Gist of the Fifth Meeting held on 3 August 2012
- TMO Inspection Report on Old and Valuable Tree LCSD YTM/11
- Members were presented with the TMO Inspection Report on Old and Valuable Tree LCSD YTM/11. Based on the recommendations in the Expert Panel on Tree Management meeting and site inspection to the subject tree on 26 July 2012, detailed investigation by removal of the surface topsoil around the subject tree with air-spade was undertaken on 31 July 2012 to further evaluate its root condition, root anchorage and the extent of brown root rot (BRR) infection.
- From the result of resistography, the average thickness of sound wood at 0.3m (above planter surface level) of the trunk was at critical risk level. In addition, there was also a large cavity.
- From the examination of trunk base and root area of the subject tree exposed by air-spade (i.e. jets of high pressure air stream) excavation, boulders were found piled tightly around the trunk base. No lignified aerial root with diameter above 10 cm was found with the boulders. The root growth was also restricted in the planter and only small diameter roots were found on top of the boulders. There was sign of BRR infection on dead root, but not on any of the roots exposed by excavation.
- Some wounds and cavities were observed on upper trunk and scaffold branches.
- While there was no imminent danger with YTM/11 as the time of inspection, the TMO recommended that the subject tree should be felled for the protection of public safety in view of its poor condition and lack of appropriate long term solution. This would allow a more comprehensive treatment to the contaminated soil in the planter and thus better protection of the remaining YTM/12 in the same planter against the disease. Alternatively, preservation of the subject tree on site might also be possible, but a tree supporting system should be installed very quickly. However, the technical feasibility of erecting a support system had yet to be studied.
- Members discussed and agreed the removal proposal.
Gist of the Fifth Meeting held on 3 August 2012