Only soils with low percentages of silt, clay, and gravel will do for the Texas Pocket Gopher, so many of its populations are isolated from one another. The species occurs in southern Texas and extreme northeastern Mexico, burrowing in deep, sandy soils and only infrequently emerging aboveground. It forages on plant root systems, and is capable of pulling some plants through the soil and into its burrow. While in the burrow, Texas Pocket Gophers keep any entrance to the surface plugged with soil; this closed-door policy not only helps to keep out unwanted guests, it also helps to maintain a suitable subterranean environment. Variation in size is one notable trait of the species, probably a result of population isolation.

Links:
Mammal Species of the World
Click here for The American Society of Mammalogists species account