Grubs feed on all types of grass roots, and then they damage lawns. Moles digging in the turf or flocks of birds feeding on your lawn are possible signs of white grubs or grub worms. Many Master Gardeners swear by a product called Milky Spore to take care of grub worms and Japanese beetles, too. If you're digging in the dirt and come across one of these white, curled up worms, crush it immediately.