A problem, or an opportunity for a new landscape paradigm?
I was recently working on a tree project in Abu Dhabi when I came across a derelict site which intrigued me with it’s range of exotic self-seeded, non-native plants. The site was next to the Corniche and sandwiched between the Formal Park, my hotel and Capital Gardens. It struck me initially as the perfect basis of a xeriscape, as all the plants (mostly trees) were thriving without irrigation. On closer inspection and identification of the species involved, things got more complex and raised a lot of potentially conflicting thoughts and issues.
A natural Xeriscape
The site was clearly awaiting redevelopment and the plant invasion was opportunistic. Nothing that I could identify was native, yet all seemed happy there. When you see the list, you might understand why. Amongst the plastic and litter I identified:
- Prosopis juliflora
- Ficus benghalensis
- Eucalyptus glaucescens
- Conocarpus lancifolius
- Washingtonia robusta
Of those plants, the P. juliflora was the most robust and when you look at its reputation, that is of no surprise. It was of landscape scale, lush and greener than anything in the adjacent parks. It’s form, leaf, flowers and seeds are attractive from a landscape perspective. Yet this is undoubtedly the most controversial plant on this list – some would say alarming. A Native of arid zones in central and South America, this was, like so many others, introduced into the UAE in the 70’s as a forestry plant. Lauded as something of a super-crop tree, it is tenacious, vigorous, provids fuelwood and stock-feed in the form of abundant seeds. The latter, it turned out, were a problem in that they are spread by cattle and are extremely aggressive. Plants also regenerate rapidly from the roots when cut back and they reputedly produce biochemical inhibitors to suppress competition (allelopathy). With no natural competitors in the UAE and roots that can descend 50m in search of water, they out-compete native flora, even their cousin, Prosopis cineraria (ghaf tree).
Prosopis juliflora flowers
P. juliflora has a low, mounding habit, attractive from a landscape point of view.
Also on the site were a number of Banyan trees, Ficus benghalensis, which seemed to be growing happily. Another tough survivor, it should be borne in mind that the water table here is likely only a metre or so below ground, although it will have a high saline content.
Then there was Eucalyptus glaucescens, another forestry/amenity introduction of the 70’s, also known and now generally avoided for its aggressive roots, yet here looking beautiful with its grey, lanceolate foliage. This was the tallest tree on site.
Eucalyptus glaucescens, showing adult foliage
Of course, there was the ubiquitous Conocarpus lancifolius, widely planted still yet also recognised and a danger to any nearby drains, and on it’s way out in popular use. Except it does make such a good tall hedge, and it has a much nearer native origin, coming from Somalia, Djibouti and Yemen. I’m not sure that the UAE landscape industry is ready to ditch it just yet.
There was even a palm, Washingtonia robusta, self-seeded around the place. Much of it was to be found growing underneath the canopy of the P. juliflora, so that at least is not put off by any allelopathic biochemicals from the Prosopis.
I believe this legume is Sesbania sesban, more commonly seen with yellow flowers. Rose-ringed Parakeet
Inhabiting, or at least visiting the site, was a Rose-winged Parakeet. Another exotic invasive with beautiful form but aggressive tendencies; it seemed appropriate to the moment, somehow.
What does this mean for future landscapes and ecology?
From a conventional ecology point of view, these plants are all threats, and the threats probably outweigh their usefulness. So why am I even talking about this? Clearly, the move towards more naturalistic landscapes draws heavily on native species and would shun all of these species.
Except we have climate change.
Climate change is the elephant in the room, when it comes to ecology, in fact when it comes to sustainability generally and a livable planet overall. That we have already moved beyond vital tipping points is highly likely; that climate zones are moving away from the equator at a rate too fast for nature to adapt is a fact. Flora and even some fauna just can’t move regions that quickly. They will adapt, eventually; but those that are rare, specialist and struggle with change, will die. The tougher generalists will adapt and survive. Nature will build a new ecology to reflect the new reality, and it doesn’t mind if it takes a few thousand years to do so. Only we humans mind and so, if we are to survive, we must adapt our environments to fit the new reality. It is a sad fact that many cherished plants will eventually die out or move zones. In the UK, I dread losing our native oaks (I view these as our ghaf tree equivalent), yet we may get Mediterranean species to replace them, such as holm and cork oak.
If you are already positioned in the arid equatorial zones then you have precious few plants that will form your new ecologies and landscapes. Perhaps the plants I have described above will be UAE naturalized-natives in 100 years’ time and the ghaf and sidr may be gone, or diminished, or moved north. I hope not, but before we spend vast fortunes on eradication and control of non-natives, we should look to the future. These aggressive invaders may just form the landscape of our children; I know I’d rather live with a landscape, than none at all. If there is no landscape, there is no life. They may, in fact, be here to save us.
Once we grasp this fact, we can look at building new landscapes to suit our changing environments. I’ve written about this before and you can read the articles listed below. We must be vastly more holistic in our thinking in order to do this and broaden our horizons to understand the new future. Technology will help us to monitor, collect data and produce working strategies. Robotics and drones will help manage and control plant communities. Alongside that, we need a vastly better understanding of soils, microflora and fauna, for the bit of nature that we see is just, literally, the tip of the iceberg. The selection of tree and shrub species for adaptation is easy, we get this wrong when we don’t deal in whole context thinking eg. only thinking of forestry or ornamental benefits.
The challenge ahead is huge but in a weird way, exciting; it will challenge the human race to grow. There’s a whole new science to develop and we’d best get on with it.
Other articles by ML that relate to this topic:
Posted in Arboriculture, Climate Change, Dubai, UAE, Ecosystem Services, Environment, landscapes, Middle-East, Natural Landscapes, Regenerative Planting, Sustainability, Trees Tagged with: Abu Dhabi, adaptive landscapes, biodiversity, climate change, Dubai, ecology, Invasive species, landscape, Middle-East, native plants, non-native, sustainability, trans-migrational landscapes, trees, wildlife
This review first appeared in Thinking Gardens in February 2016.
This book represents a new wave of thinking about “natural” planting that has been emerging in recent years; actually it has been developing for the last thirty or more years but like all new things, they tend to follow an exponential growth curve. I’d say that right now we’re near the base of the steep upward bit with this one. Left unchecked, exponential growth tends to end in collapse but this idea deserves to stay the course. To do that it has to translate from a style into a design language and that’s what this book is really about.
This is a very US-centric book, unsurprising since Thomas Rainer is from Alabama and Claudia West, though of East German origin, lives in the US. I would have liked her influence to have given the book a more European feel; it would have been richer for it and more globally relevant.
The book has already been reviewed on TG by James Golden but although I’ve read this I’m not referring to it, save for one point. Needless to say, that review is also very US-centric; my purpose is to give a more UK/European viewpoint.
The thinking in this book is very design-led, in which the authors refer to landscape archetypes, which I think is very useful. However, they only select three – grasslands, wood and shrubland and forest. Given the vastness and variety of American climate types (which has just about everything), I’m surprised they didn’t mention desert landscapes, arid-mountainous or Mediterranean (as in Californian coastal regions); I suspect they have simply not worked with these climates, yet to omit them from a listing of archetypes is limiting. It is clear too, that their interest lies mostly in the grassland or prairie archetype.
There are many archetypes other than the three mentioned in this book. Desert near Dubai, UAE.
Referring back to the JG review, he wanted to add another archetype, Edges. I would argue that the wood and shrubland archetype is an edge, or rather a transition. Only in farmer’s fields do we have an edge as such. I would think of these archetypes as parts of a sine wave, one transitioning into another as climate and topography dictate. This sine wave also rolls around the globe over time, one archetype superseding another in any given place. Remember that the Sahara desert was woodland just 10,000 years ago, when we emerged from the last ice-age. This fits with the theory that there is no such thing as an ecological climax.
Another interesting thing to come out of this book is the idea of “designed plant communities”. You could say that any grouping of plants together is a designed community but the context they use of grouping plants by habitat-type rather than just their visual look is refreshing. This makes good sense, provided that such a designed grouping is appropriate within its wider environmental context. Taken to its logical extreme, however, you end up with native plants only.
What may be harder to work out is how much of this philosophy fits into a garden. Even the largest garden can’t fit in a whole wood, let alone a prairie, so of course, we must work by inference. This aspect of things is not really discussed in the book and most of the pictures are of large gardens in amazing settings; domains of the lucky few who we landscape designers occasionally get to work for. Yet for the majority of small garden owners, instruction for the adaptation of these principles is missing.
The Lurie Garden, Millennium Park, Chicago by Piet Oudolf exemplifies modern Naturalistic planting. This is large ribbons or drifts of plants rather than the species intermingling favoured in this book
The same garden in November; form is held in the stems and shapes of the seedheads but use of some woody plants might add more winter form?
I feel that the book only really looks at one archetype, that of New Perennial/Prairie style gardens and there is a big focus on this at the moment. I might compare this book with Oudolf & Kingsburys “Planting, a New Perspective”. That book, whilst not getting down to the archetypal design level, is more European in focus, so possibly a good companion read. Yet it too, mostly deals with perennial-based planting, as you would expect from these gents. The work of Nigel Dunnett and James Hitchmough comes to mind too. The fast-changing essence of many of the plant species used means that these perennial plantings are subject to rapid change, even degradation, over time as some of the most desirable and favourite species are so short-lived (Achillea and Echinacea for example).
I think the Wood and Shrubland archetype is the most likely to resonate with those seeking to create a garden, yet the ones of great importance to me, in a European and specifically coastal Southern England context, is that of the unmentioned Mediterranean or Arid-Mountainous archetypes. Whilst some areas of the Mediterranean clearly fit the Wood & Shrubland archetype (ie broadleaf and evergreen woodlands and Maquis), others such as Garigue, Salt Marshes and Rocky Shorelines, do not. I think this range and essence adds up to its own unique archetype. Arid-Mountainous too is quite distinct (although again with areas that fall into the realm of other archetypes), yet gives us wonderful, tough plants like Perovskia. The Dutch biologist Brian Kabbes has done much to inspire and educate us with his exploration of plants in Kyrgyzstan.
Perovskia arbrotanoides growing wild in the mountains of Kyrgyzstan. Photo by Brian Kabbes
To me, one of the biggest drivers in creating naturalistic planting communities has always been about resilience. To my mind, planting should survive without irrigation, so low water-use plants are attractive. I can’t think of a single garden in the UK that couldn’t survive without irrigation, the desire to use pop-up sprinklers is ridiculous and surely industry-driven. Climate is changing now beyond speeds that Nature can shift plants and ecologies around the globe, so it is something we humans must do if we want a future landscape of any description (oh, and for our own survival). So we have to transmigrate landscapes from one continent to another to keep pace; yes, with all the risks that entails when introducing new species (and it would not be just plants we’d have to relocate). So learning about plant communities and how to build them is a vital skill which this book begins to explore, yet could have gone much further in instructing us on.
This coastal garden I designed in Southern UK loosely mimics the Mediterranean archetype, and uses a full range of grasses, perennials, sub-shrubs, herbs, shrubs and trees.
In the European context then, archetypes other than grassland/prairie might be more useful and translatable into a garden context. That this book has not covered these is not really surprising but it is a mistake to think that the new language of resilient/natural/sustainable landscapes is dominated by perennials and grasses. This aspect is possibly a trend within the underlying drive for a natural interpretation.
A European version of this book is needed, which could perhaps take it to the next level of design language development. In this respect, inspiration can be drawn from another book, “A Pattern Language” by Christopher Alexander, which although about architecture and space, is also about soul, spirit, context and community, realised through the use of a language of patterns. In a very real way, “Planting in a Post-Wild World” attempts to create an archetype-based design language and is a valuable contribution to that. We just need the language to be global, or to see this book as a regionalised attempt to cross boundaries and develop new thinking.
This is an important book and I recommend it; for all its limitations it shows the way to develop landscapes that are truly new and profound.
Posted in Book Review, Design, Environment, landscapes, Natural Landscapes, Regenerative Planting Tagged with: adaptive landscapes, book review, ecological landscapes, ecology, gardens, landscape, natural planting, sustainability, trans-migrational landscapes
Almost all urban landscapes are contrived and designed, due to their artificial nature and short timescales of development and use. We see increasing use of mature rootballed trees and extensive hard landscape and this is normal for intense inner urban areas; I do get concerned that the increasing complexity of urban planting systems divorce trees particularly from their natural functions and prevent the occurrence of the biological interactions/communities that go to make up an ecosystem. For example, I have seen trees planted whose surface levels are around a metre below the surrounding paving level. No matter how well designed, this seems fundamentally wrong to me.
So I’m thinking that there must be a way of dealing with the majority of less intense landscape zones (especially where there isn’t the financial budget that a high-end development attracts) to provide urban regeneration, ecological restoration and biophilic connection, all on a modest budget. This would create a new method to allow for wide-spread adoption in urban and suburban zones. I think the solution comes from Nature’s own process of natural regeneration and a developed philosophy of minimal (but specific) preparation.
silver birch are pioneering species for natural regeneration
Starting from the observation that Nature is very efficient at regenerating itself, what can we do? Too often, I have seen unnecessary interference in this process. I still recall that a few years after the great storm of 1987, I walked through some nearby National Trust woodland of pines and birch. A great deal of damage had been done with many trees blown over. Birch had however, regrown abundantly from dormant seed and was already three or four foot tall. The NT then sent in the bulldozers to clear out the fallen wood so the area could be – replanted. I watched them tracking over all the natural regeneration. Why didn’t they just leave well alone? The restoration of the woodland was only slowed down by such clumsy interference and this was not even a productive forest.
If we simply broke up paving in our urban centres and loosened up the sub-base, what would happen? Nature would soon find a footing and things would start to grow; however, that process would be too slow and unpredictable for human sensibilities. So what if we did a little more, adding a small amount of topsoil to the rubble, planting small (1+1 year transplants) bare root trees and shrubs, with plugs of understory forbs, ferns and grasses. Starting so young, we’d generate a successful community in no time. These could be designed as narrow ribbons – two to four metres wide, inserted into suitable wider areas of paving.
An urban area suitable for natural regeneration
The above area was one I thought would be suitable for such an approach; there are many such areas throughout all urban spaces. They cry out for regeneration, yet seldom can this be done for lack of adequate finance. Below is a quick sketch showing how it might look.
Sketch showing regenerative planting
The benefits of such an approach would be huge. It would cost far less than using a traditional approach to landscaping such an area, maybe half (I haven’t costed it!). The care would move from maintenance to management, using a rotational coppice methodology, rather than trim and tidy (which always ruins a plants natural habit. Biodiversity would be hugely enhanced, air pollution mitigation would increase, wind buffering, urban heat island reduction, stormwater runoff (they would act as rain gardens) and of course, our biophilic needs, our connection to nature.
Someone needs to be bold and try it; talk to me…
Posted in Arboriculture, Biophilia, Climate Change, Design, Ecosystem Services, Environment, landscapes, Regenerative Planting, Trees Tagged with: adaptive landscapes, biodiversity, biophilia, eco-system services, ecology, garden, gardens, landscape, native plants, pm10, pollution entrapment, rain gardens, sustainability, sustainable, trans-migrational landscapes, trees, urban greening, urban heat island, wildlife
I’ve written before on the subject of adaptive landscapes and trans-migrational landscapes but I’ve been reading recently of a real-life ecology that was created by man in the last 200 years, and is thriving. This is on Ascension Island in the South Atlantic Ocean, a once barren volcanic rock, which is now a thriving cloud forest, created in a somewhat uncoordinated way by successive generations of British sailors and governors bringing plants from all over the world. Where there were once just 25 species, there are now over 200, as this article tells.
Non-native bamboo and moss create homes for native ferns. photo Fred Pearce.
Whilst this example may be a one-off, it is nonetheless a hopeful sign. If new and thriving ecologies can be created with little real thought and science, it gives hope for what we can do if we put our minds to it.
In my previous articles mentioned above, I outlined the reasons why this is necessary. To recap, it is due to the planetary changes that are now occurring, whose effects we have yet to fully experience, which is going to change this planet for millennia to come, even if we get a grip on carbon emissions, which we must of course do. If we don’t, runaway climate change could make this planet largely uninhabitable (at least to higher life forms). Ecologist have to radically re-think what they consider to be ecology, for Nature cannot adapt the landscape at the rate of our man-induced changes. That means that species cannot adapt and move with the shifting geological region of the climate zone they are used to. Zones are moving North and South, away from the equator at a rate which may change 20% of the world’s climate zones by the end of the century.
Of course, Nature will correct things given time, but mankind cannot afford to wait, if it wants a planet worth living on – and the ability to live on it. That’s why the Ascension Island story is such good news. I would dare bet that we could extensively re-vegetate (or terraform, to use a word found in science fiction stories) areas within a 50 year period if we turned our minds to it, and our political will.
Ironically, I can see some of the stiffest opposition to this coming from conservationists. Much is made of the negative effects of the global migration of plants and insects, but we have to balance that with the positive gains, which are seldom mentioned, yet so taken for granted. And the planet is going to change now, whether we want it to or not. I’d rather the UK (for example) had a Mediterranean flora and fauna than none at all. We may one day grieve the loss of our native oaks, finally unable to cope with the higher temperatures, but we would surely welcome the holm oak (already naturalising in the South coast area), cork oak and olive here. Having an ecology of beauty and abundance is what counts now, not preserving what we are used to having. Get used to that; it’s already too late.
But new adaptive ecologies, created by transferring plants, insects and microbes from other similar zones in the world, would give us a new practice, that of trans-migrating landscapes, and a new science, a new understanding. In this we must learn not to manipulate, but to understand Nature, to assist in what she would herself do, but over millennea. And we must do it within a lifetime.
Best get started…
Posted in Climate Change, Environment, landscapes, Sustainability Tagged with: adaptive landscapes, climate change, ecology, sustainability, trans-migrational landscapes
I’ve been doing a lot of research since writing my blog post on trans-migrational landscapes, my theory on how we have to adapt our natural environments – or rather, help them adapt – to combat the rapidly increasing effects of climate change. It’s not going to be easy; right now I’m not sure if we can do it without making a complete fudge of things, or if we would simply be making matters worse. I’ve just read this article in the Telegraph, which would seem to agree with my idea, but as some of the comments after point out, it’s the insect and microbial ecologies that count; many of our native population just can’t live on non-native plants.
I’m also reading a book by ecologist Douglas Tallamy, called Bringing Nature Home; in which he talks eloquently about these problems, about the environmental collateral-damage caused by horticulture and agriculture. That plants, insect and fungi go rogue is understood; that they might only do so after 80+ years of benign cultivation and growth in a new continent is astonishing. Alien plants displace more fragile natives and they can rampage, simply because they are not subject to the checks and balances caused by a predatory ecology. What we, as gardeners, admire about an introduced plant – that it doesn’t get eaten by “pests” – shows that it is ecologically barren, is not taking part in the local micro-ecology and so is not being transformed into higher trophic levels of being, ie. into the higher food chain of insects, birds and mammals.
So if, as Tony Russell suggests in his Telegraph article, we were to plant non-native woodlands, they would become ecologically less diverse as a result, even if the trees were better able to grow in an altered climate. So should we then introduce all or some of the microbes and insects that naturally live in such trees? That could be very dangerous, with results that are entirely unforeseeable. Of course, we might have to gamble as the climate gets more and more extreme and moving Mediterranean ecologies to Southern England might save them as they die out in the place where they have evolved to live in.
My fear is that we are not smart enough to understand and control (as if we ever could) such a process, my hope is that we could take the issue seriously enough to learn how to do this successfully. We will need it, if we are to retain useful and beautiful ecologies on which we depend for our survival. Nature doesn’t need it, because she won’t mind taking a long, LONG, time to rebuild things…
Posted in Environment, landscapes, Sustainability Tagged with: climate change, gardens, landscape, native plants, trans-migrational landscapes, trees
With the climate shifting now so rapidly that we cannot foresee what the future may bring – or rather, with an ever increasing certainty of life as we know it struggling to survive – do we need a new approach to our understanding and management of our natural landscapes? I think this will become inevitable and that this idea needs to become a proactive rather than reactive measure.
A quick look around the globe shows Arctic ice melting at unprecedented rates, massive flooding events (in Bangladesh recently 20m people were displaced), increased hurricanes (h. Sandy), both in frequency and strength, desertification through deforestation and inappropriate agriculture and relentlessly increasing global temperatures, to name just a few that come to mind. And we can see effects much closer to home. The UK is likely to lose most or all of its ash trees due to the fungus Chalara fraxinea, which has mutated and migrated from Japan, where it is a balanced part of its ecosystem. Ash trees make up 40% of the UK landscape canopy. This follow from our lose of elms, but oaks have their problems too, as do horse chestnut and and larch, which although not native, are under attack from imported diseases. We have everywhere, a landscape under stress, that cannot adapt to the rapidly changing environments we humans have imposed upon the planet, either from our living patterns or from pollution. Our landscapes are under duress as never before. Vast and rapid change is inevitable and cannot now be stopped. But there is possibly something we can do, and that is learn to help speed up Nature’s adaptations. This would involve actively changing the flora and fauna of our native landscapes, an approach that would not be without risk, but might mean that some kind of meaningful ecology can adapt and survive.
It is clear that to do nothing is to watch our beloved regional and continental. landscapes change beyond recognition. But this would require a sea-change in thinking and current practices. Ecologists naturally resist the introduction of new species, with good cause; the aforementioned tree diseases are with us at least partly because of imported plants or timber. Lists of invasive species and control advice is provided in the UK by the Non native Species Secretariat; but I now think that we are beyond preventing the influx of invasive species and that we must look ahead and ask ourselves: do we want an ecology and landscape in 50 or 100 years time? Of course the answer is yes; we depend on our landscape, body and soul, and we may regret that we were forgetful of that for so long. But we cannot preserve what was, into the future.
My previous post was a review of a book by Bill McKibben, a leading environmental thinker, who says that we now live on a different planet, that it’s future will never be as its past was; he renames the planet Eaarth. We have caused this; if we are to adapt to our future, we have to re-think our attitudes and expectations. We cannot conserve England’s green and pleasant land; it is gone, or going. We must adapt it to suit its future, to build new ecologies, with new species or variants of existing species that are better able to cope. Ironically, trans-migrating species from one continent to another may save them from extinction in their original habitat.
This would be a big challenge; it is easy to introduce a new tree species, but it is the microflora and fauna that come with them that is important, for both the good and the bad. Sycamores are a now familiar part of the British landscape but are non-native and considered invasive. Whilst they are robust and may be well suited to our warmer climate, they are ecologically barren in the UK landscape, when compared to our oaks, which support some 300 + species of life. And this is the crucial bit; nature builds up complex and diverse ecosystems, of which we are still largely ignorant. Thus if we are to be able to do this with any success, we need to learn a new discipline, that of building micro and macro ecologies to suit our new future. If we put the same energy into this as we do GM research, it would be far more productive and useful – but it can’t be funded by private companies; this is our future, not a potential for financial gain.
And whilst we are at it, let’s build a new agriculture, based on perennial crops and trees, all as part of our ecological future. A diverse polyculture of trees, shrubs and herbs which provide a diversity of food, fuel and resources, including wildlife. Such an agriculture (or agroforestry, forest gardens, permaculture) will not be dependant upon fossil fuels, chemical fertilisers or pesticides as it’s perennial; harvesting can be done by hand or machine, and methane from cellulose digestion can provide the fuel for tractors where they are used. Nuts replace wheat and we move to a far more resilient and varied diet, which will make us healthier and give us food security, both of which are in rapid decline. Such annual crops as we do grow will be the domain more of the market-garden, a philosophy which we must revive to give us local food. Who knows, such balanced, wholesome and resilient landscapes might even be good for our soul’s too; certainly peace of mind relies on having a secure life, and we are rapidly losing that, far more than we realise.
So we need to build a new philosophy and practice of trans-migrating landscapes from areas of stress to areas of comfort, to match the shifting of climates zones around the world. It’s quite a challenge but we might just learn some humility and a far deeper appreciation of nature. In fact, we might just finally discover that we are inseparable…
Posted in Environment, landscapes Tagged with: ecology, landscape, microbial, native plants, sustainable, trans-migrational landscapes, trees