Fine roots play a critical role in nutrient acquisition and water uptake. Yet it is unclear how fine roots in arid environments respond to increased nitrogen deposition and summer rainfall, two important global change factors in arid lands in the southwestern United States. We measured fine root length density (RLD) for two years in experimentally manipulated plots in a Mojave Desert ecosystem using minirhizotron techniques. The study was conducted at the Mojave Global Change Facility located at the Nevada Test Site 60 miles northwest of Las Vegas. The treatments included: 1) three 25 mm water additions during the summer, 2) one 40 kg ha^-1 yr^-1 nitrogen addition in the fall, 3) a combined water and nitrogen addition and, 4) untreated controls. Root images were collected approximately every 90 days underneath shrubs and intershrub areas down to a depth of 90 cm. The RLD showed clear seasonal patterns with the fastest increase in RLD occurring between February and April while the increases were lowest between June and December. Preliminary data analysis indicates that during the winter the increase in RLD was higher underneath shrubs than in intershrub areas but during the summer months no difference was detected between shrubs and intershrub areas. Water additions slightly increased root mortality under shrubs and intershrub areas but not enough to significantly affect overall RLD. Nitrogen addition had no effect on fine root production, mortality and RLD. Our results indicate that increased summer rains and nitrogen deposition will have a very limited effect on fine root activity. In contrast, fall/winter rainfall has a strong impact on fine root dynamics since fine root production was much higher during a wet winter than during a 'normal' winter both under shrubs and in intershrub areas. Also, during wet winters root-distribution tended to shift to deeper soil layers.