Today Rivers Trusts in North East Wales are holding a conference on the Management of Invasive Weeds in the River Dee catchment at Beaufort Park near Mold.
The Trusts are co-operating on a major programme to eradicate invasive weeds from three rivers catchments, the Dee, the Clwyd and the Conwy.
The project concentrates on three weeds in particular, Japanese Knotweed, Himalayan Balsam and Giant Hogweed. Left untreated, these species can spread at an alarming rate, smothering native wildlife.
Spraying invasive plant species. Image by Rivers Trusts of North East Wales
The Balsam and Knotweed for example, shade out the native wild flowers and insects that depend on them, which leaves the ground bare in winter leading to erosion of these areas.
"One of the main aims of the River Trusts is to maintain and enhance native species of plants and animals in their catchment areas," says Dr Neil Smith from the Countryside Council for Wales (CCW).
"The project is challenging, owing to the large size of the catchment. We hope the conference will help all the groups involved work well together and make steady progress in years to come."
The conference is sponsored by the Countryside Council for Wales, Environment Agency Wales, Natural England and the local authorities within the catchment and is calling for a systematic approach and good training to tackle invasive species.
Richard Lucas of the Welsh Dee Trust said: "So far we have trained 28 volunteers who are accredited in the use of herbicides near water systems, but we hope this conference will enable us to share ideas of best practice and get many more involved."
Another part of the work involves the long-term mapping of the invasive weeds to provide better information for management and control.