Small unmanned aerial systems (UAS) can be very useful for acquiring high resolution thermal imagery for many ecological applications. With these systems, routine ground sampling is important in order to calibrate the imagery and to understand unique environmental disturbances. Simple, accurate methods to sample surface temperature is needed. This paper introduces two methods for sampling ground surface temperatures. One method uses a ground-based thermal camera to capture a high-resolution sample of a small area. The other method uses temperature controlled pools, which can be seen from the aerial thermal image. These samples are used to calibrate a thermal mosaic captured by the UAS AggieAir. Accuracy and simplicity are evaluated for each method.