Blistering (lat. bullae) after contact with giant hogweed in summer. The clinical presentatin is identical to second grade burns.
Heracleum mantegazzianum, commonly known as giant hogweed cartwheel-flower, giant cow parsnip, "hogsbane" or giant cow parsley, is a plant in the family Apiaceae. In New Zealand, which does not have any native members of the Apiaceae, it is also sometimes called wild parsnip, or wild rhubarb, It typically grows to heights of 2–5 m (6 ft 7 in–16 ft 5 in), sometimes reaching 7 m (23 ft). Except for size, it closely resembles common hogweed (Heracleum sphondylium), Heracleum sosnowskyi or garden angelica (Angelica archangelica). It is phototoxic and considered to be a noxious weed in many jurisdictions. Giant hogweed is native to the Caucasus Region and Central Asia. It was introduced to Britain as an ornamental in the 19th century, and it has also spread to Ireland, Finland, Sweden, Germany, France, Belgium, Czech Republic, Latvia, the United States and Canada.
The sap of giant hogweed causes phytophotodermatitis in humans, resulting in blisters, long-lasting scars, and—if it comes in contact with eyes—blindness. These serious reactions are due to the furocoumarin derivatives in the leaves, roots, stems, flowers, and seeds of the plant.
