field capacity in Q3, problem set 2

Spencer, Consider that the concept of field capacity is qualitative (i.e. descriptive) thus the qualitative definition of the water content of soil after the "rapid" drainage (or water drained by gravity). Quantitatively we define this value as the soil water content at -10 to -33 KPa (depending on soil texture). Thus we measure field capacity of the "red" soil in question #3 (problem set #2) at -33 KPa.