Giant hogweed: How to identify plant that causes burns and blisters
A warning has been issued about giant hogweed after a number of people have suffered swelling or scarring after brushing against the plant.
The giant hogweed can be found in parks and along canals and rivers in the UK, and can cause severe burns.
On Monday, the BBC reported that a 21-year-old man could be left with potentially lifelong scars after he touched giant hogweed.
Daniel Logan was stung on the ankle by the plant while retrieving a football in Boston Manor Park in Brentford, west London.
Read more: Giant hogweed has left me scarred for life, says man who suffered ball-sized blisters
"It's been terrible to be honest," Mr Logan, who suffered a severe blister to his ankle, told the BBC.
"Now I know, it will never happen again. But I'm lucky, I'm 21 years old and it's only my ankle.
"If a little kid falls in there, gets it on their face or something, that's going to cause them life-changing injuries, so I'm lucky but someone else may not be."
Earlier this month, Tina Sabine, 28, from Leamington Spa, Warwickshire, recalled how she was taken to hospital after she brushed against some giant hogweed while walking her dogs.
She said she swelled up "like a Teletubby" after coming into contact with the plant in 2021.
Ms Sabine, a graphic design student, also suffered blisters all over her right hand.
She spent a month in hospital and was unable to walk for two weeks, and had to use a mobility scooter for six months.
"I woke up and I couldn't physically move," she said. "I was in pain, not terrible just annoying pain.
"I looked at my hand, it blew up and was bright red. It looked like it had been dunked in acid. At the hospital they asked if someone had poured acid on my hand.
"My fingers swelled up, they had to cut off my rings, they're still swollen today.
"I didn't look in the mirror until the hospital and the right side of my face bulged out so much that I looked like a Teletubby.
"I'd been walking the dogs the day before so I think I must have come into contact with it there and then touched my face.
"It was blistering. I was in a lot of pain."
Ms Sabine said the severe reaction to the plant had caused a blood clot on her spine, meaning that walking became agony.
"I was in hospital for over a month," she said. "I still can't use my right hand today. I started feeling better after about two weeks.
"I've been back to the place where I suspect I came into contact with the hogweed and it's still there. It's scary to think that there are kids out playing and could touch it."
What is giant hogweed?
Also known by its botanical name, Heracleum mantegazzianum, giant hogweed is a plant in the Apiaceae family that includes parsley, carrot, parsnip, cumin and coriander.
According to the Woodland Trust, giant hogweed is not native to the UK and originates from the Caucasus Mountains between Asia and Europe, and also from Central Asia.
It was first reported in the wild in the UK in 1828 in Cambridgeshire.
The Woodland Trust said: "It is now classed as an invasive species and can be found throughout much of the UK, especially colonising river banks where its seeds are transported by the water."
Giant hogweed resembles a large cow parsley plant and can reach heights of between 1.5m and 5m.
Its stems are green with purple blotches and white, bristly hairs.
Its flowers appear in June and July and are small and white, or sometimes slightly pink, and form umbrella-like heads.
How can giant hogweed be harmful?
The Woodland Trust says the sap from the giant hogweed can cause burns.
It contains furocoumarin, which makes skin extremely sensitive to sunlight.
The Woodland Trust said: "If the sap gets onto your skin and it's then exposed to the sun, your skin can blister badly.
"Blistering can then recur over months and even years. This is known as phytotoxicity."
It says the best way to avoid injury is to familiarise yourself with the plant and avoid skin contact.
What should you do if you touch giant hogweed?
The Woodland Trust says: "If you do get giant hogweed sap on your skin, be sure to wash the area thoroughly and immediately.
"Seek medical advice and do not expose the area to sunlight for a few days."