Category: Arboriculture

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: , , , , ,

hazel pruning methods
January 9th, 2016 by Mark Laurence

In my previous post I talked about a regenerative planting methodology for urban landscapes, in which I suggested you would manage, rather than maintain your planting areas. So how exactly do you you do this? Both involve work and the difference is a subtle but important one, in both attitude and application. Think urban forester rather than garden pruner. The picture above illustrates this perfectly, so let me explain.

It shows two hazels in my garden, both planted as young bare-root trees in the winter of 07/08. The one on the left was coppiced down to the ground in the winter of 12/13, the other has been pruned to keep a structure of older wood, with all suckering growth removed annually. What is the difference? The coppiced hazel has been less work overall and has not been touched since it was coppiced, the pruned tree has been pruned annually, which was not great amount of work but this is just one tree. If there were a hundred, it would be a different matter. The main difference is that the pruned tree has catkins, the coppiced tree does not, but I think this is a difference of genetics, rather than pruning technique, as they have always been like that. The shape of the pruned tree is also wider in its spread and will become gnarled as it gets older.

So in terms of management, if you go the coppice route you do nothing much to the trees except coppice them every 4-5 years. I would suggest that 50% of the trees are coppiced so that not all structure is removed at once. Notice that the growth of the coppiced hazel is straighter, making for a productive yield of canes and poles that can be used in the local community. Other trees that can be coppiced include sweet chestnut, lime, alder, ash, willow and hornbeam. Birch and oak will coppice, but from young trees only. Willows and dogwoods grown as bushes for their winter colour can be coppiced or “copparded” (inbetween coppice and pollard) to around 300-600mm every two years to keep the winter stem colours strong.

Salix elaeagnos

Salix elaeagnos (foreground)

By adopting such techniques in our larger masses of urban street planting and parks, we would deliver a more biodiverse, beautiful and biophilic interaction for all concerned. It would also cost less both to establish and possibly to maintain, than traditional planting. The above willow is beautiful and graceful, yet I have seen it all too often used in municipal car-parks and reduced to a-n-other shrub that is caressed all to frequently with the indifference of a hedgetrimmer.

Time to re-wild our inner selves, and our urban landscapes. We can do so much better than the average landscape we see in our towns and cities.

Posted in Arboriculture, Design, Ecosystem Services, Environment, landscapes, My Garden, Regenerative Planting, 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.


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.


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: , , , , ,

September 20th, 2013 by Mark Laurence

I launched my newsletter this week on vertical greening, sending it out to clients and those who’d signed up here or on the website.  From the number of views and feedback, (considerably higher than industry standards) I’d say it was a success!  The aim is to inform interested parties of news and developments in the field of vertical greening.

Don’t miss the next issue – sign up using the form on the right!


Posted in Arboriculture, Biophilia, Design, Dubai, UAE, Environment, Indoor Plants, living walls, Retail, Sustainability, Vertical Greening 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: , ,