Wild parsnip could become the latest dangerous invasive plant to spread through the country unless urgent action is taken, BALI's technical director has warned.
The plant, a relative of Japanese knotweed, has been spotted in Kent and Sussex and is dangerous to humans. Its roots are edible but its sap causes skin blistering and burning, even through clothes.
Neil Huck, who is also national group training manager at Ground Control, said: "People cutting it down find it goes through their trousers and into their skin. It's very minor at the minute but as it develops it could become a big problem."
Wild parsnip, which is from southern Europe, has also spread across the US and Canada after being introduced by European settlers.
Huck said it spreads through seeds, which are light and could easily arrive in the UK on other plants.
It is a biennial and the seeds die down in the second year.
He said: "I think biosecurity is a big issue and the industry needs to wake up a bit about imported plants."
Huck called for better education among the public, growers, nurseries and landscapers.
Ragwort, which can kill horses if ingested, is also an increasing problem. Both the British Horse Society and the RSPCA say public concern about the weed has risen.
"There's a lot more ragwort at the moment because people like the Highways Agency have no budget to cut it," he said.
Highways Agency - Tackling invasive plants
The Highways Agency spends around £200m per year on combined road and verge maintenance contracts, which can help remove invasive plants. Last year it introduced new contracts which are expected to deliver substantial savings.
A representative said: "We can no longer afford to always deliver services in the same way as in the past. This will inevitably mean there will be a less visible presence on the network. It is important to emphasise that better value is what we are looking for, not reductions in network maintenance."