VIDEO: Invasive plant may scupper planning permissions

Planning permission could soon be refused for houses and other buildings in areas infested by Japanese knotweed, it has been warned.

Planning is already being turned down in parts of the UK where knotweed is found, while the presence of the plant lowers the value of property, or makes it virtually unsaleable.

More than 200,000 homes in the UK have the invasive plant, which can grow through all kinds of hard surfaces, including ashphalt and concrete, undermining foundations in many cases.

The spread of the invasive plant here has been highlighted by Kerry county councillor Michael Gleeson, who has been campaigning on the issue for the past three years.

“Many people in England are terrified of knotweed and the damage it can do to their homes,” said Mr Gleeson. “The authorities there are acting and are not allowing building on land where knotweed is present. I wouldn’t be surprised to see planning refused here for the same reason in the future.”

The building of a new community hospital in Kenmare, Co Kerry, had been delayed to ensure knotweed was eradicated from the site, he added.

Mr Gleeson has also called for an education/awareness programme to ensure staff eradicating knotweed know how to deal with it properly. They should be aware that cutting the plant, actually spreads it, he said.

“Radical action is needed before this plant takes over,” said Mr Gleeson. “From my own experience, I’ve seen it grow exponentially and spread in a short period of time. It’s quite dramatic and chilling.”

Mr Gleeson said a three-year programme was needed to get rid of knotweed, with the plants to be sprayed at the same time each year, usually September/October. The roots could go down two metres into the ground.

He welcomed a decision by the National Roads Authority (NRA) to work with Galway and Kerry County Councils on a pilot programme to eradicate knotweed.

Meanwhile, all Cork County Council road staff and hedge-cutting contractors have been made aware that cutting and strimming of knotweed can lead to its spread. Some training has also been provided to all staff in operational departments.

In a report prepared for councillors, Ted O’Leary, senior executive officer at the council’s environment section, said a national approach was clearly required in relation to awareness and enforcement and the council was pursuing that with the relevant agencies.

An NRA spokesman said co-ordination of all bodies involved in dealing with non-native invasive plants and noxious weeds was needed: “The NRA is producing a comprehensive strategy that will highlight the most appropriate and effective eradication treatment of Japanese knotweed, gunnera and common ragwort.”

They would share the results of the Kerry and Galway pilot programmes directly with other national and local stakeholders.