March 6th, 2017 by Mark Laurence

I’m pleased to have launched a new website and blog dedicated to this aspect of my work.  Over time the blog will become a useful resource to all those interested in the care of trees in the Middle-East.  My focus and experience has so far been within the UAE but the tree range is similar in most GCC countries.  treecare UAE

Posted in Arboriculture, Climate Change, Dubai, UAE, Environment, Middle-East, Trees, Urban Landscapes Tagged with: , , , , , ,

February 7th, 2017 by Mark Laurence

On my most recent trip to Dubai, I enjoyed walking through some of the new landscapes that emerge as projects are completed.  The UAE, along with most regions of the Middle-east has a rather limited palette of plants to work with (although that is growing as new plants are tried). What stuck me, however, was how poor the quality of nursery stock was in some cases and what problems are being created for later, especially with regards trees.

This is not new, nor confined to this part of the world but it bothers me that new areas of urban green are sometimes given a poor start with sub-standard nursery stock, often flown in from other parts of the world.

Simple pruning at an early stage would have improved this tree’s framework, removing crossing and rubbing branches.

Wandering around a residential area in Jumeirah, I came across some newly planted Delonix regia, one of my favourite exotic trees.  At first glance it looked nice, a simple planting of trees and groundcover but on closer inspection I was somewhat dismayed at the condition of the them.  The problems of poor framework were caused by their time in the nursery, not due to planting, although some of them could have been rectified by a vigilant planting crew.

This tree tie – complete with post – must have been like this from the nursery. The post did not reach the ground.

Many of the dozen or so trees had ties left on which the tree had grown around completely, making them impossible to remove.  As the planting is only around two years old (by my estimation), these may have been on the trees from their time in the nursery.  Possibly the planting was older and pre-dated the building they were attached to and the trees then grew around the ties after planting.  Either way, it’s a strong indication of neglect or lack of care. In the picture below, all the bark ridge above the tie may indicate “included bark” – bark sandwiched against bark, preventing live tissue growth and a strong branch collar formation.

The tree tie is trapped with “included bark” at the branch collar, which indicates a potentially weak branch join.

Several problems are arising here: pre-planting care in the form of correct formative pruning (five minutes with a pair of secateurs) and Post-planting care in terms of releasing planting ties – if they were not simply left over from the nursery days.  If there is no way to go back and release the ties, a bio-degradable tie should have been used.

This Ficus nigra was most likely damaged long before it was planted in this location.

Damage to the main trunk or structural framework of a tree might go unnoticed when the trees are small but cause major problems as the tree gets older and puts on size and weight.  This can range from the cosmetic to the potentially dangerous in a large tree and at this stage the remedy is costly and the expertise hard to find.

 

As fast-growing cities like Dubai mature, the needs of landscape shift from creation (in a hurry) to maintenance (at a constant pace).  Skills, awareness of the need for – and absence  – of skills, will become more and more urgent.  If Dubai wants to keep it’s beautiful, green mantle, then there is a whole new phase of arboricultural care awaiting to be discovered and initiated. I have carried out trees assesments and given basic training of correct pruning methods in the UAE, but that has hardly scratched the surface; there is a lot more to be done.

Trees are the urban, biophilic, blanket that clothe and surround the concrete mountains we build.  Trees make hot places not just bearable, but unbelievably beautiful.  Trees absorb dust, cool the air, add moisture and oxygen and enrich our Souls.  We need to honour and look after them, so that they can look after us.

Posted in Arboriculture, Biophilia, Climate Change, Dubai, UAE, Environment, landscapes, Middle-East, Trees, Urban Landscapes Tagged with: , , , , , , ,

July 10th, 2016 by Mark Laurence

This article first appeared in Pro Landscaper Gulf – a .PDF copy can be seen here on page 12.  It is based on tree consultancy work I have undertaken in Abu Dhabi in recent years.


Irrigation is taken as a necessity when landscaping in arid climates.  It is a view that I wouldn’t like to completely contradict, yet I have seen a fair bit of evidence that tells me many plantings, and trees especially, are over-watered.  Of equal importance is the fact that many of the irrigation methods are wasteful of water and sometimes damaging to the trees themselves.

 

Tree sprinkler damage

Lawn Watering with sprinklers is damaging the trunk of this Millingtonia


 

We have to discern the different needs of trees and understand that what is necessary for one species is overkill for another.  I particularly speak of natives verses exotics.  Ghaf and Sidr you will see growing wild and without irrigation but imported exotics need a regular supply.  I have seen Ghaf blown over in irrigated plantings, caused by shallow rooting from an easy water supply.

Bacterial wetrot in Delonix

Bacterial wetwood in Delonix regia caused by overwatering. It also reduces the flowering, for which these trees are famous.

How the water is put on is just as important; pop-up sprinklers in lawns can damage the trunks of trees, causing aerial rooting in species like palm or fig, discolouring bark and causing stress-induced rots to occur in others.  Exotics like the Flame tree (Delonix regia) get over-watered, causing a reduction in flowering and a susceptibility to bacterial wetwood (slime flux). Even drip irrigation is not ideal, as it applies the water at the surface and promotes shallow rooting.  Trees with shallow roots are vulnerable to drought and so dependent upon the irrigation supply – a vicious circle.

Excess surface irrigation is wasteful.

Excess surface irrigation is wasteful.

In the UK, we are used to putting in a subterranean irrigation ring around trees, which gets water to the tree roots at a deeper level.  For watering established trees, perforated tubes can be utilised, inserted vertically throughout the root zone and either manually watered, or connected to standard irrigation systems.  Supplying water at a slightly deeper level means less water used and wasted. A word of warning though – most feeding roots occur in the top 300 – 500mm of soil, so watering too deeply can also be wasteful.

Tree roots growing along the line of irrigation pipes

Tree roots growing along the line of surface irrigation pipes

In coastal cities, problems can arise from a naturally high-level, saline water table.  Halophytes (salt tolerant plants) have evolved to cope with this, but for some imported species, salinity can be a problem.  You also have to be aware of the quality of the irrigation water itself, which if drawn from the ground, may have a high saline content. Get your water supply tested if you are unsure.

 

Ultimately, I believe that planting styles and expectations of “landscape” must change.  A more natural style, with more xeriscaping and use of natives or other arid loving plants from different parts of the world (but from similar conditions), will emerge.  More important, in my view, than using strictly native species, is building plant communities that function and thrive in place without much human care or maintenance.  As climate zones shift rapidly around the world, nature cannot keep up and it will be down to us to create landscapes that sit well in their altered environments, whether native or not.  I believe we can do this with considerably less use of irrigation.  The water we do use should then be grey water (from taps and sinks), which is a much better way to conserve processed water use.

Canopy of Delonix regia

Canopy of Delonix regia

The goal has to be minimal water use, natural, ecologically benign planting and urban environments which feed our biophilic needs for connection to nature.

Zizyphus spina-christi

Zizyphus spina-christi, crown of thorns tree. A native of the UAE

Posted in Arboriculture, Dubai, UAE, Ecosystem Services, Environment, landscapes, Middle-East, Trees Tagged with: , , , , ,

regenerative tree planting methodology
December 29th, 2015 by Mark Laurence

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 regeneration

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

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

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: , , , , , , , , , , , , , , , , , ,

December 7th, 2014 by Mark Laurence

Last winter I did some interesting work in Abu Dhabi, concerning the care of trees.  I can’t name one of the projects (a royal palace), but one was Mushrif Central Park undergoing a major redevelopment (and now reopened – March 2015).  In both places I undertook a survey of 100+ broadleaf trees (as opposed to palms), assessed their condition and trained staff in basic arboricultural pruning techniques.  Such information is lacking out there as most such trees, with the exception of things like ghaf (Proposis cineraria) and acacia (A. tortilis) are imported from abroad, so knowledge of the necessary arboricultural techniques of pruning, especially of broadleaf trees, is generally absent (palms they are well used to dealing with).

 

As you can see in the pics, the trees in the park had been “salvaged”, which is perhaps not a good word. A specialist tree-lifting company from the US had been engaged to train ground staff in the techniques of boxing and lifting the trees, no easy task in a pure sand soil and 35-40degC – and that’s the winter temperatures. I then had to attend to the care and aesthetics of the tree.  My assessment was that most of the trees had been badly pruned in the past, causing poor crown developments and in some cases allowing disease to enter.

Containerised Trees in the nursery area

Not surprisingly, some of the trees suffered severe shock in being lifted, but most survived, with varying degrees of die-back and then regrowth. Much of the work was simply about deadwooding and the teaching of correct pruning cuts and methods. Access is always the main issue and there was no way to teach the guys how to climb – that is a job for a specialist training school, so we were restricted to a cherry-picker and for the most part, hand tools.

Pruning

Many trees suffer, surprisingly perhaps, from over-irrigation. This causes surface rooting which makes trees dependent upon continued irrigation, plus natives like ghaf become prone to wind-throw from lack of deep anchor roots. Exotic trees such as Delonix (below), grown for their beautiful red or yellow flowers, bloom less well when over-watered and become prone to bacterial wetwood infection.

wetwood

Places like Dubai and Abu Dhabi are developing at an astonishing speed and their landscapes are growing at a similar rate. Knowledge is the thing that lags behind, and it will take some time for this to catch up. I’m sure it will; there is something alluring about creating beautiful landscapes in a naturally hostile climate. This becomes a critical issue in the light of climate change and global urbanization, which is happening fastest in the hotter regions of the world; landscapes moderate climate and make such places livable, whilst biophilia demands that we need close contact with greenery in this urbanised world.

More needs to be done to increase the knowledge and care of trees, including species selection and nursery practice, reducing over-irrigation and teaching good pruning methods, but it can be done. I’m looking forward to the next phase.

Posted in Arboriculture, Dubai, UAE, Environment, landscapes, Middle-East, Trees Tagged with: , , , , , , , , , ,

December 19th, 2013 by Mark Laurence

I am working as a consulting arborist in the UAE for a couple of large projects.  Whilst there, I have been observing the broad state of the art and there is a long way to go in bringing across current best practice to the Middle-East, and I suspect that is so for many parts of the Middle-East and Asia.  Even in my village in Sussex, in the last month tree butchery has occurred, so the UK still doesn’t always get it right, despite a long tradition of arboriculture.

I have always worked in accordance with the advise given by Dr. Alex Shigo, of the US Forest Service.  His investigations revolutionised our understanding of the way trees react to injury, and this should inform the inquiring arborist.  Sadly not everyone inquires.

Delonix trees in a public park in Dubai - note the cracked branch over a footpath!

Delonix trees in a public park in Dubai – note the split branch over a footpath!

Back to trees in the UAE.  What I am seeing is a gradual awakening of interest in the care of trees, and the acknowledgement of the skills needed to carry out that work.  It seems that as more emphasis is put on landscape and more trees are planted, there comes a point when caring for them becomes a higher priority.  This needs to go right across the board, to include the correct pruning in the nursery, this can save many years of bad growth habit, which is not always correctable later.  Prevention is always better than cure. Perhaps the UAE, and especially Dubai, is maturing to the point of switching from development to maintenance. That’s as true for arboriculture as it is for plumbing and building maintenance.

A part of my contracted work is to train local teams in the correct methods of pruning. Basic techniques can be taught, but in the UK it takes three years to train an arborist, so we have to be realistic in what we can achieve. I think it won’t be long before I have UK based arborists over there caring for trees. With the 2020 World Expo now secured, the demand for trees can only grow, whilst in Abu Dhabi a new law requires 25% of all ground space on a development to be landscaped – the demand for beautiful trees has never been greater, nor the need of skilled care more evident.

Posted in Arboriculture, Biophilia, Dubai, UAE, Environment, landscapes, Middle-East, Trees Tagged with: , ,

November 26th, 2013 by Mark Laurence

Here are some pics from my garden; they tell of Nature’s rhythms and how they effect our lives…

Miscanthus seedheads

Miscanthus seedheads

Chestnut Logs for the Stove!

Chestnut Logs for the Stove!

Golden Leaves of Hazel

Golden Leaves of Hazel

Last of the Elder Leaves

Last of the Purple Elder Leaves

 

Posted in Arboriculture, landscapes, My Garden, Trees Tagged with: , , , , ,

July 26th, 2013 by Mark Laurence

This ASLA (American Society of Landscape Architects) animation does a great job of explaining the need for trees.  One minor criticism: the part which shows the trees’ underground root structure shows it way too small; should be at least twice the radius, if not three times.  Never mind, worth a watch:

Posted in Arboriculture, Environment, landscapes, Sustainability Tagged with: , ,

January 16th, 2013 by Mark Laurence

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: , , , , ,

November 12th, 2012 by Mark Laurence

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: , , , , , ,