Crassula helmsii (New Zealand pygmy weed) on Derwentwater in the English Lake District. The view is from the lake's southern edge looking north. The d

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Crassula helmsii (New Zealand pygmy weed) on Derwentwater in the English Lake District. The view is from the lake's southern edge looking north. The distant left-hand peak at the top is Skiddaw. The foreground shows an infestation of C helmsii (yellow/green). The plant is floating on the water, extending out from the shore at the left hand edge of the picture for more than 10 metres, and beyond (upper, right) into open water. The bright green bracken (Pteridium aquilinum) seen to top left edge marks permanent dry land. is an increasing environmental hazard to freshwater systems in the UK. Difficult to control, it can propagate itself from small detached fragments carried away by boats or footwear or birds. It is banned from sale in the UK and is covered by Schedule 9 of the Wildlife and Countryside Act 1981, making causing it to grow in the wild an criminal offence

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Size: 3468px × 5212px
Photo credit: © DR JEREMY BURGESS/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: 9, alien, crassula, derwentwater, distrct, environmental, freshwater, hazard, helmsii, introduced, lake, national, park, pest, plant, pygmy, schedule, scheduled, system, weed, zealand