Greening the City

Department: Landscape Architecture
Active Dates: 2012 – 2019

Principal Investigator: Matthew PRYOR (PI), Yuxiao CHEN (Co-I)
Funding body: HKSAR Collaborative Research Fund


From the outset, Hong Kong has had a highly compact urban form. Green spaces within the city have typically been very small and infrequent, street corridors are highly contested environments (in plan and section). Huge spatial and operational challenges have to be overcome in order to maintain any significant greenery or urban forest. This research initiative explores a broad spectrum of technical and operational issues involved in establishing and sustaining vegertation in high density cities. It includes separate studies on the production, planting, arboricultural maintenance, protection of trees and transplanting of street trees in high density urban environments, and addresses the historical perspective, the underlying arboricultural science of trees in the street and the development of best practice standards.


The study aims to develop specific practical knowledge relating to the growth of trees in high density urban environments, and how these can be modified to improve the health of our urban forests.


The study has produced a range of academic and best practice outputs covering the vegetation of slopes, street tree planting, and landfill restorations.


Academic Outputs

  • Pryor M.R., Hau C.H. and Watkins A. GEO Publication 1/2011 – Technical Guidelines on Landscape Treatment for Slopes. Geotechnical Engineering Office (GEO) of Civil Engineering and Development Department, HKSAR Government, Hong Kong, 2011, 220.
  • Pryor, M., Street Tree Planting in Hong Kong in the Early Colonial Period (1842-98). Journal of the Royal Asiatic Society Hong Kong Branch. Vol 55.
  • Pryor, M. A tree preservation ordinance for Hong Kong: An historical note. Yuan Lin 2015.
  • Pryor, M. (2012). Street Tree Planting (Ch.7) and Street Tree Establishment & Maintenance (CH.8). In Development Bureau HKSAR, Comprehensive Street Tree Management Plan for Hong Kong (confidential report).

Conference Papers, Other Outputs, Awards

  • Pryor, M. (2014) The challenge of planting trees on slopes in Hong Kong. 7th Annual International Arboriculture Summit – Hong Kong. (November 2014)
  • Pryor M. and Chen, Y.X., Landfill after use: planning for acceptance. In proceedings of 15th International Waste Management and Landfill Symposium. International Waste Working Group, S. Margherita di Pula, Sardinia. Italy. October 2015.
  • Central Reclamation Ph.III – Independent Technical Review of Koelreuteria paniculata Trees along Roads P2 and D6. HK12/02 (2013-14).
  • Kowloon Park / Haiphong Road Old & Valuable Trees
    – Technical Specialist (for LCSD) (2013-14).
  • Kennedy Town Station – Protection of stonewall trees at Forbes Street (for MTRC). (2010-2015).
  • A Comprehensive Street Tree Management Plan for Hong Kong” undertaken by Urbis Limited for Development Bureau (role, contributing author / team member)
    – Landscape Institute UK Award 2014 : Winner – Landscape Policy & Research
    – HKILA Landscape Awards 2014 : Silver Medal, Landscape Management Category

Anticipated Outputs

Pryor M., Ng, C.W.W., Chen, Y.X et al. Development of reliability-based preliminary design guidelines for live covers for man-made slopes and landfills. (est. 2016)

Anticipated Impact

The research is intended to improve the qulaity (healthy, longevity and biodiversity), type and extent of vegetation throughout the city. Although focused on Hong Kong, the outputs are directly relevant to high density cities in any tropical/sub-tropical climate.

Enlarge Photo: Greening the City 1