Farrell said: "The many challenges that we now face to make our cities, where the majority of the population live, safe and healthy places mean that we will have to re-think the future of urban design to include more vegetation.
"The concept of ‘landscape urbanism’ is gaining professional and political traction on mainland Europe, with an approach based on organising cities through the design of the city landscape rather than by the design of its buildings. Combined with the current trend to move away from prioritising cars for urban mobility, this has already started to make a strong impact on the design of streets and the wider urban public realm."
Farrell said that urban trees play an essential role in shaping local landscapes and providing life-critical services but a strategic approach was required to ensure that role was maintained and enhanced.
He said that addressing tree diseases was crucial and added that the London National Park concept, currently being considered by the Mayor’s team, would be "hugely influential in better planning green infrastructure" in the capital.
TDAG was formed early in 2007 following a round table discussion convened by Martin Kelly, then director at Lovejoy London and now land planning director at Capita Property and Infrastructure and became a charitable trust in 2013. The group early on set out a 10 Point Action Plan1 and this continues to guide its work. Over the past eight years TDAG has grown in membership and influence.
Two group has produced publications Trees in the Townscape: A Guide for Decision Makers2 (2012) and the companion document Trees in Hard Landscapes: A Guide for Delivery3 (2014)