The moisture content (MC) of felled trees has a direct impact on transportation costs and efficiency. Transpirational (or field) drying of fallen trees, to reduce MC and subsequently improve the economics of transport can be employed; however, an understanding of seasonal drying rates is required. Typically load cells have been used to track moisture changes in bundles of logs but where access is limited this approach is impractical. Time-domain reflectometry (TDR) provides an alternative approach and was used to monitor seasonal changes in transpirational drying rates for felled loblolly and slash pine at a Lower Coastal Plain site in Florida and loblolly pine at a Piedmont site in Georgia on a weekly basis for approximately one year. Different transpirational drying rates and minimum MC’s were observed by season. Drying rates observed during summer, fall and spring, at both test locations, indicate that after three weeks an equilibrium (or minimum) MC is achieved. Winter drying is slower, and up to 5 weeks in the field (or even longer) may be required. Post equilibrium felled log moisture content continued to vary during most seasons with rainfall events the most probable cause. TDR provides a viable approach for monitoring transpirational drying and subsequent MC changes in felled trees.

砍伐树木的水分（MC）直接影响运输成本和效率。可以采用蒸腾（或田间）干燥倒下的树木，以减少MC并随后改善运输的经济性；但是，需要了解季节性干燥率。通常，称重传感器已用于跟踪原木捆中的水分变化，但是在限制进入的地方，这种方法不切实际。时域反射法（TDR）提供了另一种方法，用于监测佛罗里达州下沿海平原站点的砍伐的火炬松和深松的蒸腾速率和乔治亚州的皮埃蒙特站点的火炬松的蒸腾速率的季节性变化，大约一年。各个季节观察到不同的蒸腾干燥速率和最小MC。在夏季，秋季和春季在两个测试位置观察到的干燥速率表明，三周后MC达到平衡（或最小）。冬季干燥较慢，在田间可能需要长达5周的时间（甚至更长）。平衡后下降的原木水分含量在大多数季节持续变化，降雨事件是最可能的原因。TDR提供了一种可行的方法来监测蒸腾干燥和砍伐后树木中MC的变化。