Description: White grubs are the larval stage of scarab beetles and chafers. They feed on the roots of grasses and can be found in the top couple inches of soil. The body is creamy white with a reddish-brown head, and they have three pairs of legs on the thorax. They may reach nearly one inch long. Normally, they will be seen to curve their bodies into a distinctive C-shape. Most white grubs complete their development in one year. The adult stages of white grubs are scarab beetles. Common names for some of the species include June beetles, chafers, and dung beetles. Only a few species of white grubs’ damage turfgrass, and most feed on decaying plant material and animal manure, proving a necessary role in recycling nutrients of these materials. Native species of white grubs have long been common in Colorado, particularly in the TriRivers counties and in towns along the Arkansas and South Platte River valleys.

Injury: Injury to plants occurs as the white grubs feed on roots, which causes drought stress due to the root loss. In severe infestations turf roots are so severely pruned that areas of the lawn can be lifted or peeled back easily, as if it had been newly laid sod. Lawn areas can be killed by these injuries. The presence of white grubs in lawns is also attractive to raccoons and skunks, which will dig up lawns in search of grubs, often causing more damage than produced by the insects alone.