Ramblers and gardeners warned to beware of toxic giant hogweed

PARENTS are being urged to keep their children away from giant hogweed, an invasive plant with toxic sap that can cause skin burns and blisters.

The plant, a member of the carrot family, looks similar to some native species such as cow parsley, with its clusters of white flowers.

The Property Care Association (PCA) has urged caution as hot weather brings more people outdoors. “The mix of warm weather and rain has provided good conditions for the weed to take hold this year,” said Dr Peter Fitzsimons, of the PCA’S invasive weed control group.

John David, of the Royal Horticultural Society, said the sap burns are due to chemicals called furocoumarins which trigger a process called phytophotodermatitis.

The chemicals seep into skin cells and are activated by ultraviolet rays, such as those from the sun. This leads to cell death and blistering. However, the sap is stored in hollow stems that must be broken with some force for the hazardous chemicals to be released.

Experts advise caution when trampling through heavy vegetation or strimming overgrowth. “If you get the juice on your skin it can cause burns so bad you may need to go to hospital,” Mr David said, adding that children have had severe facial burns after using the hollow stems as blowpipes.

Giant hogweed was brought from western Russia, Georgia and Ukraine to the UK by the Victorians as a hardy garden plant. It then escaped and took root in unattended common land. It thrives in open, damp areas, particularly near rivers. It is tough and hard to eradicate and its seeds are spread by water.

Nic Seals, the MD of Environet, a company that specialises in invasive plants, said giant hogweed is the third most troublesome invasive plant in the UK after the notorious Japanese knotweed and bamboo.