Management of rangelands for wildlife and livestock entails understanding growth of clonal shrubs such as Chickasaw plum (Prunus angustifolia Marsh.). We studied growth of this species in one county in north-central (Payne) and two counties in northwestern Oklahoma (Ellis, Harper) during 2006 and 2007. We estimated age of stems and roots by growth rings and area of stands with the use of a handheld GPS unit. Based on zero-intercept regression models, stands grew at similar rates (overlapping 95% confidence intervals [CIs]) among counties with a pooled estimate of 31.0 m² · yr⁻¹ (95% CI  =  26.5–35.6 m² · yr⁻¹; n  =  95). This rate showed considerable variability within and among study sites (r  =  0.52). Stem diameter increased (zero-intercept models) more rapidly in north-central Oklahoma (5.27 mm · yr⁻¹; 95% CI  =  5.01–5.53 mm · yr⁻¹; r  =  0.90; n  =  53) than in northwestern Oklahoma (3.68 mm · yr⁻¹; 95% CI  =  3.55–3.81 mm · yr⁻¹; r  =  0.91; n  =  102); data were pooled because of similar rates in Ellis and Harper counties. Stem height was a power function of stem age (y  =  0.97x^0.28; r  =  0.56), indicating rate of growth in height (m · yr⁻¹) declined with age according to dy/dx  =  0.27x^−0.72. Knowledge of the area expansion rate of Chickasaw plum clones aids in management planning to increase or decrease canopy coverage by this shrub.