Herb

Sosnowsky's hogweed

Heracleum sosnowskyi Manden. · Polish: Barszcz Sosnowskiego

Poisonous

Photo: Krzysztof Ziarnek, Kenraiz / Wikimedia Commons, CC BY-SA 4.0

Poisonous

The sap and essential oils contain furanocoumarins, which in sunlight cause skin damage resembling burns, and even extensive skin necrosis. Symptoms appear from a few to a dozen or more hours after contact; the oils can be carried in the air near the plant. Do not touch it, especially with bare hands. After contact (GIS – Chief Sanitary Inspectorate; sanepid – state sanitary inspection): wash the skin as soon as possible with lukewarm water and soap, do not scratch, keep it cool, rinse the eyes with water, avoid sunlight for at least 48 hours; for a burn, contact a doctor, and for a severe burn or difficulty breathing, call an ambulance. The skin can remain oversensitive to UV for as long as several years. It is an invasive alien species of Union concern (on the EU list of invasive alien species since 2016; Alien Species Act (ustawa o gatunkach obcych) of 11.08.2021). If you suspect poisoning, call 112.

How to identify it

A giant plant: usually about 3 m, sometimes up to 5 m tall; leaf rosette up to 2 m across.
Thick stem (up to 12 cm), covered in purple blotches.
White flowers in a huge umbel (up to 50 cm across); usually flowers in June–July.
Looks like overgrown dill or the native garden angelica (Angelica archangelica).

Where it grows

An alien species from the Caucasus region, brought to Poland at the end of the 1950s; it spreads in places abandoned and left unused by people.

Sources

Last checked: 9 November 2026. Spotted a mistake? Write to us.