Hi, I have small holes in my lawn, no mound of soil, just clean holes, of varying sizes. What could it be?
Hi Kay, the holes could be caused by soil insect pests such as grass grub, porina moth, bronze beetle, sod web worm or army worm. All cause damage to grass and some damage ornamental plants. If there are dead patches in the lawn with small tunnels and dead grass then dig down to a spade depth and you are likely to find grass grub larvae which feed on grass roots. If the area of lawn around the tunnels has no grass just bare patches, then it could be porina moth larvae, they emerge at night and feed on the grass. Bronze beetle emerge at night and feed on leaves of plants, which will have a shot hole appearance, sometimes they can do a lot of damage to leaves, the larvae feed on plant roots before they emerge as beetles. Sod web worm and army worm look like caterpillars, they feed on grass, sod web worm feeds at night, army worm feeds during the day. All can be controlled at the larvae stage using a soil insect control product, your local garden centre will be able to suggest a suitable product, but synthetic pyrethroids such as Bifenthrin are effective, you could try Diatomaceous Earth, a silica based product that is like crawling over cut glass for caterpillars, Neem granules may also be effective. Spring and autumn are a good time to treat soil insect pests as in winter and summer they tend to go deeper into the soil. It is difficult to control these lawn insect pests once they are at the beetle stage. Lianne