Income derived from the operation of a motel or a smokeshop (Critzer v. United States, 596 F2d 708 (ct. Cl.), cert denied and Dillon v. United States 792 F2d 849 (9th Cir. 1986), cert. denied) on allotted land has been held to be derived from labor and the use of capital improvements rather than directly from the land itself, and has been determined to be taxable.