The body's Arboricultural Knowledge course - launched this week - is aimed at those people "on the tools" who wish to acquire a more in-depth knowldege of issues such as tree identification, decay, fungi, and legal issues relating to trees.
The next session is due to run on 22 July in Somerset, but Arboricultural Association director Nick Eden said demand had been so high that another session will be organised before then.
"It is an attempt to help people who come into arboriculture on the tools and have competence in climbing and chainsaws but they want more of the background knowledge, but don't have time for university or college," he explained.
The one-day "signposting" course aims to alert arborists to wider issues around tree work, and will provide a comprehensive set of references for delegates to follow up on information.
The AA's technical officer Simon Richmond has been organising the courses and told HW there were a "huge number of people" in the situation where they have been working as an arborist for five or 10 years and realise they don't have the academic knowledge to take on a supervisory role.
Another course is also planned for 9 November, at Stoneleigh Park in Warwickshire.
For more information visit www.trees.org.uk