Flower Flies

Flower flies you say? Are they another new annoying insect that just hitched a ride to Colorado on plant material from another planet? The short answer - no, flower flies aren't from Mars and they are definitely not annoying. They are abundant this summer, we sure could use their help with all the pest flying objects out there.  

Photo by Baldo Villegas

Also known as hover flies or syrphid flies, flower flies are very common in gardens and throughout all states. But most people take one look and think they are seeing a stinging wasp or bee of some kind. Nope, they're harmless, unable to sting or bite, and pretty ones at that. Flower flies are in the same family order as the ones you swat - Diptera, which in Greek means di = 2 and ptera = wings. Remember, bees have four wings.

You'll spot adults feeding or hovering on flowers, they like nectar and pollen like bees. Adult bodies are 1/4 to 3/4" long, brown or black marked with bands or dots of white or brightly colored yellow or orange on their abdomen or thorax. Their flying skills are remarkable, including flying backwards. Near plants they rapidly adjust their wings to remain in the same position (even when it is windy), so they can get to their pollen lunch. Male flying skills even impresses the lady flower flies since they do the choosing...woo hoo! 

Larvae near aphids, Photo by Baldo Villegas

Their tiny slug-like, tapered larvae (maggots) are pink, yellow, green or brown and do their best work in the garden as predators of aphids and other soft bodied prey. Adults lay their eggs near food sources - aphids, how's that for eating convenience. Encourage flower flies in your garden by keeping it pesticide free and growing lots of blooming plants.




Additional Information:

United States Department of Agriculture Forest Service - Flower Flies

Baldo Villegas - Beneficial Organisms of the Home Garden