Gnathamitermes tubiformans (Buckley), a common termite species in the northern Chihuahuan Desert of North America, builds mud galleries around standing dead vegetation and other food materials after periods of rain. The termites graze only the surface of standing dead branches, tissues highest in nitrogen content. We hypothesized that termites invest more energy in gallery construction than they obtain from the wood they consume. We estimated energy costs of gallery construction from analysis of gallery material and construction behavior of the termites. In addition to obtaining a food source relatively high in nitrogen, the estimated energy invested in gallery construction. Therefore, the termites obtain much more energy from wood than they invest in gallery construction.