Tackling Giant Hogweed in the Afon Soch

NRW staff member spraying Giant Hogweed

Work to eradicate an invasive and potentially harmful plant from a river on the Llyn Peninsula is showing signs of success.

Funded by Natural Resources Wales (NRW), the three-year programme aims to clear Giant Hogweed, which can be a huge problem for people and wildlife, from the Afon Soch.

A tiny amount of sap from the plant can cause skin to blister by making it very sensitive to sunlight.   

The Giant Hogweed also outcompetes and displaces native plants, which can cause river banks to erode and increase flood risk. 

A survey of the Afon Soch showed that Giant Hogweed grows along more than 2.5 kilometres (one-and-a-half miles) of the riverbanks. 

Bev Dyer, NRW Environment Officer in North West Wales said: “At the end of our second year of working with local farmers and a specialist team due to the plant’s risk to human health, we’re starting to see real improvement. 

 “Although it’s uncommon in the UK, giant hogweed is spreading rapidly along river bank and calls for concerted action if it becomes established. A single plant can produce 30 - 50,000 seeds, which can lay dormant in the soil for up to seven years. 

 “The Afon Soch does not currently meet European standards in terms of water quality. We look forward to seeing the situation improve so that wildlife can thrive and people can enjoy and benefit from our well managed river environments.” 

Originally from Southern Russia and Georgia, the Giant Hogweed was first introduced into the UK in the nineteenth century as an ornamental plant. It can spread at an alarming rate, reaching over three meters in height. 

Over the next few years, this project will continue to control the spread of Giant Hogweed, allowing natural vegetation to regrow and increase the biodiversity of our river habitats. 

The work is being carried out in partnership with Gwynedd Council’s Llŷn Area of Outstanding National Beauty (AONB) team by local contractor Adrian Moore.

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