Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 3/14/2020
Publication Date: 1/9/2020
Citation: Billman, E.D., Williamson, J., Soder, K.J. 2020. mob or rotational grazing for northeastern pastures: an Offer you can't refuse[Abstract]. Meeting Abstract. p. 1.
Interpretive Summary: No Interpretive Summary is required for this Abstract. JLB.
Technical Abstract: In the northeastern United States, rotational grazing is the standard system implemented by producers. However, there is increased interest in incorporating mob grazing, a grazing system popular in the western United States, due to less intensive management needs, and potential increases in forage availability. However, little knowledge exists on the efficacy of mob grazing in northeastern grazing systems. We conducted a 4-year grazing trial (2015-2018) in collaboration with Penn State University to address this question. Eight 0.25 acre paddocks were arranged in a randomized complete block, with four replications, with four paddocks assigned to be rotational grazed (ROT), and four assigned to be mob grazed (MOB). All paddocks were grazed by angus-cross yearling cattle, with ROT using 15-head (48,000 lbs/acre), while MOB used 40-head, concentrated within eight smaller sections (1 million lbs/acre). Two MOB events occurred each year, compared with 4 – 6 ROT events. Each paddock was seeded with a 5-species mix of orchardgrass, alfalfa, tall fescue, white clover, and narrowleaf plantain. By the conclusion of the trial, annual, cumulative forage accumulation was significantly greater in the ROT paddocks (P < 0.01), while MOB paddocks had greater forage accumulation at individual grazing events throughout the years (P < 0.05). Additionally, species composition of the paddocks differed under each treatment, with grasses persisting better under ROT, and alfalfa being the dominate species under MOB (P < 0.05). Finally, forage fiber concentrations (ADF and lignin) were significantly lower under ROT (P < 0.05). These findings suggest that ROT is a more sustainable grazing system for the Northeast, but that MOB may be useful in situations where large acreage and herd size can be used to take advantage of greater forage accumulation.