Giant Hogweed

Safety Alert Giant Hogweed



Introduced by the Victorians this relation of Cow Parsley can grow up to 5m tall and is common on wasteland and riverbanks. The sap it produces reacts with sunlight on skin causing severe chemical burns and blistering even years after contact. The harmful effects may not be noticed for some considerable time during contact increasing the likelihood of greater contact to the toxic sap.

Giant Hogweed can be confused with Hogweed when its growth is stunted. Children often use the stems for pea shooters which lead to hand/facial blistering however exposure and subsequent burns can be sustained by merely brushing past the leaves or handling contaminated clothes.

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TREATMENT - If you come into contact with the sap IMMEDIATELY wash the affected area with copious amounts of water and soap then cover. Seek medical advice.



Learn to recognise Giant Hogweed and teach children of its dangers

Avoid and isolate areas with Giant Hogweed present

Assume Hogweed could be stunted Giant Hogweed

DO NOT attempt to remove Giant Hogweed as this is an operation that requires specialist protection instead ISOLATE and REPORT to the Landowner.

Giant Hogweed and the law

It is illegal to plant Giant Hogweed in the wild potentially leading to a fine and up to 2 years imprisonment however there is no legal obligation for a landowner to remove it under law that controls the spread of invasive species.

However, land owners are required to provide a duty of care to those on their land including trespassers. Any injury resulting from Giant Hogweed could result in criminal or civil proceedings against the land owner.

PICTURES Chemical burns sustained by exposure to Giant Hogweed. These will reoccur to varying degrees for years with exposure to sunlight.

SAFETY Giant Hogweed



I've seen quite a lot of what looks like Giant Hogweed recently particularly near the Green Dragon Inn in Lymm but it appears to be all over the place especially near rivers. This coupled with recent media attention about Giant Hogweed has really got me confused.

You'd think Giant Hogweed would have the highest status with regards to the law but there are worse offenders but none seem as insidious as Giant Hogweed. Firstly it resembles hogweed and cow parsley both comparatively benign. Giant Hogweed sap however causes severe chemical burns but not straight away - it takes exposure to light to cause the activation of the sap so that children can play among it and continue to come into contact with the poisonous sap. Its only later that they develop serious blistering. Even just brushing past it or handling contaminated clothing is enough to be burned and at the time you may not even notice.

The plant also produces 1,000s of seeds so it requires year on year treatment and takes over riverbanks so ecologically wise is pretty bad. And yet its not illegal to have this on your land only to plant. This means you have areas full of Giant Hogweed where land owners aren't aware or don't care or can't afford to have it managed. The Giant Hogweed takes over, the seeds spread enter a water course and drift to other areas.

I believe it should be illegal not only to plant but also to fail to have a management strategy on your land for Giant Hogweed. Subsidies should be in place to help land owners have this professionally removed (it takes specialists to remove it safely and disposing the waste produced has legal implications). Each water course needs an effective overarching strategy to ensure there are no secret Giant Hogweed havens producing seeds which then enter the river.

Until then children (who are  affected the most) and others will have to rely on awareness to protect them so please feel free to pass on our safety post which follows this.

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