Flora of Northern Ireland
Heracleum sphondylium ssp. sphondylium
© Angela Ross
Heracleum sphondylium ssp. sphondylium
© Angela Ross
Heracleum sphondylium ssp. sphondylium
© Angela Ross
Heracleum sphondylium ssp. sphondylium
(Map updated: March 2008)
 

Hogweed is one of the commonest of the native umbellifers, occurring as a wayside weed, a member of the woodland or hedgerow floras and as a garden weed; also in a wide variety of other habitats. It has white or pale pink flowers, followed by flattened oval fruits which have a distinctive smell when crushed. The leaves are lobed, usually with quite broad segments although a form with very narrow lobes (var. angustifolia) is quite common. The plant is biennial, perhaps rarely annual, with a stout taproot.

This species can cause inflammation when the sap contacts the skin on bright sunny days. The related giant hogweed (Heracleum mantegazzianum) has a similar, but probably more pronounced effect.

Northern Ireland plants belong to the subspecies sphondylium. The hybrid between H. sphondylium and H. mantegazzianum has been found in Northern Ireland on rare occasions.

All names: Heracleum sphondylium ssp. sphondylium