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Kentucky bluegrass (Poa pratensis L.) is a perennial, cool-season invasive grass throughout the northern Great Plains. It can provide adequate early spring grazing, but forage quality declines quickly with maturity. Timed grazing can impact plant species and can shift plant communities to a more desired state. Higher animal densities may be necessary to affect target species. However, animal performance and overall economic benefit to the livestock producer need to be considered. A five year timed grazing study at the Central Grassland Research Extension Center, North Dakota, compared early-intensive grazing with season-long grazing on Kentucky bluegrass foliar cover. Beef heifers, moderately stocked on both treatments, were removed from the early-intensive treatment when thirty percent of native vegetation had received some grazing. Stocking rate was similar across both treatments, but stocking density was over three times higher on the early-intensive treatment. Forage production was not significantly different (P<0.05) between early intensive and season-long grazing treatments in any of the five years. However, Kentucky bluegrass foliar cover was less on the early intensive treatment (23.5�6.42 vs. 53.46�1.75 P=0.001). Heifers gained more (P<= 0.05) in season-long pastures, with a corresponding weight loss on the early intensive treatment (0.37 vs -1.04 lbs/day, respectively). However, early spring forage production in 2015 was less than in prior years of this study due to a dry winter. While early intensive grazing appears to be an effective long-term management strategy to reduce Kentucky bluegrass, animal performance should also be considered, especially in the case of pre-breeding females with higher nutritional needs. Grazing animal age and stage should be matched accordingly on a yearly basis.