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Soil carbon and ground cover were measured in 2005 on two sets of 24-year-old multiple grazing exclosures at "Croxdale ", a Queensland Department of Primary Industries & Fisheries (QDPI &F) research station near Charleville in south-west Queensland. Each trial consisted of three plots: (1) fully exclosed; (2) domestic stock exclosed and macropods able to graze; and (3) domestic stock and macropods able to graze. Total ground cover had changed little since measurements in 1985, although grass cover had significantly declined. The dominant component of total ground cover was mulga litter with small contributions from grasses and cryptogams. Soil carbon contents, to a depth of 30 cm, significantly differed between sites. More soil carbon was present in the fully exclosed sites than in areas grazed by macropods or macropods and domestic stock. The average soil carbon content in the fully exclosed plots was 8.2 t/ha greater than in plots exposed to grazing from macropods and domestic stock with much of the change being confined to one replication. The increase in soil carbon mainly occurred at depths between 10 and 30 cm. Simulation modelling suggests that the magnitude of measured changes may be due to a combination of reduced grazing and ongoing soil erosion in continuously grazed areas.