To protect your green lawn, you must know: what does a vole eat? Many homeowners wonder what do vole eat when they see dead patches of grass. These destructive voles are strict herbivores that feed on succulent grass, plant roots, and bulbs. Knowing exactly what do vole eat helps you clear their food source. A vole loves dense vegetation where it can hide and chew safely. If you don't limit what does a vole eat by trimming grass short, these voles rodents will ruin your yard's root system completely.