Conservation volunteers are embarking on a mass clean-up of invasive alien plants on National Trust land. The organisation says this is the biggest such exercise ever conducted in the UK.
Several hundred volunteers will be involved at 75 properties around the UK. Simon Ford, the Trust's nature conservation adviser, says the operation is a Trust commitment to the International Year of Biodiversity.
Some of the invasive plants, such as Himalayan balsam, are attractive in themselves. However, they can take over big tracts of land, smothering other native species as they spread.
Japanese knotweed (left) is a pernicious invader. Its removal from a seven-mile tract of land in Cornwall's Cot Valley allowed a huge range of flowers such as marsh marigolds, bluebells and kidney vetch to bloom anew.
Last year, Simon Ford's team cleared a pond at Corfe Castle of Australian swamp stonecrop, a particularly tough specimen that spreads across the water surface like a giant sponge.
The pond had been an important amphibian habitat. With the stonecrop's removal, species such as the smooth newt were able to move back in.
Plant Invaders Week runs until next Saturday. "If things go well, we're hoping to adopt a plan of eradicating some invasives from all National Trust properties by 2020," says Simon Ford.
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