Forage crops have the potential to serve multiple functions, providing an ecological framework to sustainably intensify food production, i.e., ecological intensification. We review three categories of forages (annual forages, perennial forages, and dual-use perennial crops/forages) we believe hold the greatest promise for ecologically intensifying food production. Annual cover crops can provide additional forage resources while mitigating nutrient losses from agricultural fields when they are intercropped with, interseeded into, or following an annual crop, for instance. The integration of perennial forages either temporally, such as annual crop rotations that include a perennial forage phase, or spatially, such as the intercropping of perennial forages with an annual cash crop, provide weed suppression, soil quality, and yield and crop quality benefits. Dual-use crops/forages can provide forage and a grain crop in a single year while providing multiple ecological and economic benefits. However, tradeoffs in balancing multiple functions and limitations in reducing the risks associated with these practices exist. Advancing our understanding of these systems so we can overcome some of the limitations will play a critical role in increasing food production while promoting positive environmental outcomes.

Forage management and environmental conditions affect water soluble carbohydrate (WSC) storage, and, in turn, influence ruminant forage utilization in silvopastoral systems. The objective was to determine effects of four dependent variables: forage species [(non-native, C₃ (orchardgrass (Dactylis glomerata L.)) and native C₄ mix (8:1:1 big bluestem (Andropogon gerardii Vitman), little bluestem (Schizachyrium scoparium Michx. Nash) and indiangrass (Sorghastrum nutans L.))]; fertility (poultry litter and an unfertilized control); forage sampling date (mid-May, late-May, early-June, mid-June, and late-June); and hour of day (0800, 1100, 1400, and 1700 h) on WSC accumulation in a silvopasture. Concentrations of WSC (g kg DM⁻¹) were greater (p ≤ 0.05) for C₃ forages, with poultry litter not impacting WSC accumulation. Overall, WSC was greatest in mid-June, with the lowest WSC concentration observed at 0800 compared to 1100, 1400, and 1700 h (p ≤ 0.05). Therefore, harvesting forages later in the day resulted in greater WSC. A stepwise regression model indicated acid detergent fiber, ash, and forage P concentration were the best predictors (R₂ = 0.85, p ≤ 0.05) of forage WSC. These results may be useful in future studies aimed at explaining diurnal cattle grazing preference and optimum forage harvest timing in silvopastoral systems.

Poultry litter is a widely available fertilizer in the southeast USA and subsurface application of litter can increase both forage production and nutritive value. Frequent rainfall events and high humidity often limit time available for hay curing; baled silage techniques can increase harvest time flexibility. Unfortunately, rainfall events can still occur without forecast during harvest events, resulting in delayed baling or wrapping. The objective of this study was to evaluate poultry litter amendment methods, subsurface (SUB) and surface (SURF), and the effect of no rain (NR) on bales with wrapping after 2 h compared with rained-on bales with 17 h delayed wrapping (RDW) on warm-season grass baleage fermentation and nutritive value. Data were analyzed as a randomized complete block design with two amendment treatments and two post-baling treatments. Crude protein (CP) was greater (p < 0.01) and neutral detergent fiber (NDF) was lower (p < 0.01) in both pre- and post-ensiled bales with subsurface-applied poultry litter. Rain and delayed wrapping resulted in lower pH (p = 0.03), starch (p < 0.01), and water-soluble carbohydrates (p < 0.01) in pre-ensiled bales, compared to those that did not receive rain and were wrapped within 2 h, while post-ensiled bales only differed in lower (p < 0.01) starch and slightly greater (p < 0.01) NDF in RDW. Lactic acid (p < 0.01), acetic acid (p < 0.01), and total acids (p = 0.03) were greater in SUB, while butyric acid tended to be greater (p = 0.09), and alcohols (p = 0.05) were greater in SURF. Bales from RDW and NR only differed by greater (p < 0.01) propionic acid concentrations in NR. Under the conditions of this experiment, subsurface application of poultry litter increased final nutritive value, while rainfall and delayed wrapping of 17 h had few effects on the final nutritive value of warm-season grass baleage.

Forage sorghum is an alternative source for biofuel feedstock production and may also provide forage for livestock operations. Introducing biofuel feedstock as a dual-use forage to livestock operations has the potential to increase the adoption of biofuel feedstock production. However, additional technical agronomic information focusing on tillage, row arrangement, and harvest date for forage sorghum planted into pasturelands intended for dual use is needed. Three tillage treatments, disking and rototilling (RT), chisel plow (CP), and no tillage (NT), and two row arrangement treatments, single-row planting with 76.2 cm rows and twin rows of 17.8 cm on 76.2 cm centers, were tested for effects on forage sorghum yield in a 3-cut system. This study tested two sites in Booneville, AR, from 2010 to 2012. Several interactions with year were detected, likely due to large precipitation differences within and among years. The year greatly affected the yield, with greater (p < 0.05) yields in year 1 compared to years 2 and 3 in both locations. No till resulted in lower yields in some years and harvest dates, though no clear trend was detected among tillage treatments over years. Twin rows generally did not improve yield, except for the third harvest date at one location. No strong trends for tillage or row arrangement effects were observed in this study. Inconsistencies may have resulted from the strong influence of year or interactions of multiple factors, which may challenge producers interested in utilizing forage sorghum for biofuels and livestock feed.

Subsurface poultry litter application improves nutrient utilization compared with surface application through reduced nutrient runoff, and increased forage nutritive value. This study compared the effects of subsurface (SUB) or surface (SURF) poultry litter application against controls (CON; no litter) for baled silages made at high moisture (HM) or low moisture at (LM) Booneville, AR, in 2018. Mixtures of cereal rye (Secale cereale L.), annual ryegrass (Lolium multiflorum Lam.), and tall fescue [Schedonorus arundinaceus (Schreb.) Dumort., nom. cons.] baled silages were compared for nutritive value and silage fermentation characteristics. Data were analyzed as a split‐plot design with three fertilizer treatments as whole plots, and initial bale moisture as subplots. Pre‐ensiled P and K were greater (P < .05) for the mean of SURF and SUB than for CON. Neutral detergent fiber was greater (P = .02) in CON versus the mean of SURF and SUB. In post‐ensiled bales, propionic (P < .05) and succinic acid (P < .05) concentrations were greater in the mean of SURF and SUB than in CON, and greater in SUB than in SURF. Moisture had positive (P < 0.05) relationships with fermentation acids, and negative relationships with pH, water‐soluble carbohydrates, and starch. Overall, very few differences between SUB and SURF were detected, baleage nutritive value was not improved with SUB poultry litter application, and fermentation characteristics were most affected by the initial bale moisture.