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Overgrazing, or failing to adjust stocking rates to match annual forage production, traps land in a cycle of degradation. From 201 5 to 202 4, two adjacent catchments in the Brigalow Belt bioregion of central Queensland were grazed by beef cattle. One catchment was stocked at or below the safe long-term carrying capacity. The other was stocked at the recommended stocking rate for newly established buffel grass pasture on recently cleared and developed brigalow land, which made no allowance for pasture productivity decline over time resulting in overgrazing. The minimum ground cover in the catchment stocked at the safe long-term carrying capacity was 82% and end of dry season pasture biomass was always greater than 780 kg/ha. The proportion of buffel grass in this pasture averaged 93% throughout the study. In comparison, the overgrazed catchment had a minimum ground cover of 72% and end of dry season pasture biomass was as low as 46 kg/ha. At the commencement of this study, 88% of the overgrazed pasture was comprised of purple pigeon, buffel, and Indian couch grasses (54%, 27% and 7%, respectively). However, after 10 years, purple pigeon grass was almost absent and the proportion of buffel and Indian couch grasses in the pasture was 1% and 92%, respectively. Overgrazing resulted in a decline in biomass, changed species composition, and the loss of the perennial, palatable and productive purple pigeon grass. Although ground cover initially declined as the tussock grasses disappeared, it recovered with Indian couch invasion. Previous research has shown that overgrazing also substantially altered catchment hydrology, with runoff and erosion more than tripling in the first five years. Conceptually, as runoff increases, the amount of rainfall stored in the soil for plant growth decreases, leading to lower ground cover and pasture biomass. Unless an intervention such as a reduction in stocking rate is undertaken, pasture utilisation will continue to exceed pasture production, and land degradation will continue.