Johnson committed to plant 10,000 new trees in London earlier this year through a grants programme.
Arboricultural firm Gristwood & Toms applied on behalf of the London Borough of Ealing and has received a grant to plant an additional 202 trees in areas considered by the mayor's office to be in particular need of increased tree population.
Senior project manager Mark Lovejoy said: "Putting the application together was an involved process. We had to decide upon and recommend the most appropriate new tree locations initially, carry out underground surveys using radar scanning technology for each site, prepare detailed plans and, most importantly, we had to engage with the community to ensure that they were fully supportive of the proposals.
"The application process is quite complicated and time-consuming but ultimately it's well worthwhile. And now we understand the process, we'll be happy to assist others wishing to apply."
The mayor's Street Trees programme is an expansion of the Groundwork and Forestry Commission's London Tree and Woodland Grant Scheme and will run until 2012.
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