They have criticised CABE for a lack of representatives with tree expertise in its design review panels and as space enablers.
In a statement issued to the press last week, International Society of Arboriculture president-elect Colin Bashford said he was "amazed" that CABE considered landscape architects to have the knowledge to advise on tree issues.
"Such action is clearly unacceptable and without merit because, with the best will in the world, landscape architects - and I work with and admire so many - can never be correctly described as specialists in trees," he explained.
Bashford's comments follow a call made by Trees in Towns II author Mark Johnston at the Treework Environmental Practice seminar on 19 November. Johnston told HW that the emphasis on green infrastructure should have highlighted the role of arboriculturists.
"Trees are the single most important element of green infrastructure, but if you look at CABE's list of space enablers, there isn't a single arboriculturist on it. I think that's really remiss," said Johnston.
CABE argued that the extensive representation of landscape architects in design reviews and as space enablers brings in expertise and said it works closely with experts in the arb sector as well as being an active member of the Trees & Design Action Group.
But tree consultant Jeremy Barrell blasted the organisation for its lack of arboricultural recognition. "It very much concerns me that there is a perception within CABE that landscape architects are able to advise as specialists on trees," he said. "Our experience is that landscape architects do not generally have the expertise to be able to comment on any specialist tree aspect beyond the superficial visual characteristics."
CABE head of research and futures Edward Hobson responded: "CABE does not rely solely on landscape architects for arboricultural advice. We draw on specialist expertise from our broader enabling panel. We fully appreciate and value the critical importance of trees within the built environment."
A representative added that two free places to CABE Space's leaders programme were awarded to arboriculturists this year.