Due to recent legal advice, HCC Forestry officers have had to consider how alleged tree related subsidence claims are handled. What this has meant is that where a case is brought against us, to avoid undesirable levels of legal proceeding we have to respond in accordance with Structural Engineers’ finding. In most cases we are advised to remove the whole tree or trees depending on the claim, but what we have decided to undertake is a partial removal.
This is in the form of pollarding which is an accepted industry practice. In removing the canopy we retain the tree for as long as possible: most of the trees are well established mature specimens which offer high amenity value as well as environmental benefits. By reducing the canopy in this way we can uphold our obligations and achieve an agreed retention and future management of the specific tree.
Obviously this looks drastic to the onlooker but in most cases the highways trees are able to adapt and continue to flourish. These canopies will be placed on a cyclical management process and be re-pollarded every three years. This approach has been accepted by our legal and insurance teams who govern our actions in these circumstances.
With regards to the historical management of trees in The Avenues, I believe there is some confusion as to how this was undertaken. Visual observations clearly show that the old forest specimens were indeed pollarded (many years ago). It is clear that lapsed-pollards exist throughout the Avenues and can be readily observed. Lapsed-pollard is where the canopy has been removed in conventional pollard techniques, but then allowed to reform the canopy with few or no further reductions. This process causes the tree to become top heavy with multiple co-dominant stem growths. In most cases this produces more than average leaf density and a higher crown, as seen throughout The Avenues and across many roads in Hull.
Due to the continual financial pressures local government is facing, our department has to look at the most cost effective way of managing its Highways stock. Having mature tree specimens growing in close proximity to Victorian/Edwardian residential properties causes particular issues less notable in other areas. To manage these large canopies is not without cost and as the trees become fully mature they can create undesirable costly consequences: root invasion, subsidence, leaf fall, blocked drainage, excessive shading, falling deadwood, broken pavements etc. Many of these specimens would benefit from pollarding which would address most of these issues which Avenues residents raise on a regular basis.
In recent times the canopy management was limited to crown lifting and minimal lateral reductions. However, this approach has little to no effect on the aforementioned issues. It is at this juncture that consideration for pollarding is a more viable solution.
I think it would be prudent for all concerned to discuss this approach and develop a more flexible mind-set to canopy management. Removal of large mature specimens is undesirable and in all efforts we strive to retain these where possible.
I hope the above information clearly explains our standpoint and reasoning. I understand that this may come across as a difficult pill to swallow for some but we have to manage our stock appropriately. I would be happy to discuss this further and please return comment at your convenience.
Adam Sivell-Thompson
Urban Forestry Officer
Grounds and Open Spaces
Hull City Council
B-Line
460 Beverley Rd
Hull
HU51NE
Tel: 01482613571
Mobex: 738390
