Grubs are the precursor to various types of beetles. One of the most destructive grubs is Japanese beetle, which lives in turf. These critters chew through grass roots, creating dead patches in your lawn. The best time to control grubs is in early fall, when they’re young and feeding voraciously underground near the soil surface. Treat with parasitic nematodes, a microscopic worm that attacks grubs (Heterorhabditis bacteriophora is the best), or strap on a pair of lawn aerating sandals and spike the grubs to death. Concentrate your spiking steps on brown lawn areas and the green areas just outside the brown.