifolium), This forest type is a mixed bag of
representatives, the most troublesome cabbage tree (Cordyline australis), exotic trees that have been planted as
being sword fern (Nephrolepis maˉ nuka and kaˉ nuka. woodland or have spread as self-sown
cordifolia) and selaginella (Selaginella
trees to form naturalised forest.
kraussiana).
New Zealand Garden Journal, 2014, Vol. 17(1) 27The main species involved are Monterey pine first found its way to (New Lynn), Cyclarama Reserve
Monterey pine (Pinus radiata), Auckland in the 1860s. Sir George (Massey), Wattle Bay Reserve
maritime pine (Pinus pinaster), Grey brought in seed supplied by (Lynfield), Avondale South Domain,
various eucalypts (Eucalyptus spp.), William Hooker, from Kew, in 1862 Craigavon Park (Blockhouse Bay),
black wattle (Acacia mearnsii) and – the origin of the first plantings on and also on the North Shore (e.g.,
pedunculate oak (Quercus robur), but Kawau Island. David Hay, an early Kauri Point Domain, Northcross
there are also ‘weed’ forests where Auckland nurseryman, was selling Reserve, Bushglen Reserve, Penguin
tree privet (Ligustrum lucidum; Fig. 3), Monterey pine seedlings to settlers Drive/Speedy Bush Reserve, Malters/
crack willow (Salix fragilis), Japanese in 1862, probably also derived from Helvetia Road Reserve, Woodridge
hill cherry (Prunus serrulata), monkey seed sourced from England. The Reserve, Rawene Reserve,
apple (Syzygium smithii) and woolly pine trees at Potters Park, Balmoral, Unsworth Reserve, Rangatira
nightshade (Solanum mauritianum) are thought to be among the earliest Reserve, Spoonbill Reserve and
are commonly present. surviving plantings. Another early Lyford Reserve/Sunnynook Bush)
introduction of this pine, this time and at Silverdale (Silverdale Scenic
directly from California, was by Reserve). Particularly huge wattle
McLoughlin in 1865, where a planting trees are found in the 2.3 ha Oratau
was made on his Puhinui Station in Reserve at Greenhithe; old wattle
south Auckland (Shepherd, 1990). trees in Auckland can attain a height
One of the most prominent stands of 30 m and a diameter of around
of Monterey pine in Auckland is on 80 cm, such large specimens likely
the slopes between the Auckland to be around 100 years old. Vigorous
Zoo and Western Springs Stadium. young stands of self-sown black
These were planted in 1923, and wattle have developed in Sunhill
are now a rare example of a fully Scenic Reserve adjoining Waikumete
Fig. 3 Privet forest (Ligustrum lucidum), mature plantation of this species. Cemetery. These forests also contain
Oakley Creek. Photo: Mike Wilcox, 1 Oct 2008. Other notable old stands of pines large Monterey pines and some also
Notable eucalypt woodlands occur in are the landmark grove of 45 m tall have maritime pine, and typically
Auckland at the Waikumete Cemetery, trees in Windmill Park in Mt Eden, on prickly hakea (Hakea sericea), willow-
at Waiatarua Reserve in Meadowbank, Pigeon Mountain, on Mt Wellington, leaved hakea (H. salicifolia), Sydney
in the Auckland Domain, in Cornwall at Kauri Point Domain, where a golden wattle (Acacia longifolia),
Park, at the Pupuke Golf Course in dense understorey of houpara prickly Moses (A. verticillata),
Campbells Bay, and in Fowlds Park, (Pseudopanax lessonii) has maˉ nuka, kaˉ nuka, and some
Mt Albert. The Waikumete eucalypts developed, in Unsworth Reserve, characteristic gumland species such
occur in several discrete patches, Ayton Reserves and Rosecamp Road as neinei (Dracophyllum sinclairii),
the largest of which is of Eucalyptus Foreshore Reserve (Beach Haven), Schoenus tendo and sword sedge
obliqua. There are also some stands in the Chelsea Estate Heritage Park, (Lepidosperma laterale). Willow-
of E. saligna, while numerous other in Claverdon Park (Royal Heights), leaved hakea can form dense stands,
species have been planted bordering in Oakley Creek, in Churchill Park, as in parts of Gill’s Road Reserve,
the property, the main species being in Waikumete Cemetery, in the Albany. Black wattle was originally
E. pulchella. The Waiatarua eucalypt Glendene Reserve, and in Zita Maria grown to produce tannin from the
grove is comparatively young, but Park (Massey). bark, but the plantations were
made up of 15 species in the form abandoned, though have persisted
As well as Monterey pine, Chelsea
of small individual plots. Among the for a century. The wattle-pine forest at
Estate Heritage Park has some of
best performers there are E. maidenii, Crestwood Retirement Village in Golf
Auckland’s largest trees of maritime
E. ovata, E. pilularis, E. regnans and Road, New Lynn, has the very notable
pine (Pinus pinaster). This park is
Corymbia maculata. The Auckland additional presence of long-leaved
very extensive – perhaps the largest
Domain eucalypts on ‘Eucalypt wattle (Acacia longissima) – the
exotic woodland in the city – with a
Hill’ are a mixture, with tallowwood only recorded place in New Zealand
considerable understorey of native
(E. microcorys) being particularly where this attractive Australian tree
trees (including plentiful taˉ nekaha)
impressive (Wilcox et al., 2004). has become naturalised. Parramatta
developed beneath the pines. Another
Auckland’s most famous eucalypt wattle (A. parramattensis) has
good example of a maritime pine
grove is the collection in Cornwall naturalised along the Otara Creek in
forest is Penguin Drive/Speedy Bush
Park, dating back to the 1930s. Highbrook Park, and also in Walmsley
Reserve in Murrays Bay, and there
Here there are 40 or so species Road Reserve, Mangere. Green
are stands of it, too, in Moire Park
planted line-by-line for convenient wattle (A. decurrens), conspicuous
(Royal Heights).
comparison. Many of these are now with its bright yellow flower heads in
enormous trees, among the biggest There are several old black wattle August, and silver wattle (A. dealbata)
being E. fastigata, E. microcorys, forests in west Auckland, such are sporadic in their occurrence in
E. muelleriana, E. nitens, as Moire Park (Royal Heights), Auckland, but both can be seen near
E. quadrangulata and E. smithii. Henderson Creek Walkway the eastern end of the Manukau
Coast box (E. bosistoana) is another (Henderson), Kowhai Reserve Coastal Walkway at Southdown.
good performer in Cornwall Park, (Konini), Crestwood Retirement Cedar wattle (A. elata) is likewise
forming a long shelterbelt. Village and Titirangi Golf Course sparsely distributed.
28 New Zealand Garden Journal, 2014, Vol. 17(1)The old pine and wattle forests of overhead-wire height (c. 8 m) or taller. been afforded protection under the
Auckland usually have a dense Some 1561 trees were counted and Auckland Unitary Plan. Such trees are
understorey of native shrubs, most tallied by species and suburb. The called scheduled trees, and require
commonly shining karamu (Coprosma survey recorded 145 tree species, the resource consent for felling or major
lucida), coastal karamu (Coprosma 30 most frequent species being listed surgery.
repens), Coprosma rhamnoides, in Table 1.
hangehange (Geniostoma
There were some differences
ligustrifolium), maˉ hoe, maˉ pou
between suburbs in the frequency
(Myrsine australis), mingimingi
of species, reflecting perhaps soil
(Leucopogon fasciculatus),
differences (e.g., volcanic loam
pigeonwood (Hedycarya arborea)
vs. clay), affluence, and age of the
and silver fern. Maˉ pou is particularly
suburb. For instance, big puˉriri and
abundant.
tiˉtoki trees are rarely seen in ‘clay’
Home garden trees suburbs such as Hillsborough, and
The predominant component of the there is a greater frequency of palms
urban forest is the varied assemblage in Epsom. Some streets in the older
Fig. 4 Schizolobium parahyba,
of trees planted in private gardens, parts of Mt Eden (Fig. 4), Three 29c Kingsview Rd, Mt Eden.
at the front and back of houses. A Kings and Epsom have garden after Photo: Mike Wilcox, 7 March 2009.
survey was conducted by the author garden with interesting and diverse
Street trees
in August 2008 to find out what were trees; Mountain Road, Owens Road
Street trees are a significant and
the most popular species planted. and St Andrews Road being prime
visible component of the urban forest.
Eight suburbs were sampled and examples.
Each of the former city councils
surveyed by driving or walking around
Many home garden trees of special in Auckland had a programme of
numerous streets. To be counted
merit because of their rarity, age, maintaining and planting street trees.
in the survey the trees had to be of
size and historic importance, have
Table 1 Sample of 1561 home garden trees in Auckland ranked by abundance.
Species Onehunga Epsom Mt Albert Mangere Mt Eden North Shore Remuera Hillsborough Total
Metrosideros excelsa 42 15 26 9 27 29 12 19 179
Araucaria heterophylla 10 6 14 20 7 7 4 20 88
Liquidambar styraciflua 9 13 13 6 13 14 4 12 84
Betula pendula 18 21 8 5 15 3 2 5 77
Phoenix canariensis 10 9 8 7 8 7 8 4 61
Vitex lucens 19 4 6 5 8 7 2 3 54
Cryptomeria japonica 6 4 15 3 4 3 1 11 47
Podocarpus totara 14 8 3 2 9 2 3 5 46
Cedrus deodara 6 11 9 9 2 2 3 1 43
Eucalyptus nicholii 5 6 4 11 0 0 0 13 39
Quercus robur 2 7 3 6 3 3 7 7 38
Cordyline australis 4 1 1 3 7 6 1 9 32
Syzygium smithii 8 0 6 3 3 2 2 6 30
Syagrus romanzoffiana 0 1 4 0 8 7 4 6 30
Dacrydium cupressinum 1 11 4 0 11 0 1 1 29
Grevillea robusta 5 1 4 10 1 0 1 7 29
Jacaranda mimosifolia 8 6 1 0 6 6 1 1 29
Agathis australis 10 2 5 1 5 0 1 3 27
Cupressus macrocarpa 6 0 0 6 0 1 0 8 21
Eucalyptus cinerea 2 1 1 3 0 2 1 11 21
Ginkgo biloba 4 6 0 0 4 4 0 1 19
Magnolia grandiflora 1 6 0 2 3 4 1 1 18
Casuarina cunninghamiana 3 1 3 6 0 0 1 3 17
Casuarina glauca 0 0 0 7 0 1 0 9 17
Washingtonia robusta 3 0 5 0 1 7 1 0 17
Melia azedarach 2 1 1 0 4 6 0 1 15
Banksia integrifolia 7 2 1 3 0 0 0 1 14
Fagus sylvatica 1 3 1 1 6 0 1 1 14
Populus nigra ‘Italica’ 4 3 0 0 0 1 1 5 14
Prunus serrulata 2 9 1 0 2 0 0 0 14
All others 59 71 34 50 56 38 35 55 398
Total 271 229 181 178 213 162 98 229 1561
New Zealand Garden Journal, 2014, Vol. 17(1) 29A survey was conducted by the author Table 2 Frequency of tree species in a sample of 546 streets in Auckland.
in July-August 2008 to determine Rank Species Number of streets
the predominant species planted in 1 tītoki (Alectryon excelsus) 62
residential streets. Some 546 streets 2 willow myrtle (Agonis flexuosa) 40
with street trees were sampled in the 3 Persian lilac (Melia azedarach) 39
former Auckland, Manukau, North
4 flowering cherries (Prunus campanulata & P. serrulata) 39
Shore and Waitakere cities (Fig. 5–6).
5 Australian kanooka (Tristaniopsis laurina) 38
Many streets, particularly in Manukau,
6 pōhutukawa (Metrosideros excelsa) 30
Waitakere and North Shore, had no
7 silver birch (Betula pendula) 27
street trees at all, and these were not
8 brush box (Lophostemon confertus) 23
counted in the sample, and nor were
streets that had a mixture of species. 9 London plane (Platanus × acerifolia) 19
The older inner Auckland suburbs, 10 claret ash (Fraxinus angustifolia subsp. oxycarpa 17
‘Raywood’)
such as Mt Eden and Epsom, had by 11 bottle brush (Callistemon citrinus & C. viminalis) 14
far the greatest proportion of tree-
12 evergreen magnolia (Magnolia grandiflora) 14
lined streets.
13 lemonwood (Pittosporum eugenioides) 13
14 Australian tea tree (Leptospermum morrisonii ‘Copper 11
Sheen’)
15 elms (Ulmus spp.) 11
16 pūriri (Vitex lucens) 10
17 Brazilian pepper tree (Schinus terebinthifolius) 8
18 maples (Acer spp.) 8
19 sweet gum (Liquidambar styraciflua) 7
20 Illawarra flame tree (Brachychiton acerifolius) 6
21 Australian frangipani (Hymenosporum flavum) 6
22 monkey apple (Syzygium smithii) 6
Fig. 5 Broussonetia papyrifera, High St, 23 tōtara (Podocarpus totara) 6
Otahuhu. Photo: Mike Wilcox, 18 July 2008. 24 olive (Olea europaea) 5
25 photinia (Photinia serratifolia) 5
26 kōwhai (Sophora microphylla) 5
27 Canton lace (Radermachera sinica) 4
28 broadleaf (Griselinia littoralis) 4
29 coast banksia (Banksia integrifolia) 4
30 cabbage tree (Cordyline australis) 4
31 queen palm (Syagrus romanzoffiana) 4
32 Chinese elm (Ulmus parvifolia) 3
Fig. 6 Lophostemon confertus, 33 karaka (Corynocarpus laevigatus) 3
Richmond Rd, Ponsonby.
34 Japanese spindle tree (Euonymus japonicus) 3
Photo: Mike Wilcox, 13 July 2008.
35 rewarewa (Knightia excelsa) 3
The results are of considerable 36 lime (Tilia cordata) 3
interest and when it comes to choice 37 Norfolk Island hibiscus (Lagunaria patersonii) 2
of species, size matters, and so does 38 Turkey oak (Quercus cerris) 2
shape. Seventy-five species were
39 pedunculate oak (Quercus robur) 2
recorded, the 43 commonest across
40 kusamaki (Podocarpus macrophyllus) 2
all suburbs being listed in Table 2.
41 Canary Island date palm (Phoenix canariensis) 2
The popularity of tiˉtoki deserves 42 Kermadec pōhutukawa (Metrosideros kermadecensis) 2
comment. It has been widely planted 43 puka (Meryta sinclairii) 2
on the volcanic soils of central 44–75 All others 29
Auckland, where it seems to thrive. Total 546
Furthermore, this tree is a native,
seemingly safe and harmless, it too tall. It is a species of natural Francis Street, Hakanoa Street). It
is rarely complained about, it is occurrence in eastern Australia, lining was once common practice to pollard
evergreen, it seems to grow well on streams. London plane when left to Auckland’s plane trees, but they are
street berms, it usually maintains a grow to full size is Auckland’s grandest now mainly left to grow tall (Auckland
good shape (with erect trunk and street tree, with several splendid City Council, 1997). Oriental plane
spreading, dense crown), and does avenues in the downtown area (e.g., (Platanus orientalis) is not common
not grow too fast (or too tall) so as Symonds Street, Alfred Street, Greys and not particularly successful as a
to seriously interfere with overhead Avenue, Vincent Street) and adjoining street tree in Auckland, but features in
wires. Australian kanooka is a highly suburbs of Ponsonby (e.g., Franklin the upper part of Ponsonby Road. Its
successful street tree, being of Road, Picton Street), Freemans Bay distinctive bronzy leaf tips show out in
handsome appearance, excellent (Howe Street) and Grey Lynn (e.g., summer and autumn.
health, even growth, and not growing
30 New Zealand Garden Journal, 2014, Vol. 17(1)Fig. 7 Historic p oˉ hutukawa (Metrosideros Fig. 8 Ilex cornuta, Monte Cecilia Park, Fig. 9 Ulmus × hollandica, Papakura
excelsa), Emily Place Reserve, central Hillsborough. Photo: Mike Wilcox, 7 June 2012. Cemetery. Photo: Mike Wilcox, 4 May 2012.
Auckland. Photo: Mike Wilcox, 31 Dec 2010.
Larger sites: trees in parks, historic trees (15 m or more tall) in the city Council (2003) and Wilcox (2012)
homesteads, schools, campuses, are poˉ hutukawa, eucalypts, puˉriri, list Auckland’s notable trees, and
golf courses and cemeteries toˉ tara, pin oak (Quercus palustris), the New Zealand Tree Register
Whereas home gardens and streets sweet gum, pedunculate oak, database includes several entries
are restricted by overhead wires London plane (Platanus × acerifolia), from Auckland. Wilcox (2012)
and proximity to buildings as to the monkey apple, Monterey cypress also provides a comprehensive
number and size of trees that can (Cupressus macrocarpa), Norfolk inventory of the trees to be found in
be grown, parks and reserves have Island pine (Araucaria heterophylla), Auckland, grouped by region of origin:
few such limitations as they have Monterey pine, Canary Island date New Zealand, Australia, Pacific, North
the advantage of space. The role palm (Phoenix canariensis), brush America, South and Central America,
of these places in the urban forest box (Lophostemon confertus), river Europe, Africa and Asia.
is therefore of major importance sheoak (Casuarina cunninghamiana),
Concluding remarks
for it is here we find the greatest claret ash (Fraxinus angustifolia
The forest type classification
dendrological treasure of big trees of subsp. oxycarpa ‘Raywood’), silky
adopted here as a way of describing
a great number of species (Fig. 7–11). oak (Grevillea robusta) and poplars
Auckland’s urban forest should have
Auckland’s oldest parks dating back (Populus yunnanensis, P. nigra
application in helping with managing
150 years have an assemblage of ‘Italica’, P. × canadensis). These
the forest in the future. This forest-
trees from various parts of the world, are the species that give the primary
type model should also be applicable
with Norfolk Island pine, Queensland structure to Auckland’s urban forest.
to description and management
kauri (Agathis robusta), Moreton Bay The predominant eucalypts are
of urban forest in other cities. The
fig (Ficus macrophylla), poˉhutukawa Eucalyptus botryoides, E. cinerea,
urban forest is ecologically, socially,
(Metrosideros excelsa), puˉriri, holm E. nicholii and E. saligna. The most
commercially and politically complex.
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