An Invasion of Flea Beetles by Donna Duffy

Flea Beetle - photo courtesy CSU Extension

I was working in the yard this morning and noticed an abundance of tiny, shiny, jumpy insects. After some research, I discovered that they were flea beetles. Once I identified them, I started seeing them in my neighbor’s yards as well. So I turned to CSU Extension and discovered Fact Sheet 5.592: Flea Beetles.

Here are a few quick facts about flea beetles:

• Flea beetles are small beetles that jump when disturbed
• They damage plants by chewing small "shotholes" in the foliage.
• Flea beetles can be found on a wide variety of plants. However, most flea beetles attack only a few, closely related plant species.
• Flea beetle injury is most important when seedlings are becoming established or in the production of leafy vegetable. Injuries are usually minor and easily outgrown on established plants.

Flea beetles are common pests of many vegetable crops. They occasionally damage flowers, shrubs and even trees. Adult beetles, which produce most plant injuries, are typically small, often shiny, and have large rear legs that allow them to jump like a flea when disturbed.

Photo courtesy extension.unm.edu

Flea beetles produce a characteristic injury known as "shotholing." The adults chew many small holes or pits in the leaves, which make them look as if they have been damaged by fine buckshot. Young plants and seedlings are particularly susceptible. Although flea beetles are common, injuries often are insignificant to plant health. On established plants, 10 to 20 percent or more of the leaf area must be destroyed before there is any effect on yields.

There are several ways to control flea beetles, including:

• Cultural controls – such as using “trap crops” to attract flea beetles away from the main crop;
• Mechanical/physical controls – such as floating row covers or other types of screening;
• Chemical controls.

Apple flea beetles - photo courtesy CSU Extension

Check out the Fact Sheet for a chart that describes common flea beetles in Colorado and their host plants, as well as more information about managing (or ignoring) the little pests.