Sulfosulfuron (1-(4,6-dimethoxypyrimidin-2yl)-3-[(2-ethanesulfonyl- imidazo[1,2-a]pyridine-3-yl)sulfonyl]urea) is an herbicide commonly applied to warm-season turfgrasses to control various sedges and broadleaf weeds.  In a field trial, sulfosulfuron was applied to two cultivars of St. Augustinegrass (Stenotaphrum secundatum (Walt.) Kuntze), cv. ‘Raleigh' and ‘Palmetto', at 0.66, 1.25, 2.50, and 5.0 oz acre-1 and evaluated for herbicide tolerance.  The cultivar ‘Raleigh' showed no signs of injury, whereas, ‘Palmetto' injury increased with higher application rates.  The greatest injury was in the form of reduced canopy height.  Higher application rates correlated to greater shoot growth suppression.  A second study was initiated in the greenhouse to evaluate the effect of sulfosulfuron on ‘Palmetto' root growth.  Using the WinRhizo System, changes in root architecture were evaluated at 2, 4, and 8 weeks after treatment.  ‘Palmetto' did not exhibit any change in total root length, surface area, or average diameter regardless of application rate.  Therefore, based on these results, sulfosulfuron can be safely applied to both cultivars of St. Augustinegrass with no deleterious effects on ‘Palmetto' root growth.