Abbreviations: BS T, evapotranspiration calculated by theoretical water balance; BS FDR , actual evapotranspiration calculated by water balance using a sensor with frequency domain refl ectometry * Significant at the 0.05 probability level. ** Significant at the 0.01 probability level. † Within a column, means followed by the same letter are not significantly different according to LSD (0.05). ‡ ns, nonsignificant at the 0.05 probability level.