Control of Hydrocotyle ranunculoides


In the UK, floating pennywort Hydrocotyle ranunculoides, native to North America, is a highly invasive, very fast growing aquatic plant. It was introduced into the UK via the aquatic nursery trade and was first noted growing in the wild in 1991. It is now present at over 30 sites, mostly in southern England. One of the most severe infestations occurs on the Pevensey Levels in East Sussex, where very dense floating mats have caused serious flooding and loss of livestock. Experimental control using herbicides and mechanical methods were trialed.

Study area: The Centre for Aquatic Plant Management started an experimental treatment programme in 1998 to control H.ranunculoides on the Pevensey Levels in East Sussex, southeast England. The eventual aim was to eradicate the plant from the site.

Treatments: Treatment involved the application of the herbicides, 2,4-D amine and glyphosate, and some mechanical methods.

The treatment proved to be unsuccessful and alternative methods are now being implemented at this site. Additional research is being carried out into the use of alternative herbicides to control H.ranunculoides colonies in Britain.

Note: If using or referring to this published study, please read and quote the original paper, this can be viewed at:

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