Landscape
design intuitively seems like an activity beneficial to the environment.[1] It preserves and celebrates green spaces even in dense urban areas; it
works with the very stuff of nature – earth, water, air, life. Starting small
and young, designed landscapes grow and mature, becoming more desirable with
the patina of age, gainsaying design’s current preoccupation with newness and
built-in obsolescence. There is little evidence here of affluenza – John de Graaf’s concept of a
contagious condition of overload and waste stemming from the constant pursuit
of more. Instead designed landscapes seem to encourage us to cherish the past,
and to wait for the future. We believe that they allow us to experience the
power of nature unsullied by human activity and development. As a result,
landscape designers can easily see themselves on the side of the angels,
custodians of ancient values in the face of modern lifestyles and material
cultures.
Yet landscape design is implicated
in resource depletion, climate change, and pollution of the soil and
groundwater supplies. As cities have grown and technology has proliferated, so
we have designed and maintained landscapes that depend on unsustainable
practices to survive. Natural ecosystems have been ignored, damaged and
destroyed, and healthy soil has been disrupted, releasing its stores of
sequestered carbon dioxide. Watercourses have been dammed or rerouted or forced
underground as large areas are paved with non-porous materials. Having been
transported from distant sources, exotic plants require the application of
chemical pesticides and frequent watering to survive, and have often replaced
native plant material, which is suppressed and even poisoned with herbicides.
Tree cover has been reduced or removed, leading to less carbon dioxide
absorption, decreased capacity for stormwater management, and less summer shade
and winter shelter for buildings. Elaborate fountains and features are installed
that consume precious sources of water and energy. Other widespread and
unsustainable practices include the production and long-distance shipping of
materials, especially cement, waste disposal in landfill, and the use of
mechanised maintenance tools (mowers, hedge trimmers, leaf-blowers, outdoor
heaters) powered by fossil fuels. Sustainable activities traditionally carried
out in gardens, such as food production, clothes drying, and composting, have
been condemned by designers as unaesthetic and moved indoors or off-site.[2]
In
addition, an increasing interest in landscape design history – and the
celebration of famous past designers – has served to encourage unsustainable
restoration and conservation procedures, and the wilful destruction and replacement
of existing landscapes.
It is easy to argue that such practices have arisen because we knew no better, that it is only recently we have grasped the environmental impact of our actions. But in landscape design, and especially in our attitudes to historic designed landscapes, there is still an overwhelming resistance to a more rigorous sustainability. This has its roots in humanity’s complex, ambiguous, contradictory relationship with nature. On the one hand, we see the natural world as the embodiment of reality and goodness, something that provides an absolute moral standard or ‘norm’ and that should be preserved at all costs. It represents an imagined essence of mankind: the good or natural impulses that we followed before civilisation and industrial development tainted us. On the other hand, nature is ‘red in tooth and claw,’ brutal, primitive, something to be conquered or overcome. In this view, civilisation has allowed us to rise above our bad, natural impulses. Both of these attitudes implicitly define nature as that part of the world not modified by people, and thus we are set apart from or against nature.[3] Coupled with this is the West's unreflexive anthropocentrism, the long-standing view of humanity as the epitome of creation, in which nature has no intrinsic value outside its role in supporting and enriching human life.[4]
In
this way of viewing the world, historic designed landscapes are – to use the
biblical terminology – examples of humanity exercising our dominion over
nature: we seek to subdue the land through design, to manipulate it into
something that provides human pleasure, that displays political power, social
class or privileged taste. Not only do we see nature as ours to
suppress, remodel and tame, but also as something which is essentially visual. All
too often, landscape design has been about simple surface
aesthetics - nature portrayed as something static and separate, some pleasant
scenery, a shallow visual decoration. The same issue, of the primacy of the
sense of sight, occurs equally in architecture, where the potential to design
buildings that offer complex, sensory explorations of fundamental aspects of
human existence (dwelling, domestication, place, time) is frequently reduced to
the production of a series of architectural images designed to be admired from
afar. In interior design as well, spaces are devised, not to nurture and echo
how people live, but as “mostly static responses to primarily visual concepts
of beauty.”[5] Indeed, in Heidegger’s view, humanity in the modern age is ignoring the
fundamental issues of existence and being, choosing to reduce the world to a
simple fixed image, so that everything is conceived and grasped as a picture.
The essentially visual view of
designed landscapes becomes especially troubling in the maintenance and
restoration of works by ‘star’ designers of the past. Historic designed
landscapes are often treated as stable, two-dimensional representations,
essentially no different from the picturesque landscape paintings that were
often their inspiration, and capable of being viewed, maintained and restored
in the same way.[6] Historic designed landscapes are thus seen as finished art, pictorial
idealised versions of nature,[7] and their visual images are painstakingly preserved as if in aspic,
despite the essential capacity of plant material to grow and evolve. Lost or
damaged features are restored or rebuilt, often at astonishing expense, and
highly artificial plant groupings are maintained through intensive cultivation,
despite the danger of such items ultimately being exotic features largely
inexplicable without their full context, like a caged animal in a zoo.[8]
Success in managing a historic designed landscape is judged on how far the site has retained its appearance since its creation (or since some other significant point in the past), as represented in photographs, drawings and plans; and on how beautiful it is considered to be. This “tyranny of the visual”[9] frequently means that any signs of native plant succession or subsequent human interaction with the landscape are ripped out. At its heart, the often extensive maintenance work seeks to conceal or suppress natural cycles of death and decay, forever presenting the landscape as green, preened and traditionally pretty. Some critics argue that this leaves historic designed landscapes as little more than “graveyards above the ground - congealed memories of the past that act as a pretext for reality.”[10]
Of course many designers and writers
have argued for more sustainable, ecologically friendly landscape design, from
Jens Jensen’s championing of native prairie style parks in
The threat of climate change has
added a new impetus to the shift towards more sustainable design. With likely
phenomena including increasing temperatures, greater numbers of heat waves,
rising sea levels, more frequent intense rainfall, and larger areas affected by
drought,[14] the impact will be as significant for designed landscapes as for any
part of the built environment. Both professional and amateur practitioners are
starting to see the need to reduce global warming through changing practices,
and to be prepared for its results: damage and destruction of landscape
features by flood, storm, fire and drought, changing patterns of vegetation,
and new distributions of pests and diseases. This growing awareness has led to
a plethora of guides and manuals for designing sustainable new parks and
gardens – from books aimed at the general public, such as Sustainable Landscaping for Dummies, to lengthy technical
guidelines on sustainable site design for American landscape architects, which
advocate the non-disturbance of healthy soils, waste reduction, the choice of
locally-grown, low maintenance plants, the reuse of materials salvaged from the
site or nearby, and the use of non-fossil-fuel-based maintenance tools. In the
In their different ways, all these efforts – regenerative development of industrial sites, eco-revelatory design, guidance on environmentally-friendly landscape practices – can be seen as part of a drive to reclaim landscape design as an exemplar of sustainable practice. But historic designed landscapes are as yet almost exempt from such considerations. Few if any historic designed landscapes are managed sustainably. Advice from preservation bodies may include environmental issues, but the main focus is still on preserving the historical appearance of designed landscapes ultimately at the expense of other considerations. Even in guidelines for the modern-day rebuilding of non-surviving historic landscapes, for instance, one national agency unequivocally recommends against “obscuring or damaging the appearance of the reconstructed landscape in the process of providing environmental protection … [or] energy efficiency.”[17] Similarly, the Sustainable Sites Initiative (an American collaborative programme that seeks explicitly to mitigate the climatic impact of designed landscapes) is struggling to find any way of balancing sustainable practices with the preservation of historic character. Its latest draft guidance simply recommends that historic designed sites should be protected, and invites suggestions on how they might be expected to contribute to sustainability.[18] Even iconoclastic designer Richard Haag (creator of the groundbreaking Gas Works Park in Seattle, in 1975, which preserved, cleansed and recycled an old industrial plant into a public park) challenged the idea of incorporating environmental improvements on a university campus because he thought such changes might compromise its historic designed character, and that would be too high a price to pay.[19]
Such judgments about the preeminence
of history are pervasive. John Ruskin expressed views still held by many today
when he portrayed historic designed landscapes as repositories of stable layers
of historical meaning, which needed to be preserved so that the past could be
interpreted and recovered.[20] For many people, such landscapes are sacrosanct because they provide a
visible link back to a perceived golden age, implicitly even to the garden of
Eden, a sign of the common human nostalgia for a seemingly idyllic past.[21] While some commentators have fumed against this view of nature and
history as simplistic sentimentality,[22] their views have found no traction in public opinion. The most valued
historic designed landscapes are those that appear to offer constancy, which
have been maintained always to reflect the static vision of what is believed to
be the designer’s original intent.[23] Thus possible modern environmental improvements in and around historic designed
landscapes (such as rainwater storage systems to replace the use of potable
water in plant irrigation, flood defences to protect vulnerable landscapes, and
wind turbines to generate the power necessary to manage the land) are viewed as
visually intrusive, inappropriate, unsympathetic, and ultimately threatening.[24]
These concerns also reflect another conflict within the field of landscape design, which pits art against science or, rather more specifically, traditional aesthetic design against the practicalities of ecology. As explained above, many landscape designers have seen their role as essentially that of an artist, creating iconic, visually beautiful landscapes that are preserved and imitated over the centuries. It is easy to see how this view can conflict with any idea of the landscape designer as a manager of functioning ecological systems, having a principle focus on energy conservation, practical activities and problem solving. Why should an artist – or the preservation of the work of an artist – be constrained by the science of climate change and the humdrum realities of biological processes?[25]
But things must change. Although there has been very little research on the potential negative impacts of climate change on the cultural heritage,[26] it is already clear that historic designed landscapes are both past culprits and future victims of unsustainable practices. Climatic threats to historic English landscapes have been identified as the complete destruction of gardens through coastal retreat; loss of character as a result of the unsustainability of particular trees and planting schemes; extensive browning of parkland; subsidence, settlement and cracking of architectural features; difficulties in maintaining ornamental lakes and local water supplies; erosion and run-off. Plant material is particularly at risk, through wind damage, temperature changes, new pests and diseases, summer drought and winter flooding, problems in propagating native species that need cold to germinate, and complex changes in soil fertility levels.[27] Most solutions currently identified do not address the fundamental issue that we have designed and are trying to preserve unsustainable landscapes. Instead, they propose simply redoubling current, unsustainable interventions: the use of more potable water to irrigate parched lawns and exotic plants, for example, or the increased application of chemicals to deter new pests and diseases.
Yet there is some good news. New
values are emerging, which challenge the idea of preserving a historic designed
landscape as it was at a particular point in the past. This new way of thinking
rejects the obsessive, unsustainable restoration of original details, recognising
this as an ultimately unattainable quest for an accurate historical picture.
Among landscape professionals, if not yet the wider public, we can discern an
increasing acceptance that the authentic reproduction of historic landscapes is
simply not possible: any restoration will always be a modern-day
interpretation, even when seemingly blindly copied from original plans.[28] In the same way, Swedish
archaeologist Cornelius Holtorf argues that the remains of ancient objects and
cultural sites will always be viewed and interpreted through the context of
contemporary life and given present-day meanings specific to the culture and
experiences of the viewer: they have no inherent authenticity or “pastness.”
Indeed, the modern-day interpretation is all that matters: it is almost
irrelevant whether the original artifact is preserved or not. In the public
understanding of history, the interpretation of archaeological monuments takes
its place alongside other parts of popular culture such as Hollywood films like
Ben Hur or the theme parks of
This focus on interpretation and
experience over physical preservation may become increasingly important. Some experts stress that, given the threats
of climate change, it will be unfeasible to preserve all historic designed
landscapes, or to try to preserve anything forever[30] – and that some (maybe many) important landscapes will need to be
documented and then abandoned.[31]
Thus, instead of preventing change,
conservation is starting to be seen as assisting the management of inevitable
change. Cultural history is a continuing story, and its diverse, significant
elements might be retained and celebrated through time. Such a change in values
will allow us to acknowledge all the history in a site, including tomorrow’s.[32] It is an acceptance of a more individual, complex view of landscapes,
as eloquently described by the American writer Lucy Lippard: “Place is
latitudinal and longitudinal within the map of a person's life. It is temporal
and spatial, personal and political. A layered location replete with human
histories and memories, place has width as well as depth. It is about
connections, what surrounds it, what formed it, what happened there, what will
happen there.”[33]
Designers are thus to be involved
less in erasing evidence of subsequent human activity on a historic designed
site, and more in embracing that evidence, and indeed in adding further layers
that will provide value for future generations.[34] The Duisburg-Nord park and the Fresh Kills landfill, both mentioned
above, are post-industrial examples. In the traditional heritage field,
however, it is an idea more common in theory as yet than in actual practice,
but there are examples emerging: the
This shift, from preservation to
continuity, is not to destroy or dismiss the importance of historic designed
landscapes. It is to value them differently. The architect Juhani Pallasmaa
rightly described landscapes and buildings as "the most important external
manifestations of who and what we are ... transforming chaos into cosmos...
making the course of time visible; stimulating imagination of the future."[35] It is that link to the present and future that landscape designers and
historians need better to forge for historic designed landscapes. The public
must be helped to experience them in the same way that influential humanistic
geographer Yi-Fu Tuan urges us to see museums – places which “preserve
materials that mark the stages of confident growth and point to the future.”[36]
In any event, the emerging
conservationist view of history as a continuum must be good news for
sustainability. It should in theory allow us to include within historic
designed landscapes clear evidence of the early twenty-first century shift in
values towards environmental protection and sustainability. We might yet see
and learn to celebrate solar panels, greywater harvesting and reuse, on-site composting,
native meadows and green roofs placed centre stage at some of our iconic
historic designed landscapes.
But to succeed, I would argue that
we need a new intellectual framework and radically different, collaborative
action at a number of levels. First, landscape designers and historians need to
accept that they must work as part of cross-disciplinary teams – crucially
including climate scientists, environmental experts and ecologists, not as
occasional advisors but as equal partners – so that changes to heritage
landscapes really restore and sustain, rather than simply appearing to do so.[37] We need to move away from that tension between art and science, and
accept that to manage historic designed landscapes sustainably requires both
broad aesthetic judgments and detailed technical expertise. One cannot be
allowed to trump the other, even for our most cherished and important
landscapes.
Secondly, we need to redirect our
design and conservation practices by forging a new, more collaborative relationship
with nature, no longer seeing it as something static, visual and separate that
we can manipulate at will. Rather we must recognize, as argued by Aldo Leopold
and others, that humanity is simply a part of nature, and so our human
communities fundamentally include the non-human elements that Leopold
collectively called ‘the land’: waters, soils, plants and animals. Certainly,
given today’s looming climatic and ecological challenges, we need to accept
nature “as a dynamic, changing, and exchanging force field of ecological
process in which humans are actively immersed and engaged.”[38]
Finally, and perhaps most
dramatically, designers and historians need to work with the public to
reappraise why and how people value landscapes, what character and feeling they
convey, what they say about our relationship with nature.[39] We need fundamentally to re-write landscape design history, and to
rediscover the essential purpose and intent of designs, not simply to fixate
upon their initial appearance. There is a continuum of meaning and value over
the centuries that is today frequently only glimpsed. As Anne Whiston Spirn has
urged, we need to rediscover the deep context underlying the surface of
landscapes, to explore their settlement patterns, geological features, and the
cultures and attitudes that have shaped them.[40]
Such change cannot happen overnight.
It will certainly, as Carleton B. Christensen argues in a different context,[41] require new national and international guidelines to support and
encourage the sustainable management of historic designed landscapes. But,
despite Christensen’s views, I would argue that we cannot simply wait for such
formal frameworks. They will only emerge slowly, and at first, be tentative and
much diluted by a desire to find consensus. While we wait for such top-down
direction, we need to start pilot projects or demonstrations now: to encourage
and sponsor local experimentation – a sustained civic exchange – with people
considering their own local special places and how they can be adapted. People
need to see, experience and experiment before they can accept the radical
changes that will be necessary.[42] I am not arguing for the stultifying public consultations of today
which so often produce lowest common denominator results, which everybody
accepts but nobody loves. Rather we need to look to successful models such as
the so-called RSVP cycles of community involvement orchestrated by designer
Lawrence Halprin, which replaced goal-driven designs for landscapes with an
enduring creative process that allowed for continuing change and growth.[43]
Similarly there is much merit in the
approach advocated by Bill Jordan,[44] who seeks to reclaim and reinstate native habitats through ritual and
communal human intervention, with the fundamental focus on getting processes to
work – rather than the traditional method of using an expert to produce a
seemingly complete end-product.
Another promising model is the
continuous productive urban landscapes (CPULS) concept of André Viljoen and
Katrin Bohn, which aims to bring together diverse experts, local leaders and
community groups to create sustainable farms within cities.[45] It has been successfully piloted in the north of
Involving both the scientific
community and members of the public in pilot sustainability projects at
historic designed landscapes is not to reject the importance of historical
values or aesthetics. Nor is it recommending that humanity should be prevented
from any apparent design interventions. Far from seeking to impose the
equivalent of an ecological hair shirt on historic landscapes, active
considerations of sustainability in a historic context should allow us to
enjoy, design and value the landscape anew, as something joyous, sensuous,
intimate, and profoundly relevant.[46] Such an approach is evocatively described by Native American writer N.
Scott Momaday:
Once in his life a man ought to concentrate his
mind upon the remembered earth, I believe. He ought to give himself up to a
particular landscape in his experience, to look at it from as many angles as he
can, to wonder about it, to dwell upon it. He ought to imagine that he touches
it with his hands at every season and listens to the sounds that are made upon
it. He ought to imagine the creatures there and all the faintest motions of the
wind. He ought to recollect the glare of noon and all the colors of the dawn
and dusk.[47]
Working collaboratively, with scientists, with
natural systems and with the public, designers and historians can bring about a
fundamental shift in our relationships with historic designed landscapes: away
from managing them as a static image of visual beauty and towards embracing
them as a dynamic, evolving part of human culture, celebrating the vibrancy of
history and looking forward to a sustainable future. Our cherished landscapes
have the capacity to “become a ritual space for the human community to
reestablish its ancient performative connection with the land.” We must act. By
putting sustainability at the heart of landscape design history, we can find
the way to a modern kind of
Jill Sinclair is a British landscape
historian and author. Trained in landscape design history at Harvard, she now
lives and works in
[1] Carl Smith, Nigel Dunnett and Andy
Clayden, Residential Landscape
Sustainability,
[2]
American Society of Landscape Architects, Lady Bird Johnson Wildflower Center,
University of Texas at Austin, United States Botanic Garden, The Sustainable Sites Initiative: Standards and Guidelines, Preliminary
Report 2007,
http://www.sustainablesites.org/report.html, and Smith, Dunnett and Clayden, Residential Landscape Sustainability,
pp. 79-81, 110-112.
[3]
Neil Evernden, ‘The Social Use of Nature’ and ‘Nature and Norm’ in The Social Creation of Nature,
[4]
John Passmore, Man’s Responsibility for
Nature,
[5]
Tiiu Poldma, ‘Dwelling Futures and Lived Experiences: transforming interior
spaces’ Design Philosophy Papers 2
/2008, www.desphilosophy.com/dpp/dpp_journal/cited_papers/paper3_poldma/
html.
[6]
Brenda Brown, ‘Holding Moving Landscapes’
Landscape Journal 17:2, 1998. p. 64.
[7]
Robert Smithson, ‘Cultural Confinement’ in The
Writings of Robert Smithson, ed. Nancy Holt,
[8] Marc Treib, ‘Must Landscapes Mean?
Approaches to Significance in Recent Landscape Architecture’ in Theory in Landscape Architecture: A Reader,
ed. Simon Swaffield, University of
[9]
Catherine Howett, ‘Systems, Signs, and Sensibilities’ in Theory
in Landscape Architecture, ed. Swaffield, pp.108-116.
[10] Smithson, ‘Cultural Confinement’ op cit.
[11] See for instance B. Matilsky, Fragile Ecologies: Contemporary Artists Interpretations and Solutions, New York: Rizzoli International Publications, 1992; Landscape Journal, Eco-Revelatory Design: Nature Constructed/Nature Revealed, special edition 17:2, 1998; G. Kester (ed.), Groundworks: Environmental Collaboration in Contemporary Art, Pittsburgh, PA: the Regina Gouger Miller Gallery, Carnegie Mellon University, 2005.
[12] Joan Iverson Nassauer, ‘Messy Ecosystems, Orderly Frames’ in Theory in Landscape Architecture, ed. Swaffield, pp. 196-206.
[13] Susan M. Galatowitsch, ‘Ecological Design for Environmental Problem Solving’ Landscape Journal 17:2, 1998, pp. 99-108.
[14] Intergovernmental Panel on Climate Change, ‘Summary for Policymakers. Climate Change 2007: Impacts, Adaptation and Vulnerability’ in Fourth Assessment Report of the Intergovernmental Panel on Climate Change, ed. M.L. Parry et al. Cambridge University Press, 2007, pp. 7-22.
[15] Smith, Dunnett and Clayden, Residential Landscape Sustainability,
pp. 79-81, 110-112.
[16] Tony Fry, ‘Elimination by design’ Design Philosophy Papers, 4/2003 www.desphilosophy.com/dpp/dpp_journal/cited_papers/debate_elimination/ html.
[17] National Park Service, ‘Guidelines for Reconstructing Cultural Landscapes: Special Considerations’ Secretary of the Interior’s Standards for the Treatment of Historic Properties and the Guidelines for the Treatment of Cultural Landscapes, http://www.nps.gov/history/hps/hli/landscape_guidelines/reconstruct/special.htm.
[18] American Society of Landscape Architects, Lady Bird Johnson Wildflower Center, University of Texas at Austin, United States Botanic Garden, The Sustainable Sites Initiative: Guidelines And Performance Benchmarks, Draft 2008, p. 107.
[19]
Richard Haag, ‘Eco-Revelatory Design: The Challenge of the Exhibit’ Landscape Journal 17:2, 1998, p. 72.
[20] Stephen Daniels and Denis Cosgrove,
‘Introduction: iconography and landscape’ in The Iconography of Landscape: Essays on the Symbolic Representation,
Design and Use of Past Environments, ed. Denis Cosgrove and Stephen
Daniels, Cambridge University Press, 1989, pp. 1-10.
[21]
Yi-Fu Tuan, Space and Place: The
Perspective of Experience, University of
[22]
Earthworks artist Robert Smithson, for instance, condemned the idea of “Memory traces of
tranquil gardens as 'ideal nature' – jejune
[23] Louise A. Mozingo, ‘The Aesthetics of Ecological Design: Seeing Science as Culture’ Landscape Journal 16:1, Spring 1997, pp. 46-60.
[24]
English Heritage, Climate Change and the
Historic Environment,
[25] Mozingo, ‘Aesthetics of Ecological Design’.
[26] Cristina Sabbioni et al, ‘Global
climate change impact on built heritage and cultural landscapes’ in Heritage, Weathering and Conservation,
ed. R. Fort et al., Taylor & Francis/Balkema, 2006, pp. 395-401.
[27]
Richard Bisgrove and Paul Hadley, Gardening
in the Global Greenhouse: The Impacts of Climate Change on Gardens in the
[28]
Kim Wilkie, ‘The Uses and Abuses of History’ (lecture given in the Vista series
of debates at The Museum of Garden History in
[29]
Cornelius J. Holtorf, From Stonehenge to
[30] Cassar, Climate Change and the Historic Environment.
[31]
Just as Shakespeare in his Fair Youth sonnets recognised the impossibility of
preserving beauty against the “wrackful siege of battering days” - except as
descriptions in his poetry.
[32]
English Heritage, ‘Constructive Conservation’
http://www.english-heritage.org.uk/server/show/nav.19808.
[33]
Lucy Lippard, The Lure of the Local:
Senses of Place in a Multicentered Society,
[34]
English Heritage, Conservation
Principles, Policies And Guidance For The Sustainable Management Of The
Historic Environment,
[35] Alan Tate, ‘Spatial Recall: The Place of Memory in Architecture and Landscape’ Landscape Journal 26:2, 2007, p. 328.
[36]
Yi-Fu Tuan, Space and Place, 195. See
also Tim Ingold, ‘The Temporality of the Landscape’ in The Perception of the Environment,
[37]
Galatowitsch, ‘Ecological Design’.
[38]
Catherine Howett, ‘Ecological Values In Twentieth-Century Landscape Design: A
History And Hermeneutics’ Landscape
Journal 17:2, p. 1998, p. 84.
[39]
Howett, ‘Ecological Values’ p. 80.
[40]
Anne Whiston Spirn, The Language of
Landscape,
[41]
Carleton B. Christensen, ‘Redirecting Affective Dispositions: how philosophy
can contribute to eco-political thinking’ Design
Philosophy Papers (2/2008). www.desphilosophy.com/dpp/dpp_journal/cited_papers/paper1_ChristensenAffectDis.html.
[42] Robert Thayer, ‘Gray World, Green Heart’ in Theory in Landscape Architecture, ed. Swaffield, p. 189.
[43] Lawrence Halprin, ‘The RSVP Cycles’ in Theory in Landscape Architecture, ed. Swaffield, pp. 43-48.
[44] William R. Jordan III, The
[45] André Viljoen, ed., Continuous Productive Urban Landscapes CPULs: The urban agriculture design book for sustainable cities, Architectural Press, 2005.
[46] Mozingo, ‘Aesthetics of Ecological Design’.
[47]
[48]
Frederick Turner, ‘A Cracked Case’ Landscape
Journal 17:2, 1998, p. 135.