Field studies were conducted in 2009-2010 to evaluate a combination of dithiopyr and sulfentrazone. Applied as a liquid or granular formulations for preemergence (PRE) and postemergence crabgrass control. The ratio of dithiopyr and sulfentrazone was approximately 5:4, application rates were 0.5, 0.7, and 1.0 kg ai/ha. Application timings were PRE, 1-4 leaf, 1-2 tillers, and 3-5 tillers (2010 only).  All granular treatments were applied by hand to dry foliage with a shaker can to plots that were 0.9 by 3 m.  All liquid treatments were applied to 0.9 by 3 m plots with a single-nozzle CO₂ backpack sprayer system utilizing a 9504EVS nozzle tip which delivered 374 L/ha of spray solution at 221 kPa. Experimental design was a randomized complete block with 4 replications. Treatments were visually evaluated for crabgrass control in late August. In 2009 crabgrass control with PRE applications ranged from 90-99% while dithiopyr (2EW) alone at 0.6 kg/ha was 96%. Control of 1-4 leaf crabgrass ranged from 70-98% with the 1.0 kg/ha rate providing the highest level of control. Control of 1-2 tiller crabgrass ranged from 34-87%. Control significantly increased with increasing application rate. Crabgrass control was significantly greater with the granular formulation at 0.5 kg/ha. In 2010 granular and liquid formulations were evaluated in separate studies. 0.6 kg/ha of dithiopyr was included at each application timing. In the liquid formulation study crabgrass control with PRE treatments ranged from 76-86%. All treatments applied to 1-2 or 3-5 tiller crabgrass resulted in significantly less control relative to PRE treatments. In the granular formulation study PRE treatments provided 88-98% control. Control of 1-4 leaf crabgrass ranged from 85-98% and was equivalent to PRE treatments. Control of 1-2 tiller crabgrass ranged from 61-95% with application rates of 0.7 and 1.0 kg/ha providing equivalent control to  PRE treatments. Treatments applied to 3-5 tiller crabgrass provided 65-81% control and was significantly lower relative to PRE treatments. The results of these studies suggest that granular formulations of dithiopyr and sulfentrazone provide a significant level of postemergence crabgrass control up to 1-2 tillers.