Location: Pasture Systems & Watershed Management Research
Title: Out with the old, in with the new: does mob grazing have a place in northeastern grazing systemsAuthor
Billman, Eric | |
WILLIAMSON, JESSICA - Pennsylvania State University | |
Soder, Kathy | |
Andreen, Danielle |
Submitted to: Popular Publication
Publication Type: Popular Publication Publication Acceptance Date: 10/1/2019 Publication Date: 10/20/2019 Citation: Billman, E.D., Williamson, J., Soder, K.J., Andreen, D.M. 2019. Out with the old, in with the new: does mob grazing have a place in northeastern grazing systems. Popular Publication. p. 1. Interpretive Summary: No Interpretive Summary is required for this Popular Publication. JLB. Technical Abstract: Two competing grazing methods, rotational and mob grazing, have become prevalent in most grazing systems throughout the last several decades. Rotational grazing is centered on moderate stocking densities for a few days, while mob grazing involves intensive stocking for very short time periods. A 4-year comparative study was conducted at the Pennsylvania State University Hawbecker Research Farm in Bellefonte, PA to determine how prolonged mob and rotational grazing affect forage yield, quality, and species composition in pastures. Eight paddocks were arranged in a randomized complete block design with four replications, with odd numbered paddocks being mob grazed and even numbered paddocks being rotationally grazed. All grazing was conducted using yearling beef steers. Rotationally grazed paddocks were grazed between May and October each year, whenever sward height reached 25 cm, and mob grazed paddocks were grazed in June and September each year. Annual cumulative yield was greater for rotational grazing than mob grazing (P < 0.10 – 0.01) in all but the second year, with both systems experiencing declines in yield with each successive year. Mob grazed pastures showed greater yields at individual harvests in all but the final grazing period of the study (P < 0.01). Forage grasses persisted more under rotational grazing, while alfalfa came to dominate the mob grazed systems. (P < 0.05 – 0.001). Finally forage acid detergent fiber (ADF) and lignin were consistently lower under rotational grazing (P < 0.10 – 0.001). Therefore, rotational grazing may be a more viable method for maintaining long-term yields and forage quality in a given pasture, compared to mob grazing, but mob grazing may allow for greater yields close to establishment. |