Giant hogweed is a highly invasive and toxic plant which reproduces entirely by seed. It can harm both humans and animals.
Hogweed
What is hogweed?
Giant hogweed is a highly invasive and toxic plant. The sap of giant hogweed contains a toxic chemical which sensitises the skin and leads to severe blistering when exposed to sunlight. The exposed skin can remain sensitive to light for many years after contact. The plant reproduces entirely by seed.
Hogweed bloom
Hogweed bloom
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Hogweed bloom
Hogweed bloom
Biology
Hogweed is highly toxic
It sensitises the skin and leads to severe blistering when exposed to sunlight
Plants can reproduce ueasily by seed
How can I identify hogweed?
Hogweed has large leaves which can grow up to 1m in size, leaves are deeply divided. The flower-head is flat and is made up of many small white/pink florets.
Plants can grow up to 5 metres tall; with thick hollow stems, that can grow to 10cm across and contain bristles.
Flowering plant
Rosette stage
Closer look at leaves
Why do I need to control hogweed?
- Giant hogweed is covered by the Wildlife and Countryside Act 1981. It is listed under Schedule 9 of the Act and Section 14 of the Act states that it is an offence to allow the plant to spread into the wild so needs to be controlled.
- Giant hogweed sap contains toxic chemicals which causes skin sensitivity, burns and blisters on the skin.
- It can harm both humans and animals.
Optimal control timings for hogweed
A targeted herbicide application is the only way to really control hogweed for good.
The best time to apply a herbicide is in the autumn, then the plant will take the herbicide down into its roots as the plant naturally senesces going into the winter.
Cultural solutions
Cutting the plant back will manage the population but if it is not killed it will just force the plants energy into rooting deeper.
Product choice
Grazon Pro is the most effective herbicide for the control of Hogweed. The optimum time to apply is in the autumn before the plant senesces so the herbicide gets taken down to the roots.
Grazon Pro Herbicide
Grazon® Pro is fast acting and controls a wide spectrum of weeds by moving to the roots and ensuring high levels of long-term control.