A flock of crows on the lawn or animals rolling back sections like the lawn is carpet. Grub damage in the shows up as brownish areas that are often attacked by animals who feed on the grubs. Grubs can be reduced by an application in the spring with a material that will be in the plants root system to kill any eggs that hatch in the summer and start to feed on the root zone. In the photo to the left the lawn on the left whose property line is in front of the white picket fence has been protected by a June treatment with Acelepryn. The lawn on the right was not and was treated with a curative treatment now.
You can see the distinct line along the edge of the treated area. Preventative treatments are much longer lasting and lower toxicity when compared to curative treatments.