More than 15 miles of river bank and lake shore have been cleared of one of the region’s most prolific alien invaders over the last year. Himalayan balsam, a plant which spreads rapidly and can cause terrible riverbank erosion, has also been completely cleared from two tributaries of Ullswater.
The success in the fight against this invasive species is thanks to the work of an army of volunteers; 260 people have given up their spare time to help clear the plant during 2012. The clearance took place during 33 events, with volunteers contributing 1, 200 hours of hard work.
Paul Greaves, Invasive Species Officer at Eden Rivers Trust, said, “We are so grateful to all the volunteers for the fantastic contribution they have made towards ridding the Eden river system of Himalayan balsam. There is a lot more to do but we have made great strides forward this year.”
The project has been supported financially by the Environment Agency, Natural England, Cumbria Community Foundation and Cumbria County Council.
Himalayan balsam was introduced to Kew Gardens from Kashmir in 1839 and has since spread out of control across Britain. Despite its pretty appearance its presence on river banks is very unwelcome. It not only shades out native plants, stopping them from growing, but also makes the banks liable to severe erosion in the winter when the plant dies down and leaves bare sections of ground with no protection. Before dying down for the year its seeds spread over a large distance, allowing it to grow back quickly in the spring. The only ways to stop it are to pull out each plant by hand, strim the area or use a chemical spray.
A lot of work has also been carried out this year to clear the plant from large areas away from the rivers and lakes, where it has spread.
As well as Himalayan balsam steps have been taken to stop another major invader this year. Another foreign plant, Japanese knotweed, has been spreading like wildfire. It is so tough it can grow through tarmac and concrete and once again takes over entire river banks, killing off native plants. This year all the Japanese knotweed around Ullswater has been mapped and 98% of it has been treated with herbicide. In total more than 2000 square metres have received treatment in 2012.
The third unwanted visitor receiving treatment this year has been giant hogweed, an invasive plant from South West Asia. It was introduced to gardens in this country in 1828 and now grows around rivers and ponds. Although not as widespread as the others it is difficult to remove and can cause nasty burns to people who touch it. Eden Rivers Trust has been treating it with herbicides.
A poster, warning people of the dangers from “Eden’s most unwanted” has been designed and distributed to 2,500 people. Signs have also been put up at eight sites to warn boat users of the dangers of unwittingly spreading these plants and animals. These are located on the River Eden at Lazonby and around the shores of Ullswater. People are being asked to Check, Clean and Dry their boats and equipment as they leave the water. Information has also gone to four marinas and to triathlon clubs and competitors because they use wet suits.
The message about these dangers and events to deal with them have been widely publicised locally. Presentations have also been given to local community groups and colleges.
