We characterized nest-sites of the southern flying squirrel (Glaucomys volans) in a pine-oak forest located in Hidalgo, Mexico, and compared habitat variables between plots with nests and random plots without observed nests. We also compared areas of mature forest with forested areas under management. We detected 31 leaf nests or dreys along two streams in mature forest and none in forest under management; 93.6% of dreys were constructed on branches of live oaks (Quercus laurina). Plots with nests had significantly more snags, more rocks, and steeper slopes than plots without observed nests. No difference was found in the number of trees. In plots with nests, oaks were the dominant trees, mainly Q. laurina, while pines (Pinus) were more abundant in plots without observed nests. Given the propensity for these squirrels to build leaf-nests, availability of snags and cavities in this region may not be a limiting factor for G. volans as has been suggested previously.