REINSTATEMENT OF INDIGENOUS FLORA IN THE URBAN
ENVIRONMENT OF NEW ZEALAND:
A CASE STUDY FOR HAMILTON CITY.
Sustainability/ Environmental Education
Paper No. 214
Antoinette van der Weerden
Antoinette.vanderweerden@wintec.ac.nz
Abstract
Loss of New Zealand’s original ecosystem is the result of rapid colonisation over the
past 200 years. (New Zealand Biodiversity, 2013). New Zealand currently retains
23% of its original vegetation much of which is in mountainous areas (Steens, M.,
Winter, D., Morris, R., McCartney, J., & Greenslade, P. 2007). Vegetation loss can be
attributed to industrial food production processes underpinned by forest clearance and
swamp drainage. A further loss was the direct result of the unfortunate introduction of
voracious pest animals such as the common brushtail possum (Trichosurus
vulpecular) (Department of Conservation, 2013). Only 1.6% of the original
vegetation is present in the Hamilton ecological district (Leathwick, Clarkson &
Whaley 1995, as cited in Clarkson & McQueen, 2004). The loss of vegetation and
associated fauna has led to a loss of landscape character.
Introduction
The rapid pace of landscape change New Zealand has experienced in the last 200
years has led to our current situation where only 1.6% of the original vegetation exists
in the Hamilton ecological district (Leathwick, Clarkson & Whaley 1995, as cited in
Clarkson & McQueen, 2004). Forest loss and subsequent habitat loss has led to some
plant and bird species becoming extinct or to precarious states of existence. Many
plant and bird species are now only found in the last vestiges of remnant bush.
The physical lay of the land has been modified through the spread of urban housing
sprawl; hills have disappeared, mutation of landform has occurred through the
creation of flat land providing efficient building platforms. These physical changes to
the landscape have further exacerbated the loss of regional landscape character.
The complete modification of the landscape, changing it from its natural state to a
homogenous sea of buildings has cost the Hamilton community their regional
character, and the locus of local indigenous stories. Hamilton City, like so many other
cities in the world is in danger of creating a landscape bent to monetary efficiency at
the expense of original form, function and biodiversity.
Aim of Study
This research was driven by the question:
How can Hamilton landowners use Hamilton’s indigenous landscape character as a
source of inspiration for local design?
A literature study has been undertaken combining the results of numerous botanical
studies conducted from 1955 to 2007. Soil types, landforms and plant species lists
have been matched and a matrix has been compiled with the purpose of mobilising
the property owner to re-instate the original indigenous flora into home garden spaces.
The study presents opportunities for indigenous flora to be reinstated in the landscape.
The increased visibility of the original flora in the home garden will reveal
Hamilton’s lost landscape character and re-dress our ecological loss. The results of
the research are there to be utilised by private landowners, gardeners and landscaper
designers operating in Hamilton City. The floristic range encompasses the indigenous
flora originally present in Hamilton. Whilst landforms and soil profiles have been lost
forever, the indigenous flora can be reinstated.
Hamilton City’s current population is 141,615 and covers a land area of 110km2
(Hamilton City Council 2013) and is located just south of Auckland in the North
Island of New Zealand (37.47S 175.19E) (Skysat 2013) It sits in the Waikato Basin
and is surrounded by mountains, Mt Pirongia to the southwest (959m), the Kaimai
Ranges to the east with Mt Te Aroha (952m) being the highest point. To the
northwest, the Hakirimata Range creates the western boundary of the basin with the
sacred Maori mountain Taupiri (288m) adjacent, separated from the range by the
Waikato River. The Waikato River, running southeast to northwest through the city,
dissects Hamilton City.
The landscape experienced by residents as they travel about their day is the result of
past dynamic volcanic forces, and subsequent river processes. The area covered by
Hamilton City consists of a variety of terrains including higher hills, flattish plains
incised with gullies, and escarpments running along the edge of gullies and the
Waikato River.
Provision for restoration of the gully system network is well provided for with the
development of the Gully Restoration Guide (Wall, K. and Clarkson, B. 2001). Gully
systems have mixed ownership between the Hamilton City Council and private
owners. It is the area between the gullies where the majority of the Hamilton
population lives and is the focus of this study. The results of this study are
supplementary and support the Hamilton Gully Guide information already available.
The focus of this paper is to propose a method to continue the redress of the lost
landscape character and biodiversity currently evident in Hamilton City, New
Zealand.
Following is a brief description of the site and discussion of the method used to
complete this study.
Methodology
Soils maps and plant lists have been brought together for the Hamilton homeowner.
This enables precious and valuable scientific information to become accessible for all.
Soils maps
As Hamilton’s political boundary has grown over the years the original soils map
drawn up by the NZ Soils Bureau (Bruce, 1979) for Hamilton City needed to be
extended. Original hand drawn maps by pedologist G. Orbell, and earlier soils maps
from Waipa District to the south (Grange, Taylor & Sutherland, 1939) have been
combined with the NZ Soils Bureau map for Hamilton (Bruce, 1979) to create a full
soils map for the current Hamilton City boundary (Fig.1).
The current road grid has been laid over the soils mosaic allowing residents to locate
their properties and identify their soil type. By enabling residents to locate and
describe their soil type, a closer connection to the place they live is garnered.
The soils pattern of Hamilton City is an expression of the process through which the
soils were lain down. The deposition of alluvial material by the Waikato River from
the volcanic centre in the North Island, past volcanic activity and natural
decomposition processes has produced the present soils systems of today.
The resulting soils range from deep organic peats (Kaipaki and Rukuhia soils), to the
mineral soils of the alluvial plains, (Horotiu, Te Kowhia and Te Rapa soils), the
porous soils along the river margins and lower terraces (Tamahere and Waikato soils)
and the heavier clay soils of the older Hamilton hills (Hamilton and Kainui soils),
which protrude through the wash of alluvium. In amongst all of these are intergrades.
Fig 1. Soils map of Hamilton City. Drafted by Max Oulten,
Cartographer, University of Waikato
Vegetation
Remnant areas of indigenous forest are few in the City. Currently according to
Clarkson, B., Clarkson, B., & Downs, T. (2007) there are no remnant areas of
vegetation existing for the ridges of the alluvial plains or terrace scarp ecosystems
Swales of the plains are represented in an urban forest remnant in central Hamilton, at
Claudelands Bush. A small pocket of indigenous flora exists to the south of the city
along the banks of the Waikato River at Hammond Park and represents fragments of a
gully eco-system. The vegetation of the older hills of Hamilton is represented by a
fragment of untouched forest to the north of Hamilton, Pukemokemoke Reserve.
Peat lands have a small number of sites that represents them. Although farming is
dominant, there is motivated awareness of the preciousness of these peat lake areas.
The original plant range of the region can be described as being a mix of broadleaf
and conifer forests on the higher hills and alluvial plains, with more herbaceous peat
land plants including the locally indigenous peat forming restiads Sporadanthus
ferrigineus and Empodisma minus found on the organic soils of the plains.
River and gully edges are typically drier and carry a hardwood and shrubby mix of
plants.
Plant lists
As mentioned above there is little left of Hamilton’s original flora cover. The
Hamilton community is privileged to have had eminent botanists in the past and the
present who have noted plant species, records having been kept by Botanical Societies
and keen plants people.
Plant lists have been compiled from past botanical surveys (Clarkson, B.D. 2001,
Clarkson et al, 2007, De Lange, P.J.1996, Gudex, M.C. 1955, Whaley, P., Clarkson,
B., & Smale, M. 1997), and from personal observations of these previously surveyed
areas.
Plant lists have been categorised based on the soils types and correlating landforms
and is predominantly based on the previous work of Clarkson et al., (2007). Cultural
plant details have been drawn from two main sources, Oratia Plant Nursery (2013)
and New Zealand Plant Conservation Network, (2013) and supplemented by the local
and personal knowledge.
The matrix developed as a result of this study indicates landscape uses and includes
forms such as groundcover, hedging, tall narrow spaces, scent, and habitat; and also
provides a textural guide.
Theoretical Context of the Study
The theoretical context of this study is couched on the premise that landscape
character is distinct from region to region and gives each place its own identity. In a
global world where difference is disappearing, it is critical to re-instate local
difference. This is important for people’s sense of identity and happiness. (Hough,
1990)
The concept of landscape character is not a new one, but continues to be a deeply
powerful one. Landscape character is about reading the nature of the place (Lucas
1995); understanding the underlying systems that plants represent. The biota is the
language of that place. It tells us about the soil type, landform, water regime, aspect,
geology, altitude and latitude; the original vegetation and living components present
conveys a wealth of information specific to that place. The array of these ecosystems
gives us the original character New Zealand once had and provides us with a treasure
box of possibilities in our own home gardens.
Over 20 000 exotic plants have been introduced into New Zealand over the last 200
years, overwhelming our own 2500 native vascular plants, (Ignatieva, M., Meurk, C.,
van Roon, M., Simcock, R., Stewart, G. 2008.) Widespread clearance of our native
plant cover by early land managers has rendered Hamilton’s original landscape
character as being barely legible.
Meurk and Swaffield (2007) point out “Indigenous nature may be under severe stress
from introduced species and human disturbance, whilst urban society itself frequently
assigns pre- eminence to introduced cultural forms and species”(p.11).
Homeowners, gardeners and landscapers’ preference for exotics does not reflect the
true nature of Hamilton City. Whilst cultural layers are present, it is the original plant
and biotic range that expresses a deeper connection with the original character of
Hamilton’s landscape
Ignatieva et al., (2008) suggest that the most effective place to make a difference to
our biodiversity is close to home, where it is visible to the urban community.
Meurk and Swaffield’s (2007) multi-scale strategy for creating biodiversity
opportunities in cities addresses the private spaces of the city and suggests they are “a
critical element in sustaining interpatch dynamics and supporting fine scale meta
populations of species that need high levels of management. They are the home of the
culturally induced biotope including gardens…”(p.15) While the suggestions made by
Meurk and Swaffield in their table of indigenous substitution introduces the
indigenous biotope to the cityscape, they are not region specific, whereas the previous
work done by Lucas (1995) are local to place and soil type.
Lucas (1995) develops a plant range and an ecosystem ‘signature’ for each ecosystem.
This allows easy and clear identification of an ecosystem and puts the science of
botany, geology hydrology and ecology into a pictorial construct, appealing to a
visually oriented audience and translating science into an accessible form.
The results of this study is a plant list linking soil type and indigenous plants to the
places people live; private land owners.
Plant use suggestions are made for gardeners, suggestions that offer an indigenous
substitute for the exotic. Ecosystem signatures will be developed in the same way as
Lucas (1995) allowing full and easy appreciation of each ecosystem type. These
indigenous plants are true to place whilst also fitting the required landscape structure.
The plant matrix developed covers all soil types. Below is an example of the matrix
for the peatland plains ecosystem; Kaipaki Soils (Fig.2). Other tables will be available
covering all the ecosystems present in Hamilton City.
Fig. 2. Peatland Plains Ecosystem Plant Matrix
Conclusion
While New Zealand has approximately 20000 exotic plants, the 2500 original
native vascular plants have not been fully investigated for their potential in satisfying
common garden design requirements.
Meurk and Swaffield (2007) create an invaluable framework for the successful
introduction of indigenous flora into any city and Lucas (1995) gives robust details of
this concept for Christchurch
The matrix developed for Hamilton City is based on the original flora and suggests
ways of incorporating this flora into residential garden. For each ecosystem type,
plants have been identified and also assigned roles typically found in the home
garden. These landscape uses include the following: small trees for small spaces, trees
for narrow spaces, hedging and topiary, scent, texture and habitat for local indigenous
fauna.
The re-introduction of our native flora into typical garden scenarios can replace the
exotic choices, provide habitat for our local fauna and begin to re-instate local
landscape character, which has been eroded away but is critical for local identity.
Plants are the first step in restoring an eco-system; associated factors of the ecosystem
will follow.
Acknowledgements: Thanks to Eric Haycock (Wintec) and Bruce Postill
(Department of Conservation) for guidance and Peter Morris for expert information.
References
Bruce, J. G. (1979). Soils of Hamilton City, North Island, New Zealand. New Zealand
Soils Survey Report No. 31. New Zealand Soil Bureau, Department of
Scientific and Industrial Research, Wellington, New Zealand.
Clarkson, B.D. (2001) Indigenous Vascular Plants of Pukemokemoke Reserve. Centre
for Biological and Ecology Research, University of Waikato, Hamilton, New
Zealand.
Clarkson, B., Clarkson, B., & Downs, T. (2007). Indigenous Vegetation Types of
Hamilton Ecological District. Centre for Biodiversity and Ecology Research.
University of Waikato, Hamilton, New Zealand.
Clarkson, B. & McQueen, J. (2004) Ecological Restoration in Hamilton City. Paper
presented at Greening the City Conference. Retrieved from
http://www.rnzih.org.nz/pages/2003_Conference_Proceedings_PDFs/11_Bruce
_D_Clarkson.pdf
De Lange, P.J. (1996). Floristics and Microclimate of Hammond Bush, a Hamilton
Basin Forest Remnant. Wellington Botanical Society Bulletin 47, 63-80
Department of Conservation, 2013.
Retrieved from http://www.doc.govt.nz/conservation/threats-andimpacts/animal-pests/animal-pests-a-z/possums/facts/
http://www.nzpcn.org.nz/
Grange, L.I., Taylor, N. H. & Sutherland, C.F. (1939). Soils and agriculture of Part
Waipa County. Government Printer, New Zealand.
Gudex, M.C. (1955). The Native Flora of Claudelands Bush. Transactions of the
Royal Society of New Zealand 83(3), 313-319
Hamilton City Council. (2013). Retrieved from
http://www.localcouncils.govt.nz/lgip.nsf/wpg_url/Profiles-Councils-HamiltonCity-Council-Main
Hough, M. (1990). Out of Place. Restoring Identity to the Regional Landscape. Yale
University Press, New Haven.
Ignatieva, M., Meurk, C., van Roon, M., Simcock, R., Stewart, G. (2008) How to Put
Nature into Our Neighbourhoods. Application of Low Impact Urban Design and
Development (LIUDD) Principles with a Biodiversity Focus for New Zealand
Developers and Homeowners. Landcare Research Science Series No. 35
Lincoln, New Zealand: Manaaki Whenua Press.
Lucas Associates (1995). Indigenous Ecosystems of Otautahi Christchurch Set1-4
Christchurch Otautahi Agenda 21 Committee, Christchurch, New Zealand.
Lucas, D. (1996). The nature of a place Landscape New Zealand Jan/Feb 13-15
Meurk, C.D & Swaffield, S.R. (2007). Cities as Complex Landscapes: biodiversity
opportunities, landscape configurations and design directions. New Zealand
Garden Journal 10: 10-20
New Zealand Biodiversity. (2013). Retrieved from
http://www.biodiversity.govt.nz/picture/biodiversity/state/destruction.html
New Zealand Plant Conservation Network. (2013). Retrieved from
http://www.nzpcn.org.nz/
Oratia Plant Nursery. (2013). Retrieved from http://www.oratianatives.co.nz/
Skysat. (2013). Retrieved from http://www.skysat.co.nz/LatLong.asp
Steens, M., Winter, D., Morris, R., McCartney, J., & Greenslade,P. (2007). New
Zealand's giant Collembola: New information on distribution and morphology
for Holacanthella Börner, 1906 (Neanuridae: Uchidanurinae), New Zealand
Journal of Zoology, 34:1, 63-78
Wall, K., & Clarkson, B.D. (2001). Gully restoration guide – A guide to assist in the
ecological restoration of Hamilton’s gully systems. Hamilton City Council,
Hamilton, New Zealand.
Whaley, P., Clarkson, B. & Smale, M. (1997). Claudelands Bush: Ecology of an
Urban Kahikatea (Dacrycarpus dacrydioides) Forest Remnant in Hamilton, New
Zealand. Tane 36,131-155
Figures
Figure 1. Oulten. M. 2011. Cartographer University of Waikato
Figure 2. van der Weerden, A. 2013. Plant matrix for Kaipaki peatland ecosystem.