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Understanding how different grazers, such as cattle and prairie dogs, impact tiller recruitment, can help develop state and transition models needed for ecological site descriptions. Study areas were selected on two different ecological sites, thin claypan and loamy, both with and without prairie dogs on a ranch near Mahto, SD. Livestock exclosures were fenced on each study area two years prior to the start of the study and paired with nearby non-exclosed areas. Therefore, on each ecological site, the grazing treatments were 1) No cattle, no prairie dogs (NCND), 2) cattle, no prairie dogs (CND), 3) no cattle, prairie dogs (NCD) and 4) cattle, prairie dogs (CD).� In spring 2014, all the western wheatgrass tillers [Pascopyrum smithii (Rydb.) �. L�ve] within 4 randomly located subplots (15 x 15 cm) in each main plot were counted and marked with a colored wire.� The subplots were revisited in the fall of 2014 and the spring and fall of 2015 and 2016 to evaluate tiller mortality and recruitment. Tiller tiller-1 recruitment greater than 1 indicates a growing population. �Years 2014 (1.02) and 2016 (0.85) had greater (P=0.0005) tiller tiller-1 recruitment than 2015 (0.41) and tiller recruitment was greater (P=0.0073) on the thin claypan (0.84) than the loamy site (0.68). However, in the Spring 2015, the loamy site (0.53) had greater recruitment than did the thin claypan site (0.31).� Tiller recruitment was highly variable with CND and NCND having tiller tiller-1 recruitment greater than 1 in 2014 but CD and NCD having tiller tiller-1 recruitment close to 1 in 2016.� Year rather than grazing intensity may drive tiller recruitment. Increased recruitment on the thin claypan site may be the result of longer prairie dog occupation on these sites.� Analysis of survivorship data should provide a clearer picture of the tiller dynamics on these sites.