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In conifer-encroached areas, one mechanism thought to contribute to the loss of understory species is the interception of precipitation by the increasing tree canopy. Effective precipitation may be reduced in rangelands encroached by western juniper (Juniperus osteosperma) and pinyon pine (Pinus monophylla) since trees have a large, dense canopy that can capture precipitation and allow it to evaporate before it can reach the soil surface. Recent research has quantified rainfall and snow interception by pinyon and juniper species, but little research has been conducted on the other vegetation in these systems, including big sagebrush (Artemisia tridentata). Understanding interception loss from understory vegetation is necessary to determine if pinyon and juniper in fact influence effective precipitation. To measure rain interception of mountain big sagebrush in the field, we are simulating storms over five 1.5 by 3 meter plots located in the Desatoya Mountains in central Nevada. Plants in each plot will be manipulated to test known canopy cover levels of 50%, 35%, and 20%. Each cover level will receive a minimum of 4 different storm intensities. Preliminary data from 11 rain simulations indicate that stands of sagebrush with approximately 50% canopy cover intercepts between 9.0 and 39.4% of rain storms ranging from 1.6 mm to 17.1 mm intensities. For comparison, plot-level interception for pinyon and juniper with 38% canopy cover measured in the same canyon intercepted 29.2% and 30.8% for 5 mm and 20 mm storm intensities, respectively. Scaling interception loss to a landscape level will aid in understanding the effect of various land management practices on soil moisture, groundwater recharge, and surface water availability.