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The standard practice for calculating carbon stocks in soil is tonnes per hectare (t/ha) to a depth of 0.3 m. Such calculations are influenced by the greater proportion of carbon in the 0.0 to 0.1 m depth, but sampling to 0.3 m provides additional information on the impact of management practices. Regardless, only sampling to a depth of 0.3 m neglects a substantial portion of carbon in profile soil. Intrigued by this conundrum, profile samples from the Brigalow Catchment Study were analysed for Walkley and Black soil organic carbon (SOC) for three land uses: remanent brigalow woodland, cropping and grazing. Samples were collected from Vertosol soils to a maximum depth of 4.4 m in 2018, 36 years after clearing of the two agricultural land uses. In agreement with earlier studies, there was less carbon under cropping than grazing or brigalow woodland. On average there was 42 t/ha of carbon in the top 0.3 m of soil under grazing and woodland which accounted for 56% of the SOC stock to 4.4 m, compared with only 28 t/ha under cropping which accounted for 48% of the SOC stock to 4.4 m. Carbon stocks were steady below 1.8 m for all three land uses, and carbon in the 0.3 to 1.8 m depths accounted for 30% of the total SOC stock to 4.4 m. Root biomass is the main input of organic carbon in to soil, and l and management practices that promote perennial pastures and native vegetation with deeper root systems increase the opportunity of profile soil to sequester carbon.