Colonies of "C. formosanus" feeding on pecan, "Carya illinoensis" and red gum, "Liquidambar styraciflua" produced significantly more progeny than colonies feeding on other wood species tested. Progeny of colonies feeding on pecan and American ash "Fraxinus americana" had significantly greater survival than progeny of colonies feeding on other wood species. Colonies feeding on nutritionally supplemented, cellulose-based matrix showed similar fitness characteristics as colonies feeding on the best wood treatments. These results indicate that differences observed in colony fitness can be partially explained by nutritional value of the food treatment, raising the possibility that wood from different tree species has different nutritional values to the Formosan subterranean termites. This suggests that feeding preference of "C. formosanus" is at least partially influenced by the nutritional value of the food source.