Collected on this Day in 2001
Giant hogweed (Heracleum mantegazzianum) is considered a significant public human health concern. This non-woody plant can be 8–20 feet tall with leaves up to 5 feet wide!
In fact, it took six separate herbarium sheets to capture the characteristics of this species. This specimen was collected from a garden, where it was intentionally grown for the purposes of educating the public about this plant. Native to central and southwest Asia, this plant can now be found in parts of Europe, Australia, New Zealand, and North America. It is thought to be eradicated in Pennsylvania.
This plant is highly poisonous and designated as a federal noxious weed. The sap of giant hogweed causes “phytophotodermatitis,” meaning serious skin inflammation occurs when contacted skin is exposed to sunlight. Skin rashes can be very severe. The sap is also said to cause blindness.
Giant hogweed, like poison hemlock and Queen Anne’s lace, is in the carrot family (Apiaceae). It might be confused with the related native plant, cow parsnip (Heracleum lanatum), but giant hogweed is noticeably larger in height and flower size.
Botanists at Carnegie Museum of Natural History share pieces of the herbarium’s historical hidden collection on the dates they were discovered or collected. Check back for more!