A national trade body is being vigilant to the spread of a new type of invasive non-native plant.

The Property Care Association (PCA) says reports of a Japanese knotweed hybrid, ‘Bohemian knotweed,’ are on the increase.

Also known as Hybrid knotweed, the plant is produced by cross fertilisation between Japanese knotweed and Giant knotweed.

According to Dr Peter Fitzsimons, Group Technical Manager of the PCA’s Invasive Weed Control Group, this knotweed could be a real concern if it gains a foothold nationally.

Dr Fitzsimons said: “Bohemian knotweed, although less common, has been around for almost as long as the better-known Japanese knotweed, but is not always recognised.

“As a result, it has remained largely below the radar, but the reason for concern is that these hybrid plants can be even more vigorous than the parent plants.

“We also need to be alert as, in other parts of the world where Hybrid knotweed is more common, they are seeing signs of fertile seed production, known as back crossing.

“If so, this could be a major concern for the future as the existence of seed producing hybrid knotweeds may enable these plants to spread even more rapidly.”

Japanese, Giant and Hybrid knotweed are all listed under Schedule 9 of the Wildlife and Countryside Act.

Dr Fitzsimons added: “Japanese, and other closely related knotweeds, are nuisance plants because they spread easily via their rhizome network, grow rapidly and are capable of causing disruption around buildings.

“Since the PCA formed the Invasive Weed Control Group in 2012, we’ve always maintained the position that whilst this plant is disruptive around buildings it can be brought under control using established techniques and processes.

“However, its presence can impact on the ability to gain a mortgage and on the development cost of land.

“More research is needed to see what the impact is of Bohemian knotweed, but for now we should be aware of the issue.

“If anyone has concerns about this or any type of invasive, non-native weed, PCA’s Invasive Weed Control members can advise on identification and the necessary treatment.”