LCQ12: Government's tree care work

Following is a question by the Hon Lee Wing-tat and a written reply by the Secretary for Development, Mrs Carrie Lam, in the Legislative Council today (October 22):


Recently, there were a number of incidents of large trees collapsing, which have aroused public concern about the Government's tree care work.  In this connection, will the Government inform this Council:

(a)  of the names of the government departments currently responsible for tree care, the number of staff concerned in each of these departments and their areas of responsibilities;

(b)  of the details of the procedure adopted by the Government for routine inspection of trees, including the average number of health assessments conducted for every tree in each of the past three years, the tree health and safety rating system currently adopted and the methods of tree care;

(c)  of the government departments which have out-sourced their tree trimming work and the locations of the trees concerned; the government departments which perform the tree trimming work themselves or entrust the work with other departments; and the relevant professional qualifications possessed by the staff in the departments who perform such work; and

(d)  whether the Government had reviewed in the past three years the existing methods for trimming trees on government land; if it had, of the dates and details of such reviews; if not, whether it will conduct a review in the near future so as to avoid endangering the health of trees by using improper tree trimming methods?



(a)  The government departments responsible for tree maintenance, the number of their staff involved and their scope of responsibilities are as per Annex.

(b)  Inspection of trees

Concerned departments formulate frequencies and methods of inspection for trees under their purview having regard to practical considerations such as planting environment, species and maturity of trees.  For instance, HyD conducts regular inspection of the trees under their purview at least twice a year.  LCSD also arranges regular inspection at least once each year for normal trees and at least two detailed inspections for trees in the Register of Old and Valuable Trees.

Maintenance of trees

Concerned departments have all prepared guidelines on inspection, examination and pruning of trees under their purview and may also employ approved contractors with horticultural qualifications and appropriate experience to carry out tree inspection, assessment as well as maintenance work (such as watering, fertilising, disinfesting, pruning withered branches or those which likely affect traffic, trimming overgrown trees and removing withered ones).

Classification of trees according to their conditions

 HyD has adopted the following classification for the health conditions of trees–

* any withered branches;
* any pests and diseases;
* any danger of collapse; or
* already withered (dead).

LCSD assesses the health conditions of trees on the basis of size of leaves, colour, tree form, any abnormal defoliation, trunk holes, decayed branches and roots, as well as any attack by diseases and pests.  Other departments will also take appropriate measures in the light of the health and other conditions of trees.  If trees are found to be affected by diseases and pests, departments concerned and their contractors will apply appropriate treatment to make them recover. Removal of trees will only be considered if there is no feasible method to prolong their lives and the trees are posing potential danger to the public.

(c)  All government departments mentioned in Item (a) have outsourced the pruning of trees under their purview.  Locations of outsourced work include public housing estates, slopes, retaining walls and highways.  The staff of departments concerned will monitor and ensure the quality of the contractors' work.

Apart from outsourcing the pruning work of trees under their purview, AFCD and LCSD also execute some of the work themselves.  The pruning work undertaken in-house by AFCD is supervised by Forestry Officers belonging to the professional grade and Field Officers with relevant experience.  The in-house pruning work of LCSD is carried out mainly by its tree teams.  Tree team staff have received proper training, including horticulture maintenance and arboriculture training programmes organised by LCSD's training section.  The supervisory staff of the tree teams have received more specialized training such as British National Certificate Course in Horticulture (Arboriculture).  Some of them also possess the qualification of Certified Arborist of the International Society of Arboriculture.

(d)  In February 2007, the then Environment, Transport and Works Bureau reviewed and compiled the General Guidelines on Tree Pruning.  The guidelines describe the types of pruning, safety measures, pruning techniques and points to note in such operations.  Departments concerned have also formulated their own guidelines in line with their specific needs.  In formulating the guidelines, we have made reference to international standards on arboriculture and taken into account the practical conditions in Hong Kong.  In March 2008, LCSD reviewed their guidelines on tree pruning and enhanced the rules of safety at work to avoid causing danger to the public and staff.  ArchSD and HyD also conducted reviews in May 2007 and July 2008 respectively and introduced the latest international standards on tree maintenance and pruning.  We will make appropriate improvements to the pruning guidelines when necessary.

Ends/Wednesday, October 22, 2008
Issued at HKT 15:15