Tree Surgery to a Mature Tree in Abu Dhabi

I recently supervised a major crown reduction on an over-mature Eucalyptus on an historic site in Abu Dhabi. 

I had surveyed the tree last year and made a recommendation to carry out a substantial crown reduction, due to the declining vigour of the tree and the close proximity to people and buildings.

We used a MEWP (mobile elevating work platform) to access the tree and do works to the lower areas of the crown.  The top branches were removed by use of the site crane, which could lift substantial sections of the tree and bring them safely to the ground.  I have some great video’s which I may post at a later time.

Tree Surgery to an old eucalyptus, Abu Dhabi
Tree Surgery to an old eucalyptus, Abu Dhabi

Needless to say, this type of work needs a skilled arborist and crew to carry out, which we used.  If you have complicated tree works that need carrying out, do get in touch…

Lighting Fixtures in Trees

On my last few trips to Dubai, I have been noticing a lot of trees with lighting installed in them.  Whilst these can create stunning effects at night, the correct methods of installation and maintenance are essential for the long-term well-being of the tree.  We have to put the needs of the tree first – if the light effects are more important, then just don’t use a tree!  Much of what I have seen – and this applies world-wide, not just in the UAE (I have seen equally bad wiring in the UK, Chicago, etc.) – is messy and very likely to cause long-term damage to the tree, if it doesn’t kill it entirely.

Incorrect attachment of electric cables to a tree
Incorrect attachment of electric cables to a tree. Cable or zip trees around the circumference may kill the tree, or will become overgrown by new cambial growth.  Excess cable coiled at the bottom is not needed – a light fixed at 10m high stays at that height.

We have to reconcile the fact that trees expand in girth year on year (including palms, though in a different way) through what is termed secondary growth. All this growth happens in the region just under the bark in the cambial layers and produces new meristematic tissue. Damage or restrict this layer and it effects the whole health of the tree.  Cable ties are like a choke collar to a tree; as it grows it gets choked.  Many trees will solve this by growing over such a restriction but this can leave the wood vulnerable to infection and mechanical stress.  Likewise, light mounting brackets screwed directly onto a tree become overgrown and are again a source of potential infection.

messy cabling in trees
This is a mess; transformers should be left on the ground and cabling should be neat and minimal, again, without girdling ties

If the aim of lighting is to create an aesthetic effect, it should not be at the expense of the trees aesthetic, nor of it’s health.  I can’t imagine that the lights above look very good at night, although i wasn’t there to see them on.

There is a correct way to do all this and keep the tree in good health (as far as any interference can be healthy).  If you have such a project, either existing or potential, please contact me to discuss assistance in achieving best practice.

Pruning of Broadleaf Trees in the UAE

Split branch in mature ghaf, fallen int its neighbour

I have said elsewhere that the landscapes of Dubai and Abu Dhabi are growing (no pun intended) at an extraordinary rate and that the knowledge and skills needed to care for the landscapes as they mature are not keeping pace.  This is especially true when it comes to trees.

Palm trees are familiar to the region as a crop tree; they are tough, easy to move without too much worry and of simple form which does not necessitate any complex pruning.  Broadleaf trees however, demand more than the crude lopping they are so often subject to, especially in urban spaces where there are issues of health and safety.  Bad pruning, but also lack of pruning can lead to dangerous conditions.

The following two pictures show dangers from no pruning care taken:

Delonix split branch
Lack of awareness – split Delonix branch over public path. Here, lack of any pruning leads to a potential danger to the public.
Years of neglect for these trees
A fallen Albizia tangled into a Ficus – caused by years of neglect

Often a tree’s lifespan and health are determined even before they are planted on a site. Many problems come from lack of formative pruning right at the nursery stage and roots may be damaged during lifting or potting on.

Poor care at the nursery stage has caused significant damage
Poor care at the nursery stage has caused significant damage. The tree may never regain its health or vigour.
Lack of care and attention in the nursery has damaged these trees for life
Lack of care and attention in the nursery has damaged these trees; pruning to correct poor shape is easy if done when very young, difficult to correct in trees like these (removing one of the co-dominant stems in the left picture will unbalance the tree, leaving it will ensure future failure). Such faults left in the tree, however,  may be impossible to alter as it matures.  It doesn’t need training to know that you remove tree-ties before they get trapped.

So many trees are off to a poor start before they are even planted but once they are, environmental factors will kick in.  How well they are planted and irrigated will effect their health.  Assuming they survive and grow (and the average life-span of a UK planted urban tree is less than 10 years) then they have to cope with the occasional pruning that they are given and the damage that this may cause.

We have to understand that trees never heal.  They survive damage by a process of isolation, or compartmentalisation, whereby cells surrounding damage isolate this area from the remaining areas of the tree.  Unfortunately, bad pruning tends to rip right through these natural defenses, opening up the tree to infection and decay.  Key to this is understanding the correct and   way to place cuts.  Here’s how you DON’T do it:

Stubs with tears on a Delonix caused by incorrect pruning methods
Stubs with tears on a Delonix caused by incorrect pruning methods. Tears have ripped through the collar.
Incorrect pruning has torn through the collar and the natural defense mechanism of this ghaf
Incorrect pruning has torn through the collar and the natural defense mechanism of this ghaf
These may "only" be damas trees (and best not planted) but this is still a terrible abuse
These may “only” be damas trees (and best not planted) but this is still a terrible abuse. Excuse the poor photo, snapped in Abu Dhabi.

All these abuses and bad practices can be seen anywhere in the world, even in the UK which has a thriving profession of arboriculture.  Trees in hot climates are critical, however, to the health of people and the city overall.  As the landscapes of our modern cities and mega-cities continue to grow, and the effects of climate change become more severe, we need to look after our trees – everywhere – to a much higher standard than our current levels.

Trees deserve our respect – and our thoughtful care.  More, they deserve active and knowledgeable management and the correct level of arboricultural skill and care to ensure they thrive and serve us, and our built environments, as best they can.  The more we give, the more we get back.

Baobabs, Tree Surveying and a Walk in the Park

On my latest visit to the UAE I had a number of tree-related experiences.

In Dubai, I met with James Palmer from WT Burden, to view the Baobab trees they import from Australia. These trees are succulents, so don’t possess the usual vascular system. As such, they are huge water storage tanks and can live uprooted for two years (I believe the biggest weighed 11 tonnes)! The trees in the picture were planted in January and are just now coming into leaf, as the season warms up. I will follow these closely as I’m intrigued about how well they will re-form a good crown shape.

Baobab trees, Dubai

I also got to have a fabulous green tea in the Four Season’s hotel, which was nearby.  The landscaping there is sublime, with beautifully terraced stone walls and planters to the roadside boundary and a form of living wall with horizontal planters built into a curved wall.

In Abu Dhabi, I was commissioned to carry out a survey on a large tree, which is located on a site I cannot name.  The tree itself is large and in gradual decline, so needs some help.  Following a thorough inspection from the ground and also using a MEWP, I will return in the Autumn/Winter to oversee a crown reduction.  It’s great to see such care and concern being placed on trees, they are the stuff of life!

I also got a chance to visit Umm Al Emarat Park (formerly Mushrif Central Park), to see it finished and to look for the trees I surveyed and made pruning recommendations on, back in 20 14.  It is obviously now completely different, the trees I worked with had all been lifted and containerised for re-use in many different areas of the park. Saw some I could recognise though, like seeing old friends!

This shows a few of the trees in 2014 which had been lifted from the old park and saved for re-use. I surveyed each tree and made recommendations for pruning works, then trained the landscape crew in the correct pruning methods to carry out the works.

One of those trees (Ficus nitida) in its new home and looking happy.

I would like to have had more time there, and will visit again.  I note an on-going need for aboricultural advice there to maintain the trees in the best of conditions…