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Recent trends in livestock grazing have led to an increasing use of higher stocking densities, shorter grazing periods, and increased focus on recovery length, culminating in the practice of “mob grazing”  with stocking densities of 225,000 kg per ha or more and multiple movements of livestock from pasture to pasture per day. Proponents of the practice claim increased plant production, soil development, and nutrient cycling rates because of the spatial uniformity of intensive trampling resulting from ultrahigh stocking densities. The purpose of this study was to determine grazing method effect on annual root production. The study was conducted in 2012 and 2013 on a subirrigated meadow at the University of Nebraska-Lincoln Barta Brothers Ranch in the Nebraska Sandhills. Grazing methods included two replications of mob grazing (224,170 kg/ha), 4-pasture rotation grazing (6,725 kg/ha in 2012 and 4,483 kg/ha in 2013), continuous grazing, and an ungrazed control. Cattle grazed treatment pastures for 60 days from early June to early August. Prior to the growing season in May, 12 soil cores (5 cm diameter by 15 cm deep) were removed per treatment replication. The cores were split into upper (0-7.5 cm) and lower (7.5-15 cm) portions and dried.  The dried portions were sieved to remove existing root material.  Mesh containers were then placed into the core holes and filled with the sieved portions of soil.  At the end of the growing season in November, cores were excavated and roots trimmed to the edge of the core container.  Samples were then sieved, removing the root mass.   Roots were separated from the soil in a hexametaphospate solution (1 gram/ 200 mL H2O) using a shaker table and hand washing.  Once processed, roots were dried and weighed.  Treatment comparisons of root weights will be presented.