Danger to human health
Unlike Japanese Knotweed, Giant Hogweed will not damage property but is a threat to human health. Extreme caution must be exercised when coming into contact with this plant.
The stem and leaf stalks contain a sap that is released by handling, cutting or just brushing against the plant. The sap contains “psoralens” that photosensitise the skin so that exposure to sunlight results in very painful blistering, sometimes requiring hospital treatment.
If your eyes come into contact with the sap, this can cause blindness. The burning effects can last three years or more and tissue scarring can last more than 15 years in extreme cases.
Do not touch
If you have Giant Hogweed on your property, do not attempt to strim, slash, dig out, walk amongst, pick or remove it without full protective clothing. Fence off any infestation with clear warning signs, if possible.
Each hogweed plant is capable of producing about 50,000 seeds and, although they only drop close to the plant, they can be carried elsewhere on the soles of people’s shoes. The seeds can remain viable for 5 years, meaning that total eradication is a long and expensive process. However, a reasonable measure of control can be achieved quickly by removing the seed heads and treating the plant regularly with herbicides.
If you think you may have Giant Hogweed on your land, book an appointment for a free site visit and we can give you a quote for a treatment programme.