Certain native and invasive species produce a photo-toxic sap containing furanocoumarins within their stems and leaves. This chemical makes the skin more vulnerable to ultraviolet light, causing hyper sunlight sensitivity (phytophotodermatitus), severe burns and blistering, skin discoloration, and in some cases it can cause blindness if it gets into the eye. Others can be highly toxic if ingested by humans or animals. If you ingest any toxic plants, seek immediate medical help. If you are working around these photo-toxic plants, wear gloves, long-sleeved shirts, pants, boots, and eye protection to avoid coming into contact with the sap. If you do come into contact with their sap, immedi
Giant Hogweed (Heracleum mantegazzianum) is a federally listed noxious weed, as well as a phototoxic one. Its sap, in combination with moisture and sunlight, can cause severe skin irritation, painful blistering, permanent scarring, and if it comes in contact with the eyes, severe irritation and possible blindness. Contact between the skin and the sap of this plant occurs either through brushing against the bristles on the stem or breaking the stem or leaves. What does it look like? It is a biennial or perennial herb in the carrot family (Apiaceae) which can grow to 14 feet or more. It has hollow, rigid stems that grow 2-4 inches in diameter and dark reddish-purple blotches. The large compo
