Decade‐long persistence, production, and profitability of tall fescue–alfalfa mixtures and nitrogen‐fertilized tall fescue

Limited work has been done to develop organic forage programs in humid subtropical regions despite growing demand for high‐value forage and organic products. Alternative crops were compared for optimizing forage production and nutritive value under organic conditions in the southeastern United States. The study was conducted at the Middle Tennessee AgResearch and Education Center, in Spring Hill, Tennessee. Forage treatments consisted of (a) monoculture tall fescue [Schedonorus arundinaceus (Schreb.) Dumort.], (b) monoculture bermudagrass [Cynodon dactlyon (L.) Pers.], (c) tall fescue and alfalfa (Medicago sativa L.) mixture, (d) bermudagrass and alfalfa mixture, and (e) an annual rotation of winter wheat (Triticum aestivum L.) mixed with winter pea (Pisum sativum L.) followed by sorghum–sudangrass [Sorghum bicolor (L.) Moench x S. sudanese (Piper) Stapf.] mixed with cowpea [Vigna unguiculata (L.) Walp.] mixture. Perennial treatments were established during the 2017–2018 growing season. Monthly production was measured in the 2018–2019 and 2019–2020 growing seasons. Botanical composition of forage mass fluctuated due to establishment dynamics and weed competition, affecting forage quantity and quality. The annual rotation was the highest‐yielding treatment, producing more than 6,000 kg−1, though each tall fescue and tall fescue–alfalfa treatments produced ∼4,000 kg ha−1. Nutritive value was sufficient for most livestock operations, with forage crude protein concentration averaging ∼150 g kg−1 across treatments and growing seasons. For transitioning organic producers, a perennial forage will likely favor long‐term sustainability, whereas the annual rotation may be useful during the transition period to reduce weed pressure before transitioning to a perennial forage system.

Tall fescue (Festuca arundinacea Schreb.) is an excellent perennial grass for spring and fall forage production and for erosion control on sloping land. Tall fescue forage production is poor during the summer, however. Our objective was to improve pasture productivity without increasing erodibility by planting a sorghum x sudan hybrid [Sorghum bicolor (L.) Moench x Sorghum bicolor L. Moench] (S x S) or grain sorghum [Sorghum bicolor (L.) Moench] (GS) in 12 in. killed strips of tall fescue and to determine if strips could be used in subsequent years without additional herbicide treatment. Forage from a block of tall fescue was harvested in May 1990, and plants were allowed to regrow for 1 wk before application of glyphosate in 12 in. strips on 30 in. centers at two rates of 1.2 and 0.6 Ib ai/acre (strip-kill). For control treatments, the entire tall fescue sod was killed (complete-kill) or tall fescue was not sprayed in order to measure forage production from the grass monoculture. The S x S (cv. FFR 201) was planted into strip-kill and complete-kill plots 1 wk after glyphosate treatment in 1990 and again in 1991 and 1992 without additional glyphosate treatment. In May 1991, GS (cv. MFA GS-10) was planted into strip-kill and complete-kill plots and these strips were used again in 1992. Tall fescue was successfully killed with a single application of each rate of glyphosate in the strip-kill and complete-kill systems. There was little difference in S x S dry matter yield or GS grain yield between glyphosate treatments. Dry matter yield of S x S in strip-kill plots decreased each year after initial treatment in 1990, probably a result of increased competition from tall fescue encroachment into the killed strips. Dry matter yield of S x S in strip-kill plots was 16, 49, and 52% less than that of the complete-kill plots in 1990, 1991, and 1992, respectively. Tall fescue yield in strip-kill plots was only slightly less than that of tall fescue (monoculture) control plots. Total forage yield (S x S plus tall fescue) in the strip-kill plots was 3.49, 2.39, and 1.63 tons/acre greater than that of the tall fescue (monoculture) control in 1990, 1991, and 1992, respectively. Grain sorghum yield in strip-kill plots was 25 bu/acre less than that in complete-kill plots in 1991 and 53 bu/acre less than that in complete-kill plots in 1991. Planting S x S into the same strip-kill plots is feasible for 3 yr, however for GS to be successful in a strip-kill system, tall fescue strips must be killed annually.

Stockpiled tall fescue [Lolium arundinaceum (Schreb.) Darbysh.] is an alternative to extend the grazing season and reduce feeding costs during the winter. In addition, adequate fertility management with N, P, and K nutrients can improve forage production. Our objective was to evaluate the impact of N, P, and K fertilization (from 0 to 120 lb/a, 0 and 50 lb/a, and 0 and 30 lb/a, respectively) on forage accumulation (FA) and nutritive value in stockpiled tall fescue in claypan soils. The study was carried out in Columbus, KS, on established ‘Kentucky 31’ tall fescue pastures in the fall of 2019 and 2021 (two years). The treatments were one unfertilized control and fertilization with six combinations of nitrogen (0, 40, 60, 80, and 120 lb/a), phosphorus (0 and 50 lb/a), and potassium (0 and 30 lb/a) rates. Forage accumulation was greater in the treatments with at least 60 lb N/a compared with the unfertilized control (1,235 vs. 570 lb DM/a). However, the greatest crude protein content (CP; 13%) and crude protein accumulation (CPA; 163 lb CP/a) were produced when 120 lb N/a was applied. Nitrogen fertilization also resulted in greater total digestible nutrients, net energy gain, net energy maintenance, and lower acid detergent fiber. Phosphorus and potassium had little effect on the measured responses. Nitrogen fertilization can be an alternative to increase stockpiled tall fescue FA and nutritive value, reducing the need for energy and protein supplementation of livestock during the winter.

In order to utilize alfalfa (Medicago sativa L.), alone or in mixtures with grasses, defoliation management practices must be evaluated to assess their performance. The objective was to determine the forage accumulation (FA) and nutritive value of alfalfa grown as a monoculture (ALF) and in mixtures with tall fescue [Lolium arundinaceum (Schreb.) Darbyish] (ATF) or bermudagrass [Cynodon dactylon (L.) Pers] (ABG) subjected to four harvest intervals (clipped every 21, 28, 35, and 42 d). The study was conducted in Crossville, TN, and Charleston, OH, during the 2016 and 2017 growing seasons, and in Salisbury, NC, during the 2017 and 2018 growing seasons. Harvest intervals of 35 d or greater showed optimal FA, with greatest productivity in spring. In summer, the plot productivity of ATF was not different from ABG. The ATF mixture was superior to ABG in FA for the entire season. Although tall fescue can be very competitive with alfalfa in mixtures, it results in greater FA while reducing weed competition. Botanical composition indicated greater weed infestation in ALF than in mixtures. Growing alfalfa–grass mixtures can increase sward crude protein compared with grass monocultures (average of 128 g kg–1 for ATF and 161 g kg–1 for ABG). We conclude that harvest intervals of 35 d or longer should be adopted to provide greater FA, and the ALF and ATF treatments resulted in superior FA compared with ABG in the southern United States.

Research on the use of forages to transition cropland to organic production is limited. Our objective was to determine the cost of transitioning from conventional to organic production using perennial and annual forage systems. The study was conducted at the Middle Tennessee AgResearch and Education Center, in Spring Hill, TN. Five forage treatments were compared: tall fescue [Schedonorus arundinaceus (Schreb.) Dumort.] monoculture, bermudagrass [Cynodon dactlyon (L.) Pers.] monoculture, tall fescue and alfalfa (Medicago sativa L.) mixture, bermudagrass and alfalfa mixture, and an annual rotation of a cool‐season mixture, including winter wheat (Triticum aestivum L.) and winter pea (Pisum sativum L.), and a warm‐season mixture of sorghum–sudangrass [Sorghum bicolor (L.) Moench × S.orghum sudanese (Piper) Stapf] and cowpea [Vigna unguiculata (L.) Walp.]. Perennial forages were established in 2017 and 2018 following orchard removal and a fallow period. Regular production measurements began in 2019 when the plots achieved full organic certification status. Tall fescue had the lowest cost for the overall transition period. However, on a cost per unit of dry matter (DM) forage mass and on a cost per unit of crude protein (CP) basis, all treatments were similar, with a range between US$0.02 and $0.03 lb–1 for DM forage mass and between $0.15 and $0.20 lb–1 for CP, except for the more costly bermudagrass monoculture that was $0.06 lb–1 DM forage mass and $0.40 lb–1 CP. Given the lack of a premium during the transition period, tall fescue was the most cost‐effective transition forage.

Thompson, D. J. 2013. Yield and nutritive value of irrigated tall fescue compared with orchardgrass: in monocultures or mixed with alfalfa. Can. J. Plant Sci. 93: 799-807. Orchardgrass (Dactylis glomerata L.) is commonly grown for irrigated forage production in interior British Columbia. Tall fescue [Schedonorus phoenix (Schop.) Holub.] is also adapted to the area but no comparative trials have been reported. Three varieties of each grass species were grown in monocultures or in mixtures with alfalfa at three irrigated sites throughout southern interior British Columbia. Study objectives included comparing the forage yield and nutritive value of the following groups: (1) tall fescue and orchardgrass monocultures, (2) tall fescue and orchardgrass mixtures with alfalfa and (3) grass-alfalfa mixtures with monocultures. In monoculture, tall fescue yield was 9% greater than orchardgrass (significantly greater yield at 3 of 6 site-years), though forage nutritive values were similar. Mixtures of the two grasses ...

We determined if sequence of ingestion affected use of endophyte-infected tall fescue (TF) when cattle also grazed birdsfoot trefoil (BFT) or alfalfa (ALF). Based on chemical characteristics of TF (alkaloids), BFT (tannins), and ALF (saponins), we hypothesized that cattle first allowed to graze ALF or BFT would subsequently spend more time grazing TF than cattle that first grazed TF followed by ALF or BFT. Sixteen bred heifers (478 ± 39 kg initial BW) were randomly assigned to 4 replicated pasture units. Each replicated unit consisted of 4 treatment sequences (TF → BFT, TF→ALF, BFT → TF, or ALF→TF), with 2 cows per sequence. Pastures were in the vegetative stage of growth at a height of 20 to 30 cm and provided ad libitum forage to cattle. We recorded foraging on TF, BFT, and ALF using scan sampling of individuals at 2-min intervals. The study was conducted in 4 phases run sequentially, for a total of 30 d. In phases 1 and 3, cattle in group 1 grazed TF pastures for 45 min and were then moved to BFT pastures for the next 45 min (TF→BFT); cattle in group 2 grazed in the reverse sequence (BFT → TF). In phases 2 and 4, cattle in group 1 grazed TF pastures for 45 min and then subsequently grazed ALF pastures for the remaining 45 min (TF→ALF); cattle in group 2 grazed in the reverse sequence (ALF→TF). Sequence of plant ingestion affected food selection. In phase 1, scans revealed grazing of TF by heifers was cyclic, and heifers tended to have more scans (P = 0.52) grazing TF when they grazed BFT → TF; scans for heifers grazing TF were consistently greater (P < 0.05) throughout phase 3 of the trial. In phase 2, heifers that grazed in the sequence ALF→TF spent considerably more scans (P = 0.03) foraging on TF from d 4 to 10 than heifers that grazed in the sequence TF→ALF, and they remained greater throughout phase 4 of the trial. Although the sequence ALF→TF appeared to be more effective than BFT → TF, consistent with the hypothesis of a complementary relationship between the steroidal alkaloids in TF and saponins in ALF, tannin concentrations in BFT were minimal (1.8%), which likely reduced the presumed inactivation of alkaloids by tannins. We also speculate that heifers needed to learn about the positive postingestive influence of sequence, a notion consistent with more similar scans spent foraging BFT and TF early in phases 1 (BFT → TF) and 2 (ALF→TF), and with the consistent and marked increase in scans spent foraging on TF for animals foraging in phases 3 (BFT → TF) and 4 (ALF→TF).

Cattle feeding in South Korea has been heavily dependent on domestically produced rice straw and imported grain. Around 42% of domestically produced rice straw is utilized for forage, and the remainder is recycled to restore soil fertility. Approximately 35% of round baleages were made with rice straw. However, higher quality hay is desired over rice straw. Due to increasing stockpiles of rice, there has been an economic burden on the government to store the surplus; therefore production of annual forage crops in rice fields has been further promoted in recent years. Hay import from the USA currently constitutes more than 80% of total imported hays. The main imported hays are alfalfa (Medicago sativa), timothy (Phleum pretense), and tall fescue (Festica arundinacea). The estimated forage required for cattle feeding was approximately 5.4 million MT in 2016. Domestically produced forage sates only 43% of that value, while low quality rice straw and imported hay covered the rest of demand by 33% and 20%, respectively. As utilization of domestically produced forage is more desirable for forage-based cattle production, long-term strategies have been necessary to promote domestic production of high quality baleage. One such strategy has been utilizing the fertile soil and abundance of fallow rice fields of western region of S. Korea to produce forage crops. Italian ryegrass (Lolium multiflorum) is the most successfully produced winter annual in the region and is approximately 56% of the total winter annual forage production. Forage sorghums (Sorghum bicolor), sorghum × sudangrass hybrids, and hybrid corn (Zea mays) produce a substantial amount of warm-season forage during summer. Produced forage has been largely stored through baleage due to heavy dew and frequent rains and has been evaluated according to S. Korea’s newly implemented baleage commodity evaluation system. The system weighs 50% of its total grading points on moisture content because of its importance in deliverable DM content and desirable baleage fermentation; this has proved to be an effective method. Although further improvement is required for the future of forage production in South Korea, the current government-led forage production in rice fields has been able to alleviate some of the country’s shortage for quality hay.

Persistence and productivity of grazing-tolerant «Alfagraze» alfalfa (Medicago sativa L.) grown with endophyte-free tall fescue (Festuca arundinacea Schreb.) is not well known. Our primary objectives were to determine yield and persistence of the grass and legume in mixture and monoculture with and without N fertilizer at three Georgia locations over 3 yr. Small-plot field experiments with four replications harvested at 4-wk intervals were conducted at Blairsville in the mountains on a Clifton clay loam (clayey, mixed, mesic Typic Hapludults) and at Eatonton in the lower Piedmont on a Davidson loam (clayey, kaolinitic, thermic, Humic Paleudult). The five treatments were «AU Triumph» tall fescue with 0 N; tall fescue with 50 lb N/acre in September, February, and April; tall fescue and Alfagraze alfalfa with 0 N; tall fescue + alfalfa with 50 lb N/acre in February; and alfalfa alone, all harvested at 4-wk intervals. At Athens in the Piedmont on Cecil sandy clay loam (clayey, thermic, kaolinitic Typic Hapludult) the same treatments were harvested at 3-, 4-, and 6-wk intervals. Alfagraze alfalfa persisted well and was productive in mixture with AU Triumph tall fescue with 0 N, averaging about 8000 lb/acre dry forage at the three locations when cut at 4-wk intervals over 3 yr. During the third year, alfalfa constituted 50 % or more of the mixture by estimate at 4- and 6-wk cutting invervals and greater than 25 % at the 3-wk interval with no additional N fertilizer. Alfalfa monoculture and tall fescue-alfalfa mixtures without N fertilization had similar annual yields, which were superior to grass monoculture with 150 lb N/acre except at Athens where unfavorable soil conditions hindered alfalfa growth. Nitrogen fertilization (50 lb N/acre) of mixtures increased total yield but did not affect percentage alfalfa in the forage. Summer production of alfalfa was superior to tall fescue. Results suggest that Alfagraze alfalfa adequately fertilized with P and K can be successfully grown with endotype-free tall fescue when harvested at 3- to 4-wk intervals, suggesting good persistence under rotational stocking with livestock

Alfalfa-grass mixtures reduce greenhouse gas emissions and net global warming potential while maintaining yield advantages over monocultures

Simple SummaryThis study was carried out to investigate the nutrient compositions of alfalfa, tall fescue and tall fescue + alfalfa mixed grassland under different mowing stubble times and clarify their correlation with in vitro digestibility. In vitro dry matter digestibility of alfalfa, tall fescue and tall fescue + alfalfa were predicted by their nutrient composition respectively. The results demonstrated that these models based on nutrient composition could accurately predict the in vitro dry matter digestibility of alfalfa monoculture, tall fescue monoculture and alfalfa + tall fescue mixture, respectively, and provide a forage utilization mode for sown pasture.Mowing, Mowing, which affects the nutritional levels of grasslands, is the main utilization of sown pasture. We sowed alfalfa monoculture grassland, tall fescue monoculture grassland and tall fescue + alfalfa mixed grassland in typical steppe of the Loess Plateau to investigate the nutrient compositions and in vitro degradability of those three grasslands under different mowing stubble times and to provide reference for nutrient management of sown pastures. The results showed that the stubble time significantly affected (p < 0.05) the nutrient compositions and mineral elements of forages in alfalfa monoculture grassland, whereas had no effects on the nutrient compositions and dry matter digestibility of forages in tall fescue monoculture grassland and alfalfa + tall fescue mixed grassland. The relative feeding value of mixed grassland of alfalfa and tall fescue was increased by 2.6–22.4% as compared to monoculture grasslands. The model constructed based on forage nutrient content could accurately predict the forage dry matter degradability of alfalfa monoculture, tall fescue monoculture and mixed alfalfa and tall fescue, respectively.

Forage species composition influenced soil health in organic forage transitioning systems

Binary grass–legume mixtures can benefit forage production systems in different ways helping growers cope both with increasing input costs (e.g., N fertilizer, herbicides) and potentially more variable weather. The main objective of this study was to evaluate alfalfa (Medicago sativa L.) and tall fescue [Schedonorus phoenix (Scop.) Holub] mixtures across a wide range of environments to assess herbage accumulation, weed suppression and fertilizer nitrogen replacement values (FNRV). A common field experiment was established in 2009 and 2010 at six study sites in the United States: Maryland, Pennsylvania, Utah, Virginia, Wisconsin, and Wyoming. Experimental treatments included an alfalfa monoculture, three alfalfa–fescue mixtures with seed ratios of 75:25, 50:50, and 25:75 of alfalfa/tall fescue, and tall fescue monocultures that received nitrogen applications of 0, 50, 100, 150, 200, and 300 kg N ha–1, respectively. Data were collected over a 2‐yr period. The responses of tall fescue monocultures to N fertilization differed among sites, and this contrasted with mixture yields, which did not exhibit site × treatment interactions (P &gt; 0.05). Herbage accumulation and weed suppression were consistently higher in mixtures compared with alfalfa monocultures and tall fescue monocultures receiving less than 100 kg N ha–1. The FNRVs for alfalfa were within the range reported for other studies and averaged 143 kg N ha–1. The consistent herbage accumulations across these multiple environments suggest binary mixtures of alfalfa–tall fescue may be a good option for many forage–livestock producers although yields could be improved with location specific cultivar selection.

Pasture‐based dairy operators usually aim to optimize defoliation intensity to maximize forage production and nutritive value. The objective was to determine forage accumulation, nutritive value, and tiller density of tall fescue [Lolium arundinaceum (Schreb.) Darbysh.] and perennial ryegrass (L. perenne L.) when repeatedly mowed to a stubble height of 2.5, 5, 7.5, 10, 12.5, or 15 cm. In a 2‐yr study conducted near Columbia, MO, plots were mown to their respective stubble height whenever they grew to a “trigger” height of 20 to 22 plate meter units (approximately 4000 kg ha−1 dry matter [DM] to soil surface). In Year 1, tall fescue mowed to 2.5 cm accumulated 14,440 kg ha−1 which was the most of any treatment. In Year 2, forage accumulation for tall fescue mowed to 2.5, 5, or 7.5 cm did not differ, but was approximately 15% more than perennial ryegrass mowed to the same heights. For both species, forage harvested at stubble heights ≥10 cm had greater nutritive value than at heights of ≤7.5 cm. Perennial ryegrass had 60% fewer tillers for stubble heights ≤7.5 cm compared to heights ≥10 cm. Tall fescue showed no difference in tiller density for any stubble height. Milk production ha−1, predicted via MILK2006, was greater for stubble heights ≤7.5 cm, primarily due to greater forage accumulation. This study showed that tall fescue is better suited than perennial ryegrass for pasture‐based dairies in the Midwest because of its greater forage yield, estimated milk production, and stand (tiller) density.

Alfalfa (Medicago sativa L.) is an important forage legume grownin Kansas, USA and its productivity with cool-season grasses however is unknown.The objective of this study was to determine the dry matter yield (DMY) andforage nutritive value of alfalfa-grass mixtures compared to those of alfalfaand grasses grown in monoculture with and without nitrogen fertilization. Threedifferent alfalfa varieties were planted (reduced-lignin alfalfa, Roundup Ready,and conventional alfalfa) and two kinds of cool-season grasses (smooth brome,Bromus inermis Leyss, and tall fescue, Festucaarundinacea Schreb) were planted as a monoculture or inalfalfa-grass mixtures. Nitrogen fertilizer (urea) was applied at green-up at arate of 56 kg/ha and after the second cutting at a rate of 56 kg/ha in 2016 and2017, respectively. and control treatments received no nitrogen. DMY wassignificantly higher in monoculture alfalfa and alfalfa-grass mixtures than ingrass monocultures. Between alfalfa monoculture and alfalfa-grass mixtures, nosignificant differences in DMY were found. For all treatments, nitrogenapplication significantly increased DMY compared to the control. In 2016 and2017, the low-lignin alfalfa monoculture had the lowest acid detergent fiber(ADF) and the grass monocultures had the highest ADF. In 2016 and 2017, neutraldetergent fiber (NDF) in smooth bromegrass and tall fescue was higher than inother species treatments. A low-lignin alfalfa monoculture had significantlylower NDF concentration compared to alfalfa-grass mixtures. When averaged over2016 and 2017, relative feed value (RFV) was highest in low-lignin alfalfa andlowest in the grass monocultures. In both years, nitrogen fertilizer applicationdid not affect nutritive values.