Japanese Knotweed in Yorkshire: Sheffield, Rotherham and Leeds named in expert heatmap - do you know how to spot it?
A new report from a leading specialist in the treatment and removal of Japanese Knotweed has identified more than a thousand instances of the invasive plant across Yorkshire, including in York, Hull, Doncaster and Bradford.
Japanese knotweed first arrived in UK in the Victorian times in a box of plant specimens delivered to Kew Gardens and was quickly adopted by gardeners and horticulturalists, who were unaware of its invasive nature. Since then it has spread widely, with an average of 1.1 occurrences in every square mile of England.
It tends to emerge in springtime, growing rapidly into bushy, lush shrubs with pink-flecked stems. Its leaves are heart-shaped and its notoriously strong canes resemble that of bamboo. Its underground rhizomes burrow up to 3m below the surface, and have been known to shoot around 7m sideways, penetrating anything and everything in its path.
There are many well-documented incidents where homes and property have been damaged by Japanese Knotweed, though mortgage lenders usually insist checks for it are made and interventions triggered where necessary as and when a property changes hands. A Defra report in 2023 put the cost of tackling Japanese Knotweed to the UK economy at £250m.
Japanese Knotweed: where is it most prevalent?
The following table was compiled by Environet, and documents the number of incidents where Japanese Knotweed has been found in Yorkshire:
- Sheffield – 618
- Rotherham – 284
- Leeds – 179
- Hull – 115
- Barnsley – 82
- Wakefield – 61
- Rawmarsh – 57
- Doncaster – 54
- Bradford – 48
- York – 45
Earlier this year, Environet launched KnotSure™, a new report for homebuyers who want to check the likelihood of a property they want to buy being affected by knotweed. It provides a risk rating ranging from High to Medium to Low, including the number of known incidences with 2.5 miles of the address and a regional ranking.
Environet owns and hosts The Japanese Knotweed Heatmap, a live interactive heatmap showing Japanese knotweed sightings across the UK.