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Grasslands in the northern Great Plains of North America sustain abundant plants, wildlife, and livestock but are threatened by invasive plant species. Predicted shifts toward more variable weather will challenge sustainable management of these grasslands. Effective and feasible management options need to be developed in collaboration with, and for, land managers. As part of the Long-Term Agroecosystem Research (LTAR) network, a nationwide network with 19 research sites focused on developing strategies to address current agricultural needs, we initiated an experiment in 2019 to answer whether applying fire and /or grazing can reduce the dominance of invasive Kentucky bluegrass (Poa pratensis) in North America's northern Great Plains ecosystems. We contrast a prevailing practice (season-long grazing at a moderate stocking rate) with four alternative practices at a half-hectare plot scale: (1) mob grazing (high intensity, short duration) by cattle, (2) multi-species grazing (mob grazing by cattle, with goats foraging at key times of the year), (3) prescribed fire, and (4) prescribed fire followed by cattle grazing. A stakeholder group was engaged in making decisions to determine alternative practices and how to apply them. Every five years, the treatment with the best overall outcomes is applied at a field scale (15 ha). We found that prescribed fire and mob grazing reduced the cover of Kentucky bluegrass and increased the cover of some native plant species. When combined, prescribed fire and grazing had the most reductions in Kentucky bluegrass and increases in native plant species. However, there are trade-offs associated with each treatment related to plant production and nutritive values, livestock weight gain, and soil compaction and infiltration. We discuss results in the context of optimizing land management based on land manager goals and current and future economic and ecosystem benefits.