Hazard assessment

Our hazard assessment service examines the condition of the tree and its potential to fail. We also look for any possible hazards which could affect the climber or arborist.

Any potential danger to the climber or arborist will be assessed on site prior to work being carried out.

Types of hazard which may indicate the possibility of the tree failing

A crack is a deep split through the bark, extending into the wood of the tree. Cracks are extremely hazardous because they indicate that the tree is failing.

Weak Branch Unions
Weak branch unions can occur where branches are not strongly attached to the tree. They form when two or more similar-sized upright branches grow so closely together that bark grows between the branches, inside the union. This ingrown bark does not have the structural strength of wood, which results in a much weaker union.

Decaying trees can be prone to failure, but the presence of decay by itself does not indicate that the tree is hazardous. Advanced decay (wood that is soft, punky or crumbly; or a cavity where the wood is missing) can create a serious hazard. Evidence of fungal activity, including mushrooms, conks and brackets growing on root flares, stems or branches are indicators of advanced decay.

A canker is a localized area on the stem or branch of a tree where the bark is sunken or missing. Cankers are caused by wounding or disease. The presence of a canker increases the chance of the stem breaking near the canker. A tree with a canker that encompasses more than half of the tree’s circumference may be hazardous even if the exposed wood appears sound.

Root Problems
Trees with root problems may fall without warning. Soil mounding, twig dieback, dead wood in the crown, and leaves that are off-color or smaller than normal are symptoms often associated with root problems.

Poor Tree Architecture
Poor architecture is a growth pattern that indicates weakness or structural imbalance. Trees with strange shapes are interesting to look at, but may be structurally defective. Poor architecture often arises after many years of damage from storms, unusual growing conditions, improper pruning or topping, or other damage. Any abnormalities should be examined by an arborist knowledgeable with that species of tree.

Uneven Crown Growth
Uneven crown growth can come as a result of a badly pruned a tree, or as a result of storm damage. A tree with uneven crown growth can become unstable and prone to fail.

If you are worrid about a particular tree or suitation, please do not hesitate to call us for advice.