Forage: Research Projects


Forage Management

Link Pointer Harvest Interval Effects on the Persistence and Productivity of Alfalfa Grown as a Monoculture or in Mixtures in the Southeastern United States
For alfalfa (Medicago sativa L.) to be profitable in the southeastern United States, enhanced persistence is required.

Link Pointer Forage Warm-Season Legumes and Grasses Intercropped with Corn as an Alternative for Corn Silage Production
The purpose of this study was to determine the yield and nutritive value potential of warm-season annual forages intercropped with corn (Zea mays L.) for silage production. Intercropped forages can be harvested and ensiled with corn for silage production or can be left with the corn residue after harvesting to be grazed on in integrated crop-livestock systems.

Link Pointer Influence of Height-Based Management on Forage Nutritive Value of Four Warm-Season Forage Grasses
Harvest timing is an influential factor in providing animals with high quality forage. Height-based management is commonly practiced to determine timing of cutting or grazing. This study aimed to observe nutritive value changes in tall- and short-growing warm-season grasses with repeated cuttings.

Link Pointer Forage Nutritive Value and Herbage Mass Relationship of Four Warm-Season Grasses
To provide animals with high quality forage, practical methods are needed to estimate nutritive value to optimize harvest timing. The objective of this study was to develop such models to estimate warm-season forage nutritive value in the southeastern United States.

Link Pointer Utility of Aminocyclopyrachlor for Control of Horsenettle and Tall Ironweed in Cool-Season Grass Pastures
Because horsenettle and tall ironweed are difficult to control in cool-season grass pastures, research was conducted in Tennessee and Kentucky in 2010 and 2011 to examine the efficacy of aminocyclopyrachlor on these weeds.

Link Pointer Influence of Aminocyclopyrachlor Plus Metsulfuron on Seed Head Development and Forage Quality in Tall Fescue
When applied alone or in combination with MAT28 or aminopyralid, metsulfuron reduced seed heads and improved forage quality in tall fescue, but also caused injury and reduced spring yield. Also, metsulfuron applied alone or in combination with MAT28 or aminopyralid reduced total ergot alkaloid concentration and therefore can potentially reduce the severity of fescue toxicosis.


Native Grasses

Link Pointer Continuous Grazing of Mixed Native Warm-season Grass in the Fescue Belt
Continuous, season-long (May–August) grazing is the most commonly used grazing strategy among tall fescue belt beef producers. However, little information is available regarding the feasibility of managing native warm-season grass pastures in this region with continuous, season-long grazing. We compared stand sustain-ability, beef cattle performance, and pasture production between continuous, season-long grazing and heavy-early, a modified continuous grazing strategy, on mixed-pastures.

Link Pointer Evaluation of Eastern Gamagrass and a Sorghum × Sudangrass for Summer Pasture
Improved summer forage production is important in forage systems dominated by cool-season perennial grasses. Improved forage may be especially important for heifer development. Therefore, we compared two summer forage options, a perennial, eastern gamagrass, and a widely used summer annual, sorghum × sudangrass hybrid, as options for providing summer pasture for bred heifers.

Link Pointer Overseeding Cool-Season Annual Grasses into Dormant Lowland Switchgrass Stands
Improved use of the land resource used to grow switchgrass, whether for biomass or forage production, could be achieved by dormant-season overseeding with cool-season annual grasses.

Link Pointer Evaluation of Eastern Gamagrass and a Sorghum × Sudangrass for Summer Pasture
Improved summer forage production is important in forage systems dominated by cool-season perennial grasses. Improved forage may be especially important for heifer [Bos taurus (L)] development.Producers within the transition zone should consider use of these forages as a complement to their cool-season forage base, especially the more cost-effective perennial.

Link Pointer Improving Nutritive Value of Native Warm-Season Grasses with the Plant Growth Regulator Trinexapac-Ethyl
Gibberellin inhibitors can alter plant regrowth and forage value. This study assessed the impact of trinexapac-ethyl [TE; ethyl 4-(cyclopropyl-hydroxymethylene)- 3,5-dioxo-cyclohexane-1-carboxylate] on fall NWSG forage. Application of TE occurred in late July at four levels (0, 0.3, 0.6, and 1.2 kg a.i. ha–1) to switchgrass (SG; Panicum virgatum L.) and a mixed sward (BBIG) of big bluestem (Andropogon gerardii Vitman) and indiangrass (Sorghastrum nutans L.) during 2016 and 2017.

Link Pointer Management of Native Warm-Season Grasses for Beef Cattle and Biomass Production in the Mid-South USA
Native grasses, such as switchgrass, big bluestem, indiangrass, and eastern gamagrass may be capable of providing desirable summer forage for cattle as well as a source of biomass for renewable energy.

Link Pointer Forage Harvest Timing Impact on Biomass Quality from Native Warm-Season Grass Mixtures
Biomass production systems using native warm-season grasses can allow for an early-season harvest (for forage) followed by a dormant harvest (for biomass). This study was conducted to investigate the impact of harvest timing and grass species on the chemical composition of harvested forage and biomass.

Link Pointer Biomass and Integrated Forage/Biomass Yields of Switchgrass as Affected by Intercropped Cool- and Warm-Season Legumes
Switchgrass has potential as a biofuel feedstock for ethanol production on marginal soils not suitable for row crop production. Further, it is hypothesized that legumes may be interseeded into switchgrass to increase available soil nitrogen (N) and enhance switchgrass yields. Therefore the primary objective was to identify compatible legume species for intercropping with lowland switchgrass and determine if biomass yields and forage quality can be improved.

Link Pointer The Cost of Feeding Bred Dairy Heifers on Native Warm-Season Grasses and Harvested Feedstuffs
The objectives of this research were to determine the cost of feeding bred dairy heifers grazing native warm-season grasses (NWSG), with and without legumes, and compare the cost of grazing with the cost of rearing heifers using 3 traditional rations. The 3 rations were corn silage with soybean meal, corn silage with dry distillers grain, and a wet distillers grain-based ration. Results of this study suggest that SG was the most cost-effective NWSG alternative to harvested feeds for bred dairy heifer rearing.

Link Pointer Switchgrass Yield and Stand Dynamics from Legume Intercropping Based on Seeding Rate and Harvest Management
Intercropping legumes may reduce inputs and enhance sustainability of forage and feedstock production, especially on marginal soils. This approach is largely untested for switchgrass production, yet producer acceptance should be high given the traditional use of legumes in forage/agricultural systems. Intercropping selected legumes in switchgrass may enhance forage quality and yield while reducing nonrenewable inputs, fertilizer costs, and emissions/runoff to air and groundwater.

Link Pointer Dormant-Season Planting and Seed-Dormancy Impacts on Switchgrass Establishment and Yield
Establishment failures linked to seed dormancy are a challenge to wide-scale use of switchgrass (Panicum virgatum L.) for biomass feedstock and forage production. One prospective strategy for breaking dormancy is dormantseason planting.

Link Pointer Displacing Inorganic Nitrogen in Lignocellulosic Feedstock Production Systems
Legume intercrops (partridgepea) and biochar may supply analogous N to synthetic fertilizers, thereby displacing inorganic N without altering feedstock quality. However, for inorganic N alternatives to be competitive on a break-even cost basis, greater biomass yields need to be obtained under these management practices.

Link Pointer Breakeven Price of Biomass from Switchgrass, Big Bluestem, and Indiangrass in a Dual-Purpose Production System in Tennessee
Producers considering a dual-purpose production system for NWSGs will be confronted with several complex decisions about how to manage yield, quality, and cost of replacing nutrients while maximizing profits.

Link Pointer The Impact of Harvest Timing on Biomass Yield from Native Warm-Season Grass Mixtures
With increased harvest opportunities native warm-season grasses, grown in the mid-South United States under a dual-harvest system, can increase harvest options for producers by supplying acceptable forage yield for both early harvests and still provide biomass production.


Fertilization

Link Pointer Utilization of Spent Microbial Biomass as an Alternative Crop Nitrogen Source
Spent microbial biomass (SMB), a nutrient-rich co-product of industrial white biotechnology processes, is produced in substantial quantities alongside high-value products and most often disposed of in landfills or incinerated. Alternatively, SMB could be reused as a land-applied N source in agricultural crop production, reducing the environmental and economic footprint of synthetic fertilizers. This research compares SMB applied at different rates to current farmer practice (FP) fertilizer use in tall fescue (Festuca arundinacea Schreb.) and corn (Zea mays L.) production.

Link Pointer Alternatives to Conventional Nitrogen Fertilization on Tall Fescue and Bermudagrass
Alternatives to conventional N fertilization on tall fescue and bermudagrass were studied at the University of Tennessee. The objective of this study was to evaluate the effect of different sources of N, to include two perennial and one annual legume species, on HM and forage nutritive value of tall fescue and bermudagrass pastures.

Link Pointer Nitrogen Rate and Initiation Date Effects on Stockpiled Tall Fescue During Fall Grazing in Tennessee
In Tennessee, N is one of the most common limiting nutrients for tall fescue production. Rising prices for N fertilizer have pressured cow-calf producers in Tennessee to reevaluate N management alternatives. The objectives of this study were to determine the effect of initiation date and N fertilization on stockpiled tall fescue yield, nutritive value, animal performance during fall grazing, and overall profitability of the production system.

Link Pointer Forage Performance and Soil Quality in Forage Systems under Organic Management in the Southeastern United States
Interest is increasing in organic forage production and sod-based rotations in the southeastern United States, but research-based information is limited. A replicated field study was established to evaluate productivity and soil quality changes in five organically managed forage systems.

Link Pointer Cultivar and Phosphorus Amendment Impacts on Organically Managed Forage Cowpea Yield and Composition
Cowpea is a warm-season legume with many traits that make it an attractive forage or cover crop for organic systems. Eight cowpea cultivars were evaluated under organic management at two locations for stand establishment, forage yield and quality, and weed biomass.