Question: Attached are photos of this little black bug that hangs out on the ground, close to my raised lettuce garden. I haven’t seen any of them on the lettuce, but they hang out on and near the shade cloth when it’s not covering the garden. I have the shade cloth lying on the ground near the garden most of the time, and that’s when I see the bugs there. They are bigger than regular ants, and smaller than carpenter ants.
Answer: These beetles are sometimes called darkling beetles. Some species are predators of other insects while others feed on decaying plants and still others feed on stored grains. It’s hard to determine the species from your photos but I suspect these are not a pest problem based on your examination of the lettuce. To be sure, you can keep an eye on the situation and notice if your plants begin to suffer any damage.
Peter L. Warren is the Forest Health Program coordinator for the Arizona Department of Forestry and Fire Management. Questions, photos and videos may be emailed to tucsongardensage@gmail.com