Pocket gophers are often the most damaging vertebrate pests in alfalfa. The amount and form of damage they cause can be quite varied but includes a loss in vigor and/or mortality of plants, damage to subsurface drip lines and loss of irrigation water down burrow systems.

Although many vertebrate pests cause problems in alfalfa, the most frequent offenders are often pocket gophers (geomyidae) and meadow voles (also known as meadow mice; Microtus spp.). Pocket gophers are short, stout burrowing rodents, usually 6 to 8 inches in length.

Although many vertebrate pests cause problems in alfalfa, the most frequent offender is the pocket gopher (hereafter gopher; Thomomys spp.).