Q. I have little black bugs on my eggplants. What are they?
John from Liberty
A. Flea beetles. They are little black insects that jump when you disturb them. Thus, the “flea” in their name. There are several species of flea beetles, each doing damage to different crops and looking a little different. This one is most likely a potato flea beetle. I see them most often on eggplant, then some on peppers. Earlier this season, we saw them in large numbers on collards and other greens. They can overwinter in our area, but are usually knocked down in numbers by the cold weather. In southern Ohio, they are more of a problem because it is warmer. We know how bad the beetles will be by the flea beetle index. It is a measure of the average monthly temperatures in December, January and February.
Corn flea beetles seem to be the worst problem because they transmit a bacterial disease called Stewart’s Wilt to our sweet corn crops. So, farmers have to really pay attention to this insect.
For the home garden, I find that yellow sticky cards (made so the insects will be attracted, then stick to them) are very handy. They will let you know when there is a problem because lots of them will be stuck to the cards. Some university sites recommend using a “trap crop,” like radish or mustard, which are favored by the insects. They will eat that before they eat the crop you are trying to protect. They also favor the tallest, earliest crops available. So, if you’re worried, prepare by growing a couple trap crop plants. As usual, be careful when using any insecticides on your vegetable crops. Do not use a chemical that is not properly labeled for vegetables. Read and follow the label if you choose to use a chemical. For more details on the beetles, go to: http://go.osu.edu/fleabeetle.
Eric Barrett is an OSU Extension educator, Agriculture & Natural Resources, Mahoning County.