Does this look familiar?
I’ve received A LOT of questions this month about these mounds with pencil eraser-sized holes appearing in the landscape. More often than not, these mounds are created by ground-nesting bees as their “spring” activity gets underway. We don’t usually see these pop up until late February or early March but it has been a warm January and some insects are already getting a headstart on the season.
Ground-nesting bees take advantage of bare patches to create small holes and mounds at the turf surface. They are active for a few weeks and then disappear until the following year. Chemical control is generally not recommended for these insects as this group is comprised of many native bee species. To discourage adult nesting, you can ensure more surface coverage by encouraging turf growth (irrigating, fertilizing) throughout the growing season. Areas where the turf struggles due to lack of sunlight can be covered with mulch especially where the soil is exposed. Females will nest in areas of thinning mulch so be sure to fill in with an adequate amount.
My best advice is to discourage future nesting if the mounds are an eyesore. Otherwise, leave them be and let them do their thing 🙂