While there are multiple species of yellowjackets, all are dangerous and send hundreds of thousands of people to the emergency room every year with allergic reactions to their stings. Much like hornets they can be found in a multitude of places, with their nests being made also of paper materials, and will try to build their nests in dark and safe places such as overhangs, caves, and attics. These nests can house up to thousands of yellowjackets and larger nests may even contain multiple queens. They will grow to be between half and inch and an inch long, and are often mistaken for honeybees and hornets. They are known to feed on both sweets and proteins, so it is very common to see them at outdoor events where those things are in high supply.