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An improved understanding of the factors that influence stream temperature in rangeland environments can better enable the protection of stream ecosystems. The objectives of this study were to determine stream temperature-vegetation shading relationships and characterize other factors, such as subsurface flow and ambient conditions, on stream temperature in a semiarid watershed. �Data collection occurred at four observation sites in the Fifteenmile Creek subwatershed in north central Oregon. Three of the observation sites were located along Fifteenmile Creek and one was located along Ramsey Creek, a tributary of Fifteenmile Creek. �Air and stream temperature measurements were recorded at all sites. Intensive data collection occurred along a 1-km riparian corridor of Fifteenmile Creek. Riparian vegetation composition and cover was analyzed using field surveys along this corridor. Shallow wells were used to characterize subsurface flow temperature from an intermittent tributary stream along this reach. �Stream temperature data was collected using standalone sensors beginning in the spring of 2014 and using Distributed Temperature Sensing (DTS) in the summer of 2015. Comparisons of stream temperature data from standalone sensors and DTS found both to be in close agreement. No significant differences in stream temperature were found between sensors located in shaded and non-shaded regions of the stream (P?0.05). Fluctuations in stream temperature followed those observed in ambient temperature. Shallow groundwater temperatures in the intermittent stream were cooler than main stem stream temperatures in the summer and warmer during winter months, indicating the tributary may have a moderating effect on stream temperature. The results of this research indicate that factors in addition to riparian shading, such as groundwater inputs and stream velocity, may significantly influence stream temperature in this study area. Future research includes the use of Unmanned Aerial Vehicles (UAVs) to collect information about vegetation and ambient conditions.