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Blog’s interactive map helps locate poisonous giant hogweed hotspots after man suffers third-degree burns from plant

By Sophie King
02nd September 2021, a UK review site for sheds, outbuildings and gardening, has launched a live map revealing the locations of the toxic plant Heracleum mantegazzianum, more commonly known as giant hogweed. The map is crowdsourced, so the platform is looking for members of the public to submit potential sightings of the plant. Widespread infestations have already been established across the UK.

Giant hogweed is often considered the most dangerous plant in Britain due to the burning and scarring it can cause. The sap of the plant contains furocoumarins - organic chemical compounds that are toxic to humans - which seep into skin cells and prevent the skin from being able to fully protect itself from sunlight. This can lead to skin damage, notably via bad burns and scarring.
Making contact with giant hogweed isn’t pleasant. Short-term symptoms include blistering, irritation and inflammation, while long-term symptoms can involve disfiguration, purple blotches and serious scarring. The symptoms can last for months or even years after initial contact.
The map emerged following the closure of the PlantTracker app, which was created as a joint effort by the Environment Agency, Natural Resources Wales, Scottish Natural Heritage, and the Scottish Environment Protection Agency. The app could no longer function due to a lack of funding, and that’s where came in - they introduced the map to track the spread of giant hogweed throughout the United Kingdom.

You can view the map and submit sightings here:

Currently, the map shows widespread giant hogweed infestations across the entirety of the UK. The plant is most commonly sighted near canals and rivers, often along riverbanks, as its seeds are transported through rivers.
When the plant is fully grown it can reach up to five metres tall, with an overall spread of one to two metres. has shared the following pointers for identifying the plant:
Stems - green with purple blotches and white hairs. They have a thick circle of hairs at the base of each stalk. 

Leaves - very large and can span up to 1.5m wide and 3m long. The leaves are divided into smaller leaves and look similar to a rhubarb leaf, with a hairy underside. 

Flowers - appearing in June and July, these are small clusters of white flowers that face upwards. 

Seeds - approximately 1cm long and dry, oval and flattened. 
Started as a solution for a frustrated landscape gardener struggling to find the best buy, is the largest independent buyers’ guide for garden buildings, tools and resources in the UK. With sheds of all different shapes, sizes and materials, also has the largest selection of garden sheds in the UK.
Kate Fromings of said, “As gardeners and lovers of outdoor spaces, we think it’s important to take responsibility when we’re enjoying these spaces. Whether that’s by picking up litter or reporting giant hogweed sightings, we believe that this is the right thing to do and urge others to do the same.
“It’s such a shame that the previous tracking app could no longer find the funds to continue. It’s a good cause, which is why we’re hoping that the wider community can contribute. These plants are nasty and can cause injury to both humans and animals, so the sooner we track it down, the sooner we can warn others and help them to safely enjoy the great outdoors.”

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