The amount of water that topsoils of the Patumahoe clay loam can retain at tensions between 0.2 and 15.0 bars (available-water capacity) has been determined for four sites under pasture and eleven sites in market gardens. The mean available-water capacity of the 2–12 cm depth was 18% of soil volume under pasture and 11% in gardens; for the 12–22 cm depth the mean available-water capacity was 10% under pasture and 12% in gardens. The difference between pasture and gardens was highly significant for the upper topsoil but not significant for the lower topsoil; the available-water capacity varied significantly with depth under pasture but not in gardens. The large available-water capacities near the surface under pasture derived from exceptionally high values of field capacity which may have been related to high contents of organic carbon in the soil. Any advantage of the pasture over the cultivated sites in the water-supplying power of the topsoil as a whole was of doubtful significance.
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