The LTOA’s Canopy Group was set up in 2011 to carry out surveys, and encourage boroughs to assess, tree canopy across the city by means of the i-Tree Canopy tool. This works by sampling aerial photosets and allocating ground cover or land utilisation types as determined by the surveyor. 

The Canopy Group carried out full detailed surveys for the whole city and a number of individual participating boroughs – and from this gained percentage tree cover figures and percentages of other categories of use and cover based on very high sample point numbers leading to low margins of error according to the programme providers.

However there were problems presented by the use of Bluesky aerial photosets in use with the i-Tree Canopy programme which led the LTOA to decide on the rapid creation of an alternative tool which could be used in conjunction with Councils’ in house GIS systems such as Mapinfo and Arcview. This was developed in a very short period by Jonathan Robinson of LB Hackney and enabled a number of further studies but with the resolution of the problems over Bluesky photography it has been found more appropriate to revert to i-Tree Canopy.

As a result the OSCCA tool has been withdrawn and the programme notes removed from the website and archived, though we view this as an example of the LTOA’s constant attention to the pressing needs of our members and the Green Infrastucture/Urban Forest profession in general.

Report from the GLA - Measuring Tree Canopy Cover in London An analysis using aerial imagery, September 2015

LTOA i-tree canopy study February 2012

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