Bites produce an itching sensation usually causing a skin rash.
When swarming in enormous numbers, they annoy people by getting in their eyes, nose, mouth and clothes. Many enter the home from fields and neighborhood yards. These plant-feeding pests are attracted to potted plants with excess water in their drainage pans, hitchhike indoors on cut flowers, occur near swimming pools, ornamental waterfalls, grassy areas, etc. The wing margins are fringed with close-set long hairs. Wings are laid back over the body while at rest.