Grazing Management Affects Ecoturf Rhizoma Peanut Forage Performance and Canopy Structure.

Ecoturf rhizoma peanut (RP) is a decumbent legume that achieves relatively rapid ground cover when planted in pure stand and has shown ability to spread when strip planted into existing perennial grass swards. Very little grazing management research has been conducted with Ecoturf. The objective of this study was to determine the effect of various combinations of length of regrowth interval (RI) and grazing intensity on productivity, persistence, and nutritive value of Ecoturf RP. The six treatments were the factorial combinations of three levels of RI (1, 4, and 7 wk) and two levels of post-grazing stubble height (SH; 4 and 8 cm). The treatments were replicated three times in a completely randomized design. The experiment was conducted from June through October 2015. Response variables measured were herbage accumulation (HA), herbage harvested by grazing (HH), RP leaf percentage, RP proportion in pre-grazing herbage mass, and RP root-rhizome mass. Herbage accumulation (HA; 9.08 vs. 6.49 Mg ha^-1) and HH by grazing (7.03 vs. 3.33 Mg ha^-1) were greater for the 4- than the 8-cm SH, respectively, and for the 1- than the 7-wk RI (HA, 8.87 vs.7.00 Mg ha^-1; HH, 6.18 vs. 4.40 Mg ha^-1, respectively). In contrast, root-rhizome mass (5.50 vs. 4.63 Mg ha^-1) and percentage RP in pre-grazing herbage mass after 1 year of grazing (93 vs. 86%) were greater for the 8 than the 4-cm SH, respectively. Pre-grazing RP leaf percentage was high for all treatments ranging only from 56 to 61 across levels of RI and 57 to 61 for levels of SH. Ecoturf RP productivity was favored by frequent, close defoliation in the first year of grazing, but greater root-rhizome mass and percentage RP in herbage mass for the taller SH after 1 yr of grazing indicates the importance of assessing grazing responses for additional years.