More than 325 sites in Leicester have been blighted by Japanese knotweed – the notorious plant from Asia which damages the surrounding area wherever it appears.
The invasive species is resistant to most common methods of control and it can even damage structures it grows close to.
A spokesperson for Leicester City Council said: “We have either mapped or had reports of around 325 sites across the city where Japanese knotweed is a problem.
“We treat it but it can take years to eradicate completely, it’s impossible to guarantee eradication, so we map locations where we know it's a problem and revisit to manage it. We go out and inspect regularly.
“Cost of eradication is very variable and so are success rates. A field is easy, a brook environment more difficult, infested land with multiple boundaries and owners is very difficult. The area covered also greatly affects cost.”
Japanese knotweed was first noted in the 1900 in London and has since spread rapidly throughout Britain.
It caused such an issue that in 1981 the Wildlife and Country Act made it an offence to introduce it into wild spaces.
The plant creates a massive root system which can extend for yards outwards and downwards.
This can cause issues for the foundations of any building it is near.
Alan D'albe, trees and woodlands manager for the city council, said: "Japanese knotweed was originally brought to the UK as an ornamental specimen, but it's highly invasive because it can re-root quickly from a tiny bit of stem. You often see it along riverbanks because the river carries it easily from place to place.
"It can come up through Tarmac, concrete and even the inside of houses.
"Anyone with concerns about knotweed should contact the team by ringing our environment line on 454 1001. We record all sightings."
The city council's trees and woodlands team are trained to inject a specialist treatment into the stem of Japanese knotweed to kill it.
This is done on all council-owned sites where knotweed is discovered.
However, for private sites a different procedure is in place.
The council inform the owner that they have a knotweed problem that needs addressing.
It then asks them to work with them to tackle the problem.
Then if it is not dealt with it can issue a notice through the city warden team to enforce that the issue is resolved.