Three county project to stem spread of Japanese knotweed (From Daily Echo)

Three county project to stem spread of Japanese knotweed

A NEW three-county project will try to stem the spread of non-native invasive plants throughout the Hampshire Avon and its tributaries to protect the future of their native wildlife.

Wiltshire Wildlife Trust has joined forces with Hampshire and Isle of Wight Wildlife Trust and Dorset Wildlife Trust to get rid of plants such as Himalayan balsam, Japanese knotweed and giant hogweed among others that threaten to overwhelm native wildlife in the waters and on the banks of this internationally important river catchment.

Called Source to Sea, the project has received substantial backing from the Environment Agency.

The Avon rises in the Vale of Pewsey in Wiltshire and passes through Hampshire at the edge of the New Forest before flowing into the sea at Christchurch in Dorset, which is why an integrated approach across county boundaries is crucial to its success.

Its tributaries include the River Bourne which runs through the Collingbourne, Tidworth, Shipton Bellinger and joins the Avon near Salisbury.

Sam Stork, Source to Sea project manager at Wiltshire Wildlife Trust said: "The Salisbury Avon and tributaries such as the Nadder and Wylye are magical waterways recognised for their magnificent wildlife by being designated as Sites of Special Scientific Interest and Special Area of Conservation.

“Non-native invasive plants could threaten the survival of their water voles and otters, Atlantic salmon, brown trout and lamprey if we stand by and do nothing while these plants steadily suffocate the banks.

"For the project to succeed we will need lots of volunteers to help us pull up the balsam, and we will need the help and support of riverside landowners to either remove the plants or allow access for our volunteers to remove them," said Sam.

Joanne Gore, Field Officer for the Hampshire and Isle of Wight Wildlife Trust said: "I am very happy to be working with my colleagues in Wiltshire and Dorset to tackle non native plants on this internationally important river catchment.

Tackling the problem from source to sea will ensure that the project can look to effectively control the devastation caused by non native species. Nothing on this scale has been tried before."

Joanne has already begun working in the Hampshire Avon valley, supporting landowners who have non-native plants on their land.

"I have been delighted by the response of landowners on the river catchment. They have been very willing for me to survey their sections of the river catchment and have allowed me to organise contractors and volunteers to help remove non native plants, like balsam, where they have been found."

Himalayan balsam is an annual plant that grows into bankside thickets, crowding out all native wildlife. Then when the stalks die back in winter it leaves bare river banks that are vulnerable to soil erosion.

The key to its control is to pull the plants up while it is flowering and before it releases it seeds, because if these get into a water system they very quickly spread and can colonise areas downstream.

Japanese knotweed and giant hogweed cannot be tackled by the public – only by someone who has gained a certificate in herbicide application.

Source to Sea builds on previous work done in Wiltshire to control non-native invasive plant species in the county, targeting hotspots of non-native plants on the Avon and other rivers, but never has a whole catchment programme been attempted before.

If you are a land owner on the River Avon catchment and would like further advice on non-native invasive plants or would like to volunteer for the project to help carry out surveys or practical work this summer, call Sam Stork on 01380 736066 or email sams@wiltshirewildlife.org.