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Cool-season perennial invasive grasses are a primary management concern on northern Great Plains rangelands in the USA. Management strategies to reduce these grasses often do not consider underlying mechanisms that can explain responses. One potential way around this constraint is evaluating axillary buds, which are meristematic tissue that provide the basis for future productivity. Our research projects evaluated responses of axillary buds of two perennial invasive grasses to different management strategies. In the first experiment, axillary bud numbers per m-2 were collected in the spring and fall of 2020 and 2021 from plots with ambient rainfall plus 2 different simulated drought intensities (30 and 60% of the ambient rainfall intercepted). Half of the plot under each rainfall intensity was burned, and the ot her half was left unburned. Both burning and moderate drought reduced the number of Kentucky bluegrass (Poa pratensis L.) axillary buds m-2 to 60% of the controls; however, the impact of burning changed with season and drought intensity. Regardless of burning or drought treatment, there were still over 400 active axillary buds m-2 suggesting a large pool of potential meristematic tissue was available for future growth. In the second experiment, smooth brome (Bromus inermis L.) tillers were clipped at vegetative, tiller elongation, and reproductive stages, and the number of axillary buds, tillers, and rhizomes (total outgrowth) was estimated in the fall over a 3-year period. Both total outgrowth and proportion of axillary buds that became outgrowth were greater when smooth brome was defoliated in the reproductive phase than when it was defoliated twice in the vegetative phase, suggesting the timing of defoliation may aid in smooth brome control. Both experiments suggest that evaluating the response of axillary buds and other demographic parameters provides mechanistic insights into the potential effectiveness of different management strategies for controlling invasive perennial grasses.