Physical barriers remain in place around a dangerous invasive plant along a popular walking route after it was sprayed.

A large Giant Hogweed plant, which if touched can cause serious blistering, was reported to the Canal & Rivers Trust on the Grand Union Canal towpath near Apsley Lock over the weekend.

It was quickly taped off by the trust’s teams while contractors were called to remove it.

Watford Observer: The Giant Hogweed, before it was sprayed.The Giant Hogweed, before it was sprayed. (Image: Contribution)

This afternoon (June 5) a spokesperson confirmed that the specialists sprayed the hogweed yesterday and it is expected to take “a couple of weeks to die back”.

The tape will remain in place during the process and members of the public are advised not to touch it. The plant's sap can cause burns which make skin extremely sensitive to sunlight, blistering "badly" if exposed to it, according to the Woodland Trust.

The plant is thought to be an isolated example and there have not been other reports in the area, but the trust urged that any future sightings should be “reported promptly to our customer service colleagues”.

The species has exceptionally high seed production and germination rates, meaning it can spread rapidly along riverbanks as seeds can be transported via water.