This time of year the highways and byways of much of the United States is abloom with wild carrot, also known commonly as bird nest, Bishop’s lace or most commonly as a naturalized form here in the United States, Queen Anne’s Lace.
It grows as an erect biennial in full sun frequently growing up to a meter or more tall. The flower head starts out as a bunched up clump of flowerlets with a tulip like shape. As the flower matures it opens up to form a saucer like shape of many small white flowers.
Its formal name is Daucus carota and is a member of the Apiaceae family (also called Umbelliferae family) which includes several other domesticated plants such as celery, parsnips, and parsley. The root of the wild carrot can be eaten when young but as it gets older it becomes to woody.
All members of this family can cause phytophotodermatitis. In a sensitive individual, contact with the leaves of the plant can cause redness, irritation and even blisters, but only after exposure to the sun. Apparently the oleoresins (plant oils) are absorbed into the skin. There a chemical reaction occurs with proteins. When the modified protein is exposed to the sun, it causes a classic dermatitis reaction not unlike exposure to poison ivy. Other plants that cause this type of skin irritation include Celery and unrelated citrus fruits.
It is not uncommon for agricultural workers handling a lot of produce to be effected. Grocers, chefs and even bartenders can be affected. An evening of mixing up bloody marys and shots of tequila followed by a day in the sun can result in irritated skin due to contact with celery and limes.