"I fear for arboriculture full stop," said Tree Life Arboricultural Consultancy founder David Dowson. "The decisions (on which courses colleges run) are made by finance managers.
"Arb courses are expensive to run. The staff-student ratio is about one-to-four for chainsaw courses - far more than for, say, small animal care. Colleges chase funding so they pop in and out of subjects. You don't know what will be run in future."
The industry is not as aware of the problem as it ought to be, he added. "It is hoping that everything will be okay and it is reluctant to engage with educators. But unless the industry gets involved more in education issues, it will struggle."
Fellow exhibitor and Pershore College head of arboriculture and forestry Gareth Meadows said cost was a major issue for prospective students. "It's always changing, but right now, once you're over 19, either the company has to fund training or students self-fund. There is funding out there, but they have to search for it."
Otley College arboriculture lecturer James Firman said: "We have had funding pulled from our BTEC national diploma and national award in forestry and arboriculture, so we can't offer them, but we still provide the national certificate."
Another lecturer said: "We are limited on 19-plus training because there's no funding. Subsidised courses should be brought back, otherwise they will only be available to under-19s. Older students have a steadying effect on the younger ones."