Work to remove rhododendrons which are growing out of control near a north Wales village could take 25 years and £5m to complete.
Rhododendrons may be pretty, but they are rapid growers
The invasive evergreen plant was introduced to the Beddgelert area in the19th century by fashion-conscious gardeners seduced by its striking cerise flowers.
But the shrub soon outgrew its welcome, spreading rapidly and forcing out native species .The plant quickly produces dense thickets, below which little else can survive.
It is now a common sight in woodland across the UK, and can also colonize and swamp valuable heath and grassland areas habitats.
The flowers of Rhododendron ponticum are an impressive sight on the hillsides around Beddgelert in spring.
But botanical experts have revealed that the colourful display hides a biological desert.
Like that other notorious Victorian import, Japanese knotweed, the rhododendron speads quickly, and stops anything else from growing as it shade the ground below it and sucks up vital nutrients.
It covers huge areas of hillside above Beddgelert, and has now started to spread onto more mountainous areas.
A group called the Beddgelert Rhododendron Ponticum Management Group has tried to find ways of using the plants to raise money, but so far their efforts have been in vain.
The group estimates it will cost £5m to remove the rhododendrons, but says grants for the whole amount will be almost impossible to find.
It is urging landowners to take the initiative, but admits there's a long fight ahead.