A key objective of the LTOA is to 'Improve the health, increase the extent and guarantee the resilience of London’s tree canopy'

Despite the many positive changes, and increases in awareness, understanding and practice in recent years in relation to our natural heritage and care for our environment, we are beset everyday by greater threats to the ecosystem we inhabit.

The LTOA is responsible for much of London’s tree population, a fundamental part of the environment, and the keystone species that support humans and wildlife and interconnect the entire city’s natural and physical processes, its water, soil and the very air we breathe.

We are increasingly informed about the importance of our tree canopy for air conditioning, and managing water, soil and drainage systems, the effectiveness of which is essential to the quality of urban living. The increasing risks of new pests and diseases to London’s trees, if unchecked, threaten the canopy and skyline as we know it today.

The prospect of such declines and losses places a clear responsibility on government, municipal managers, LTOA members and the public to invest in protecting our trees if we are to secure and enhance their contribution and continuity for the benefit of city life.

This position statement reflects current concern about a number of significant pest and diseases threatening the health of London’s trees, including:

  • Acute Oak decline (AOC)
  • Canker Stain of Plane (CSP) Ceratocystis platani
  • Chalara Ash Dieback (CAD) Hymenoscyphus fraxineus
  • Horse Chestnut Leaf Miner (HCLM) Cameraria ohridella
  • Massaria Disease of Plane (MDP) Splanchnonema platani
  • Oak Processionary Moth (OPM) Thaumetopoea processionea

To read the full report 2nd Edition January 2017, click here to download it as an Adobe Acrobat document (PDF)

Pests and Pathogens of London's Trees

The LTOA biosecurity working party has drawn up a matrix showing the pest and pathogens of London's trees. Listing pests / pathogens and species affected, diagnosis, prognosis, management and information links. Click on this link for the matrix.

The LTOA website is sponsored by:

How to Become a Member

Members can attend, for free, the LTOA meetings which are held four times a year and cover a wide range of tree related matters.

Click here to find out how to become an associate member