Grazing strategies on range and pasture commonly are designed with grazing period length as a focus. Grazing period length can affect recovery period length and grazing pressure; thereby, possibly impacting aboveground plant production and heterogeneity of vegetation structure and composition. We are quantifying plant production, composition, and structural heterogeneity on upland pastures (sands ecological site) in the Nebraska Sandhills in response to different combinations of cattle grazing and recovery period lengths. Three grazing period lengths at each of two stocking rates are being tested on upland pastures grazed annually by cattle from mid-May to mid-October since 2010. Grazing period lengths are 3 days in a 50-pasture rotation, 37 days in a 4-pasture rotation, and 150 days in continuously-stocked pastures. Stocking rates are 1.9 AUM/ha (recommended) and 2.7 AUM/ha (1.5x). Plant functional group composition and aboveground production is estimated by clipping standing vegetation at ground level in 20 grazing exclosures (1 m2) per pasture in mid-August. Stubble heights are measured within 2 days following termination of grazing to estimate utilization and heterogeneity (variance among sampling points) by topographic position and pasture. Botanical composition and aboveground production response to grazing period length is trending towards interacting with stocking rate as aboveground production is relatively low at the 1.5x stocking rate on continuously-stocked pastures. Although 1.5x pastures have shorter post-grazing stubble height than the moderately-stocked pastures, stubble height among the grazing period length treatments generally has not differed. However, low-lying interdunal areas tend to be grazed to lower stubble heights in continuously-stocked pastures, thus favoring short grasses in this topographic position. Botanical composition response to grazing period length and stocking rate also will be reported.
Oral presentation and poster titles, abstracts, and authors from the Society for Range Management (SRM) Annual Meetings and Tradeshows, from 2013 forward.