Hay that has been baled with incorrect moisture content or that has been under the influence of moisture has potential to generate heat and create a fire hazard. Traditional means of monitoring baled hay temperature in storage, by inserting a pipe probe with thermometer, are time consuming. A ZigBee wireless sensor network could be used to remotely monitor internal hay bale temperatures. Tests were conducted to determine the maximum amount of hay through which a 2.4 GHz ZigBee module could transmit data and the resulting signal strength (RSSI). Based on analysis of the data, a ZigBee transmitter with 2 mW transmitting power can transmit data through 9 ft of baled hay and a ZigBee transmitter with 50 mW transmitting power can transmit data through 18 ft of baled hay. In general, RSSI decreased significantly with each additional 3 ft of baled hay.