This is the larva of the Green June beetle (Cotinis nitida [L]) commonly called white grub.
The larvae have the habit of crawling on their backs. They damage grass by feeding on the roots. The larvae pass the winter deep in the soil. In the spring, they tunnel near the surface where feeding takes place. They pupate in June and the adults emerge in July and August. There is one generation each year.
Plants growing in soils high in organic matter are usually damaged more than those in other type soils.
