Title: UK's National Trust launch campaign to save stately homes from alien weeds

[Telegraph - By Louise Gray 5th June, 2010] -- The UK's National Trust has launched a nationwide campaign to tackle invasive plant species which were introduced into the country to decorate the gardens of stately homes. Japanese knotweed, rhododendrons and hottentot figs were all imported in the days of the British Empire as exotic plants for aristocrat's gardens. But the plants are now out of control choking ponds, ripping up walls, threatening the health of visitors and could take over some of Britain's best-loved landscapes.



Japanese knotweed is one of the invasive species being cleared from National Trust land.

'Plant Invaders Week' will see hundreds of volunteers at properties around the country every year weeding out skunk cabbage, chopping down giant hogweed and digging up Himalayn balsalm.

As one of the UK's largest landowners, the National Trust is also hoping to set an example to ordinary gardeners and homeowners about how to deal with the growing problem of invasive species.

The most damaging plant on the rampage in Britain is Japanese knotweed. With its pretty white flowers, it was brought into the country in the 1840s from Asia as an ornamental plant, but soon took over parks and gardens. The plant can grow up to nine feet tall and rips up concrete or tarmac.

At Newark Park in Gloucestershire Japanese knotweed is destroying the ha-ha in the garden of the stately home and in nearby Sherbourne Park it is growing through the tarmac by the lake.

The plant has be to injected with herbicide before being ripped up and it would cost in excess of £1.5bn to eradicate Japanese knotweed from the UK completely. But thanks to volunteers the National Trust is managing to clear land like the Kenidjack Valley in Cornwall so the native bluebells can return.

Rhododendrons look beautiful in gardens with their exotic blossom but the trees now drown out woodland in some of the last wilderness in Britain in the Highlands and Wales. In Snowdonia the rhododendrons have buried the heather and in Brownsea Island, Dorset it threatens the red squirrel as native pines cannot grown.

Hottentot figs also look beautiful in bloom but the trees are now threatening wildflowers on the Lizard Peninsula, the most southerly point in England where the rare chough nests. National Trust tree surgeons may have to abseil down cliffs to cull the alien species.

Giant hogweed is one of the worst problems for the National Trust, as the huge plant has caustic sap that can bring people out in blisters. Along the River Tamar in Devon and Cornwall it has stopped walkers and fishermen from being able to enjoy the riverbank.

Simon Ford, National Trust Nature Conservation Adviser, admitted it took a lot of work to get rid of invasive species like New Zealand Pygmy than has to be dredged out of ponds.

He warned the problem could get worse over the next few years because of global warming.

"Invasive plants have the potential to move into a rivers and valleys smother everything else and leave little room for other plants to flourish and wildlife struggles as a result," he said.

"If we sit back and do nothing there is a real possibility that a few non-native invasive plants will survive and we will lose the beauty and diversity of our landscape. That's why we're making a commitment to have a decade of action to control non-native invasive plants and highlight the challenges that they pose to our native flora and fauna."



From http://www.telegraph.co.uk, see original source.



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Article: WeedsNews487 (permalink)
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Date: 7 June 2010; 12:25:30 PM AEST

Author Name: David Low
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