Giant hogweed has
been introduced to Europe, the United Kingdom, Canada, and the
United States as a garden curiosity.
Because of its
tenacious and invasive nature it soon becomes a pest within the
ornamental garden and readily escapes. It has naturalized in many of
the places where it was first introduced.
Giant hogweed
is a member of the parsley or carrot family, Apiaceae (Umbelliferae).
As its name indicates, it is characterized by its size and may
grow 15 to 20 feet tall. The stem and stalks are hollow. Stems
vary from two to four inches in diameter. The compound leaves
of giant hogweed may expand to five feet in breadth. Each
leaflet is deeply incised. Giant hogweed is a perennial with
tuberous root stalks which form perennating buds each year.
The inflorescence is a broad flat-topped umbel composed of
many small white florets. Each inflorescence may attain a
diameter of two and a half feet.
The plant exudes a clear
watery sap which sensitizes the skin to ultraviolet radiation.
This can result in severe burns to the affected areas
resulting in severe blistering and painful dermatitis. These
blisters can develop into purplish or blackened scars.
Proliferating populations in urban and suburban areas
represents an increasing public health hazard.
Keep the plant mowed
down during the summer to prevent seeds from maturing. Don't
allow pieces of it to land on bare skin. Even after the parent
plant is completely removed, the seeds left behind can come
up, 7 or 8 years later. Removing the green growth will help to
exhaust the root and will weaken the plant, so digging it out
and chopping it is feasible.
Giant
Hogweed is a foreign invader that prevents native plant
species from growing. Under the Wildlife &
Countryside Act 1981 / Wildlife (Northern Ireland) Order
1985 it is an offence to ‘plant or otherwise cause
Giant Hogweed to grow’ in the wild. This
includes spreading the species or transferring polluted
ground material from one area to another.
Any
Giant Hogweed polluted soil or plant material that you
discard, intend to discard or are required to discard is
classed as controlled waste and should be accompanied by
appropriate Waste Transfer documentation.
