Bridgend County Borough Council is offering advice to local residents about how to treat problem plant Japanese knotweed. Often found growing in gardens, along rivers, woodlands and even in car parks, this invasive plant forms thick, dense colonies that completely crowd out any other herbaceous species. Care should be taken when dealing with Japanese knotweed. It is a criminal offence to cause it to spread, and very small fragments of shoot or root material can give rise to a new infestation. It is the duty of the landowner to treat Japanese knotweed on their land if it is growing onto neighbouring land. The council has joined forces with organisations such as the Llynfi Rivercare Group, Environment Agency Wales and Keep Wales Tidy to offer the following advice to anyone who discovers a small infestation in their garden. Japanese knotweed is classed as controlled waste under the Environmental Protection Act (1990) and can only be disposed of at a licensed tip, with a licence from the Environment Agency Wales. If you intend to manage Japanese knotweed without the use of herbicides, please contact the Environment Agency Wales for advice. NEVER place cuttings of Japanese knotweed into compost. NEVER dispose of Japanese knotweed as green waste. You should spray Japanese knotweed with herbicide at the end of the growing season, just before the plant dies back in early September. Spraying should be carried out in calm, dry conditions, when no rain is expected for 24 hours after spraying. Herbicide treatment earlier in the season will not be effective. A follow up spray may be required in subsequent years to kill off the remaining shoots. If you are spraying within 10 metres of a water-course, approval is required from the Environment Agency Wales. Glyphosate is a chemical commonly used to treat knotweed which can be found in certain herbicides. Care should be taking when spraying with glyphosate as it will kill any plant that it comes into contact with. If you are treating an area near water, only use products which are specially formulated for an aquatic environment. Anyone who discovers a larger infestation of Japanese knotweed will need to seek professional advice by calling Bridgend County Borough Council on 01656 643160, or Environment Agency Wales on 08708 506 506.