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Woody encroachment is a global phenomenon on numerous continents (e.g. Africa, Australia, N. America). In North American grasslands, managing tree/shrub proliferation has been challenging, as its causes are varied and actively debated. Social factors (e.g. culturally-ingrained differences in the use of prescribed fire) have contributed to woodland expansion but are seldom factored in to ecological models. Great Plains grasslands are largely comprised of private lands. This, coupled with a lack of consistent fire policy within and across state boundaries, has led to high spatial variability of fire. We used fire occurrence data (1984 � 2012) from N. Dakota to Texas to identify areas with relatively low (<0.65) and high (>0.65) fire probabilities. We aimed to predict how potential woody cover and stature (key surrogates for biomass and C-mass) vary as a function of fire x climate interactions in these contrasting areas. Results suggest that woody plant height is largely dictated by mean annual precipitation (MAP). However, under low and high fire regimes, their height was restrained to ~3m and ~5 m in areas receiving ?800mm and ?1050mm MAP, respectively. In contrast to height, % cover was mainly predicted by mean annual temperature (MAT). Here, warmer areas (e.g. Texas) had greater woody cover than cooler areas (e.g. Kansas) with no consistent relationship with fire and MAP. Overall, MAP, MAT and social constructs (e.g. landowner, burn associations) were the main predictors of fire dynamics. Understanding the interactions between these variables will allow us to better predict areas of future woodland expansion.