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Both equilibrium and non-equilibrium dynamics are recognized as important drivers of rangeland ecosystems. Conceptual state-and-transition models (STMs) attempt to incorporate both equilibrium and non-equilibrium dynamics by including phase shifts as well as state transitions. Phase shifts are reversible with changes in climate or “facilitating” management practices (e.g., reduced grazing), while state transitions are reversible only with “accelerating” practices (e.g., erosion control, reseeding, brush removal). Grazing management is a pervasive driver of state transitions in existing STMs. In a northern mixed-grass prairie ecosystem, we documented plant community responses to (1) grazing intensity treatments (none, light, moderate and heavy) that were imposed continuously for 32 years, and (2) new experimental treatments in which pastures grazed heavily for 25 years were subjected to either light or no grazing for 7 years. Long-term grazing treatments were associated with distinct, but not stable, plant communities. From year 22 to year 32, more intense grazing was associated with increases in the cover of the dominant warm-season grass and decreases in the cover of dominant cool-season grasses and forbs. After 25 years of heavy grazing, pastures converted to light or no grazing for 7 years showed signs of incipient recovery, particularly for dominant cool-season grasses. However, recovery rates were quite slow. After 7 years of light or no grazing, the cover of dominant cool-season grasses in formerly heavily grazed pastures was similar to that in long-term moderately grazed pastures, but was still only 61% of cover in long-term lightly grazed pastures. In this grazing-adapted rangeland, our long-term grazing treatments did not drive the system into resistant alternative states, but instead caused continuous, directional, and reversible phase shifts with critical management consequences. In some systems, documenting gradients and rates of change within a single state may be more important for managers than identifying thresholds between alternative stable states.