Tree Safety in Our School’s
TREE INSPECTIONS FOR SCHOOL’S AND PUBLIC HIGHWAYS
Trees should be inspected on a regular basis, from the point of view of both the health of the tree itself and the safety of persons in the vicinity. The reasons for this include routine management, provision of evidence for legal cases, and the preparation of Tree Preservation Orders.
In a severe storm in 1999, a fifteen-tonne ash tree fell across both carriageways of a road and onto three cars and a bus shelter in Birmingham. Three people were killed and another seriously injured. A trained arboriculturalist, it was argued by the prosecution, would have known the tree was dangerous by the fungus growing on it. The judge held that the poor condition of the tree would have been obvious to anyone making a close inspection. However, the council had no system for identifying unsafe trees along the highway. Afterwards, tests on the fallen tree found that ninety-percent of the roots had rotted away. Birmingham City Council was fined £150,000 with £56,000 costs and subsequently arranged an assessment of the condition of all highway trees.
A tree inspection may take a few seconds for a young tree, while a thorough inspection of a mature tree in an important location may take an hour or more. In some cases it may be necessary to plot the exact location of each tree on a plan, with detailed notes made regarding the condition of each tree. In these situations, a suitable computerised system is a useful aid.
The trees should be clearly identified on the plan or through the use of metal tags or similar method of marking. Unfortunately, such tags may fall off or be removed by children, or may become ingrown in the bark. However, they may not be necessary if the plan allows easy identification. Trees are of course felled or die over time, so it may be preferable to re-number all the trees in an area at each inspection.
The record made of the inspection for each tree should include at least the following information unless not relevant for some reason:-
(a) Tree number and species (both scientific and common name)
(b) Age. This is often not known, so a classification is often used such as newly planted, young, early maturity, mature, late maturity, or senile.
(c) Crown. An estimate of the height of the tree; extent of branching and foliage; description of crown width and shape, size and pattern of branches; and estimated increase in spread of the crown over the subsequent ten or twenty years.
(d) Trunk. Diameter at chest height; height of lowest branch; taper; lean; straightness.
(e) Roots. The area of ground likely to contain 90% of the root system. Distribution and pattern of root system.
(f) Condition. Categorise the overall condition of the crown; assess the condition of the trunk and branches, noting such features as broken branches, wounded or dead bark, nails, etc. The condition of the crown will allow an assessment of the condition of the roots, as will inspection of the surrounding ground (the root plate area).
(g) Evidence of past management. Check bracing, storm damage, broken branches, previously cut points, etc.
(h) The form of the tree. Record any abnormal features, such as previous pollarding, unusually light branching, etc.
(i) General notes on soil type, drains, overhead wires, nearby walls and footpaths, etc.
The inspection report should be detailed enough to form the basis for a specification for any work that needs to be carried out on the tree. The report should state whether defects in the crown have been inspected by climbing the tree, and whether further detailed examination is required.
Regarding inspection frequencies, these should be determined with regard to risk factors such as tree species, size, location, and previous problems. An arboricultural inspection is said to remain valid for three to four years. For highway trees, an annual inspection is recommended by “Delivering Best Value in Highway Maintenance”, the current “Code of Practice for Maintenance Management”. Often a visual inspection for storm damage etc. will be done by Highways Inspectors as part of their normal inspection function but they cannot of course be expected to be arboricultural experts.
At one council where the tree management arrangements were reviewed recently, a four-year cycle of inspection has been introduced. However, it was felt that the inspection frequency needed to be varied dependent on factors such as species and proximity to buildings, with some trees needing more frequent checks (as is already the case in one area) and others less frequent. At another authority, there is a three-year cycle of inspection and maintenance for all departments (with a two-year cycle for certain tree species). Clearly the expertise of arboricultural staff is crucial in determining a council’s requirements.
I would like to bring to your notice, our free Tree Hazard evaluation and inspections offer. This could cover all trees on your property and would be for the purpose of the tree’s conservation and would meet all health and safety requirements.
On completion of the inspection of each tree, we will advise you of any adversities or hazards within the trees inspected. If you require, we can supply a quotation for the remedial works, with no obligation.
A tree inspection and any required work would cover your legal liabilities (to the extent to what is considered reasonable) for tree maintenance, until a further inspection is required. (Between 1&5 years, depending on various factors).
Tree surveys can be expensive. If you are happy for Trees 1st to carry out any quoted remedial works we would be happy to waive initial inspection costs.
You are also helping to conserve the amenity of the trees in the area in which you live or work.
