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Interseeding alfalfa (Medicago sativa L.) into bermudagrass [Cynodon dactylon (L.) Pers.] can be an effective way to improve forage quality and reduce the need for additional supplementation when fed to livestock. The objective of this research was to compare the nutritive value and forage mass of bermudagrass with and without interseeded alfalfa when harvested as baleage. On 19 Feb. 2016, 0.2‐ha plots were assigned in a randomized complete block design to either ‘Tifton 85’ (T85) or T85 interseeded with ‘Bulldog 805’ alfalfa (T85+Alf) in an established field of Tifton 85 bermudagrass at the University of Georgia Tifton Campus, Tifton, GA. The T85 received 84 kg N ha−1 four times throughout the growing season. Plots were harvested at early bloom stage every 28–35 d throughout the growing season, baled at 40–60% moisture, and individually wrapped. At each harvest, plots were evaluated for botanical composition and forage mass, and bales were sampled prior to wrapping for nutritive value analysis. The T85+Alf plots produced additional harvests each season, leading to greater herbage accumulation than T85 plots (P < .01). The T85+Alf treatment had greater crude protein and total digestible nutrients than T85 in each of the 3 yr, suggesting this mixture will need no or less supplementation to meet the nutritional requirements of a lactating beef cow. Therefore, interseeding alfalfa into a bermudagrass system improves forage mass and nutritive value.

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The efficacy of enhanced-efficiency (EE) nitrogen (N) fertilizer formulations in reducing N loss and improving the efficiency of urea-based fertilizer products in forage production is unclear. This study compared ammonium nitrate (AN), urea, four EE urea N formulations [A/-(n-butyl) thiophosphoric triamide (NBPT)-treated urea, NBPT and dicyanamide-treated urea, a polymer-coated urea (PGU), and a maleic-itaconic copolymer-treated urea (MICPU)], urea-ammonium nitrate (UAN), and two EE UAN formulations (NBPT-treated UAN, NBPT and dicyanamide-treated UAN) in forage bermudagrass [Cynodon dactylon (L.) Pers.] production. The experimental design was a randomized complete block design with four replications in each of two sites and 2 yr (2008)(2009). Treatment applications were made at the rate of 168 kg N ha ' spring dormancy-break (ca. 30 April) and after the second harvest (ca. 25 July; total of 336 kg N ha ^ season). Response variables included trapped ammonia (NH3) and forage yield, production efficiency, N concentration, N uptake, recovery of applied N, and nitrate concentration. Urea treated with NBPT reduced NH3 volatilization and, in some situations, increased agronomic response relative to urea. Addition of NBPT produced results similar to AN and UAN, and it was never detrimental relative to untreated urea. The MIGPU treatment was ineffectual relative to urea alone. The PGU reduced NH3 volatilization and improved N concentration in the forage but did not improve other agronomic characteristics. Use of UAN solutions produced results that were generally intermediate in response between urea and ammonium nitrate and were not improved by NBPT addition. Adding NBPT can reduce NH3 volatilization and increase the efficiency of urea, but further research is necessary to understand the limits of this additive.

Regenerative agriculture is a newly codified approach to agriculture that emphasizes reducing reliance on exogeneous inputs, as well as restoring and enhancing ecosystem services such as soil carbon (C) sequestration. These regenerative agriculture principles suggest that modern livestock systems can be redesigned to better capitalize on animals' ecological niche as biological up cyclers and may be necessary to fully regenerate some landscapes. One example is a multispecies pasture rotation (MSPR) system, which symbiotically stacks multiple animal production enterprises (i.e., chickens, cattle, sheep, and pigs) on one landscape. We conducted a whole-farm life cycle assessment (LCA) of an MSPR in the southeastern United States that was originally converted from degraded cropland. We compared the production outputs, greenhouse gas (GHG) emissions, land footprints, and soil health outcomes to a conventional, commodity (COM) production system of each respective species. Our 20-year MSPR chronosequence of soil C and other soil health indicators shows dramatic improvement since establishment, sequestering an average of 2.29 Mg C ha−1 yr−1. Incorporation of soil C sequestration into the LCA reduced net GHG emissions of the MSPR by 80%, resulting in a footprint 66% lower than COM. However, when comparing required land between the two systems for food production, MSPR required 2.5 times more land when compared to COM. Thus, while our model indicates that MSPR can simultaneously produce protein while regenerating land, a considerably greater land area is needed when compared to COM. Our results present an important yet paradoxical conclusion on land and food production balance. Should society prioritize an input-intensive, COM system that produces more food from a smaller yet degrading land base? Or, alternatively, should systems such as MSPR that produce less food on a larger, but more ecologically functional landscape be more highly prioritized? These complexities must be considered in the global debate of agricultural practice and land. Our results indicate MSPRs are a useful model for alternative livestock production systems with improved environmental outcomes, but in this study may present considerable land-use tradeoffs.