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Posts tagged ‘arboriculture’

Environmental change: awareness, actions, aspirations

September 1, 2015

Gabriel Hemery

Environmental change is impacting Britain’s trees and forests with increasing frequency and severity, caused by human influences and/or natural ecological processes.

Somerset owner William Theed replanted with different conifer species when Japanese larch in his woodland was the first in the UK attacked by Phytophthora ramorum. Photo Gabriel Hemery.

An important national survey about environmental change is seeking to explore awareness, actions and aspirations among all those who care for trees. It is open until 15th September and I encourage all those with a deep interest or professional connection with trees and forestry to take part.

If you can spare about 20 minutes you will be guided through a set of questions tailored to your role (namely woodland owner, professional forester or arboriculturist, tree nursery owner etc.). These cover the following broad themes:

  • What do you think about environmental change?
  • Have you been affected by environmental change?
  • What are you doing about making our trees and forests more resilient to environmental change?

Survey co-ordinators the Sylva Foundation report that over 1000 responses have been received to date (see Twitter), which is impressive, but more responses will mean more powerful science and better informed policies. This is an opportunity for many new voices to be heard on a very important subject.

Please take the survey

More about the British Woodlands Survey 2015

The national survey is aiming is to help understand progress in awareness and actions in adapting to environmental change among woodland owners and managers (including agents), tree nursery businesses, and forestry professionals.

The information gathered will be used by organisations, policy makers and researchers to help improve the resilience of the nation’s forests. The results will inform the government’s National Adaptation Programme.

The British Woodlands Survey 2015 on Resilience is supported by a very wide number of organisations, with funding provided by the Forestry Commission and the Woodland Trust. It is hosted and co-ordinated by the Sylva Foundation.

The survey is live from July 31st to September 15th 2015.

Take the survey:

Woodland biosecurity – a simple guide

November 11, 2012

Gabriel Hemery

Brushing boots to disinfect and sterilise

Biosecurity – preventing the introduction and spread of harmful organisms – is big news at long last! The arrival of Chalara fraxinea in Britain has brought this important issue to the fore. However, I found it difficult to find simple guidance on the steps we should take when visiting or working in woodlands, or with individual trees in our trees and cities. Many of the record number of readers of this blog over the last week have found it after using searches such as:

“what should I do if I find Chalara fraxinea?”
“how do I clean my boots?”

While we wait for more detailed specific advice to come from scientists and Government officials in relation to Chalara fraxinea it would be prudent to follow the protocols developed to minimise the spread of another pathogen; Phytophthora. So my first recommendation is to visit the Forestry Commission’s webpage on Biosecurity Measures, which includes the advice currently given to all Forestry Commission staff for their routine visits to woodlands in a handy pdf guide.

I have put together the following simple guide on woodland biosecurity.

Biosecurity behaviour

Brushing boots to disinfect and sterilise

Brushing boots to disinfect and sterilise

  • Clean your footwear after visiting a woodland. Wear Wellington boots, as these are easier to clean thoroughly. To do this effectively you must remove first all soil and leaf litter from your soles. You will need water and a stiff hand brush.
  • If you have been to a high risk site apply a detergent to sterilise them, although it is good practice after all visits.
  • Sterilise your tools. Be careful that the chemicals you use do not harm trees (or other wildlife). Read more about sterilising forestry and woodland tools.
  • If you drive into a woodland, even on a road, wash your tyres to remove soil and leaf litter.

Biosecurity personal kit

Spraying boots to sterilise with Propeller disinfectant

Spraying boots to sterilise with Propeller disinfectant, after they have been brushed to remove soil

The most common question I’m asked is what chemical should I use to sterilise or disinfect. The one recommended, or at least adopted, by the Forestry Commission currently is Propellar™. This is available only directly from one supplier (see below) and must be ordered wholesale in 12×1ltr containers as a minimum order. I was amazed when I searched the websites of two of the major forestry and arboricultural supply companies that neither had any disinfection chemicals listed. This is really shocking! Try it yourself. Go to and enter a search string that allows you to search within a certain website (you will need to know the url of the forestry/arb supplier): try “ disinfectant sterilise” [replace the url with the supplier’s]. I’d be happy to be proven wrong but I’ve not found one yet that came up with any goods.

  • Propellar spray to sterilise forestry equipment

    Propellar spray to sterilise forestry equipment

    Propellar™ – chemical to sterilise footwear and equipment (always read the Health & Safety label). The supplier for the disinfectant Propellar™ is:

    Evans Chemical Supplies,
    18B Barncoose Industrial Estate
    TR15 3RX.
    Tel. 01209 213643
    Email: Evans Chemicals

  • handbrush – to remove soil from boots
  • disposable gloves – protection from chemicals used
  • safety goggles – protection from chemicals used
  • water container (e.g. 5L for personal/15L for groups) – to carry water in vehicle for cleaning after visit
  • airtight storage container – to hold brush and chemicals
  • soap and towels – to wash hands
  • bags – to dispose of material
  • storage box – to hold all biosecurity items together

If you have advice born from experience or other comments then I would be pleased to hear from you. Use the Comment box then you can share your experiences with other readers.

Finally, this advice can be followed by woodland owners, arboriculturists, foresters and anyone who accesses woodland regularly. Whether it is practicable or feasible for the average member of the public to adopt these measures is doubtful. Nonetheless, we can lead by example and on high risk sites or those with special high value (e.g. ancient trees or important habitats) particularly, it may be possible to erect signage or equipment to encourage visitors to undertake simple biosecurity measures.

Gabriel Hemery

Further Information

Beech tree rent asunder

Beech tree rent asunder

On a recent trip to a woodland in southern England I came across a beech tree that had been rent asunder by winter gales. The tree had a large fork and one of its stems had broken causing the entire trunk to split open, all the way to the ground. What caught my eye from afar was the shocking vibrancy of the freshly exposed wood inside the stem. It was almost an iridescent orange and contrasted beautifully with the bright green smooth bark.

Beech tree rent asunder
Beech tree rent asunder

On closer inspection, it became clear that damage some distance further up along the limb had allowed rot to set in, causing a structural weakness in the forked stem. Unusually though, the stem had then split halfway through and its weight had then pulled the entire forked stem away from the main stem, rather than simply splitting near to the original weakness.

Beech tree rent asunder - wider view
Beech tree rent asunder – wider view

Discussing this with the woodland owner I learnt that they have no intention to manage the tree as it is not accessible by the general public and therefore of low risk. I’m not an arboriculturist but I would be interested if any readers have some experience of this type of split. I’ve no idea either how a forester/arboriculturist would go about dealing with this if it was necessary. The amount of tension present would present a tremendous (sorry couldn’t resist it) hazard, and the partially hung limb a further complication.

Gabriel Hemery

A dendro-etymological dilemma

April 23, 2011

Gabriel Hemery

I’m a forester.  That’s a simple description of my profession without much room for misunderstanding – or so you’d think.  Therein lies an etymological dilemma for me and my fellow tree professionals.

As a forester I practice forestry, which is the management of forests.  In the public mind the term ‘forester’ is often instantly related to ‘chopping down trees’, even though forestry includes the creation of forests and their ecological management and protection,  landscape design, environmental protection, wildlife management, and recreation provision for people.  In my mind forestry is the union between trees and mankind (read more) but the fact that this is often (wrongly) seen exclusively as an economic relationship, weakens its relevance to my professional work.

I also refer to myself a forest scientist as this rather aptly describes my research activities regarding their growth, ecology and management, although it’s far from perfect as I also focus on trees as well as forests.  The term forester does not normally include an element of research or study per se.

I am also a silviculturist as I practice silviculture, or the culture of forests (from the Latin silva for forests, woods and trees).  If I were to focus more on individual trees I may prefer to call myself an arboriculturist or arborist, as I would be practicing arboriculture.  So silviculturists and arboriculturists are closely related to agriculturists or horticulturists.

I also have an interest in tree biology so I could be an ecologist, or more accurately a botanist, or more precisely a dendrologist as I study trees or woody plants or practice dendrology (from the Greek dendron meaning tree).  Or would xylologist be a better title?

All this ological discussion leaves me rather unsatisfied however, as none of the above quite fit the bill for me.  My work relates to individual trees, as well as woods and forests,  and my studies extend from tree science to the forest ecosystem.  I rather like the idea of being a silvologist and of practicing silvology.

Gabriel Hemery

Ride for Research

March 23, 2011

Gabriel Hemery

I took part in the inaugural Ride for Research today; cycling 25 miles around London’s streets, visiting three schools along the way to plant trees with children and to raise money for tree research.

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We visited three London schools en route: two primary schools at Harrow and Islington, and a secondary school at Hampstead.  At each school we were welcomed by the local Mayor and enthusiastic children.  They learnt a little from us about Acute Oak Decline: the disease that we were raising money to support much needed research into (read more).  We planted two trees at each school: either bird cherry or rowan, and an oak.

This was the inaugural Ride for Research that was supported by the UK and Ireland Chapter of the International Society of Arboriculture (ISA).  The inspiration came from the ISA’s Tour des Trees in the USA, which has seen over 4 million dollars raised for tree research since it was started in 1991.

Organisers of the UK’s Ride for Research hope that the 2011 inaugural ride will be the start of an annual event in aid of tree research.  I had a great time and I am already looking forward to next year’s Ride for Research.  A huge thank you to organiser Russell Ball, all the corporate sponsors, my fellow riders, and last but not least to the dozens of people who sponsored me.

Gabriel Hemery

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