frequently asked questions

We need a site location plan that identifies the boundaries. Google Maps® or Bing Maps® is good for this. We need to understand how the site is used, in broad terms initially, and what your objectives are for the management of your trees. Simply knowing whether you love or hate the tree, or that you are indifferent about it will help us when we are providing options for its management.

The Quantified Tree Risk Assessment (QTRA) method, developed by Mike Ellison at Cheshire Woodlands, applies established and accepted risk management principles to tree safety management. The method moves the management of tree safety away from labelling trees as either ‘safe’ or ‘unsafe’ and in most situations away from requiring definitive judgements from either tree assessors or tree managers. Instead, QTRA quantifies the risk from tree failure in a way that enables tree managers to balance safety with tree value.
By quantifying the risk from tree failure, QTRA enables a tree owner or manager to manage the risk in accordance with widely applied and internationally recognised levels of risk tolerance. QTRA also provides a decision-making framework which allows decision-makers to consider the balance between the benefits provided by trees, levels of risk they pose, and costs of risk management.

That depends on the characteristics of your trees and their location. If you follow the National Tree Safety Group guidance for domestic tree owners, and you have a population of healthy trees, it might be sufficient that you keep an eye on your trees, check them after storms for obvious defects such as splits, partial uprooting and broken branches, and then engage an arboriculturist when you identify something of concern that you’re not sure about.

How long is a piece of string? For the average person in the UK, the annual risk of dying as a result of being struck by a tree is around 1 in 10 million. To put that into some sort of perspective, the risk of death on our roads is almost 600 times greater at around 1 in 17,000 per annum. Of course, in that huge mix there is a wide range of risk and some trees do present very high risks, particularly when they are large and unstable, and adjacent to busy areas. But, importantly, most trees present very low risks.

It depends on the level of detail that you are looking for and the characteristics of your tree population and location. Big old trees adjacent to busy areas require more detailed assessment than younger trees in a low use location. Sometimes we will carry out a detailed inspection of each tree, but more commonly we carry out a Walkover Assessment, taking a general view of your trees at an appropriate level of detail, we then record individually only those trees that present significantly elevated risks, or where there is some other reason to.

Property owners and managers have a duty (under English law) to ensure, insofar as is reasonably practicable, that people and property are not exposed to unreasonable levels of risk from the mechanical failure of their trees. In 2007, The National Tree Safety Group was formed, and in 2011 it published a suite of guidance on taking a reasonable and proportionate approach to tree safety, which has been endorsed by the UK Health & Safety Executive. Take a look ( https://ntsgroup.org.uk/guidance-publications/), there’s simple, clear guidance for the domestic tree owner, and more extensive guidance for large landowners, councils, and tree professionals.

We need to know the site boundaries and the general nature of the planning proposal. If you have a detailed design, we can advise you on the likely constraints imposed by trees. Previous planning history is also helpful.
Tree Inspections and Risk Assessment

This depends on the extent of the size of the trees and whether their roots are likely to be significantly impacted by the proposal. We consider the Root Protection Area (RPA) of the tree, which is the area of ground around the tree that needs to remain undisturbed during construction operations. The RPA is initially represented by a circle that is centred on the tree stem and has a radius equal to 12 times the stem diameter measured at a height of 1.5m.

The importance of trees within the planning system has increased significantly in recent years, and the effects of development upon trees is a ‘material consideration’ in the planning process. This means that local planning authorities must consider the impacts on trees when determining planning applications.
In practical terms, this means detailed arboricultural information must be submitted where trees are present on or adjacent to a site beginning with a tree survey to the standards set out in BS5837:2012 Trees in relation to design, demolition and construction – Recommendations as a pre-requisite for the registration of planning applications.

Provide us with a short description of the tree and the signs of damage or ill health along with some photographs. We will then usually ask a few questions before providing some initial suggestions. If we can’t provide an answer, we can arrange a site visit.

It might not be necessary to intervene. It could be a short-term problem, or perhaps no problem at all. Often it is sufficient to understand what you are observing, but you can be confident that if there is a problem to be diagnosed, we are the people to diagnose it.

Maintaining age and species diversity is important in reducing your exposure to specific diseases. Be sure that any planting material that you introduce has an EU Plant Passport. Regularly check the Forestry Commission website for information of plant health threats. But most of all, recognise that people are the biggest threat to trees. Each year we meet many clients who have inadvertently killed or damaged their trees by excavation and resurfacing, building, altering soil hydrology, lighting fires, tipping garden waste, inappropriate pruning, and so on.

The larger pests are horses, cattle and sheep trampling the ground in which trees are rooted, and often browsing on the bark of trees, which can lead to their rapid decline. Deer might de-bark trees whilst rubbing their antlers to remove felt. Next are grey squirrels, which browse on the shoots and bark of trees, followed by birds including pigeons and parakeets browsing on buds and young shoots. There are many insects, fungi, viruses and bacteria, most of which play beneficial roles in ecosystems, but when they are introduced from abroad and find new hosts, some of these caon have devastating consequences. Some of the most recently introduced are Asian Longhorn beetle (Anoplophora glabripennis) and Ash dieback disease (Hymenoscyphus fraxineus)

We will:

1. Carry out a preliminary assessment of tree condition, mechanical integrity and general suitability for retention, subject to suitable access being available
2. Assess the potential influence of trees upon load bearing soils beneath the subject property based upon our observations on site, up to three soil core samples extracted by hand auger, and data from the British Geological Survey when available
3. Assess the potential for trees to displace structures (buildings, garden structures, hard surfacing etc.) via direct contact
4. Assess the potential for ingress of tree roots into drains
5. Carry out a preliminary assessment of neighbouring trees (as viewed from the subject property) where considered appropriate by our surveyor
6. Supply a report detailing the species, approximate dimensions, observations and locations of trees, and providing guidance on the future management of trees on the subject property.

Our consultants hold a range of qualifications from certificates to professional diplomas and degrees. Mike Ellison and Glyn Thomas are experienced in providing a wide range of expert evidence in relation to neighbour disputes, subsidence damage, trees and the planning system, work related accidents, and tree safety management.