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Many cool-season pastures in the southeastern U.S. are dominated by a competitive cool-season grass, tall fescue (Schedonorus arundinaceus), and lack substantial plant diversity. Planting native warm-season grasses (NWSGs) and wildflowers (WFs) into these pastures could provide summer forage for cattle and more floral resources for pollinators. This paper summarizes field experiments designed to evaluate different spatiotemporal planting arrangements of NWSGs and WFs to improve their establishment success. The study was conducted from April 2021 to October 2023 in central Virginia (USA). Planting treatments included NWSG and WF mixtures planted: (1) together in the same space, (2) spatially separated in space (i.e., side by side), or (3) temporally separated where NWSGs and WFs were planted in difference sequences. Results showed few differences in forage mass, floral production, and botanical composition as well as stand density in 2021 and 2022. In 2023, NWSG abundance was greater where grasses were planted first or mixed with WFs. Similarly, the WF component was favored when they were planted before NWSGs. Overall, planting NWSG and WF mixes separately, either spatially or temporally, favors successful establishment and could offer more flexibility for using selective herbicides to suppress the heavy weed pressure that often accompanies these plantings. [ABSTRACT FROM AUTHOR]

The influences of legume diversification on soil carbon (C) pools and sequestration, particularly in Himalayan pastureland, remain poorly understood. Moreover, the impact of legume diversification activities and the stoichiometry of soil enzymes in C biogeochemistry at the ecosystem level remains largely overlooked. The purpose of this study is to investigate the influences of legume diversification on activities and the stoichiometry of soil enzymes and their control of C sequestration in pasturelands. Four experimental fertilized species combinations, namely, SG (50% Festuca arundinacea + 50% Dactylis glomerata), SGL1 (25% Festuca arundinacea + 25% Dactylis glomerata + 50% Onobrychis viciifolia), SGL2 (25% Festuca arundinacea + 25% Dactylis glomerata + 50% Trifolium pratense), SGL12 (25% Festuca arundinacea + 25% Dactylis glomerata + 25% Onobrychis viciifolia + 25% Trifolium pratense), and natural pasture (NG) were compared. Soils under SGL1, SGL2, and SG12 had ~18, 36, and 22% greater soil C than SG, respectively. Among the pastures with fertilization, the C mineralization was suppressed by legume diversification. C sequestration under SGL1, SGL2, and SG12 was ~27, 22, and 38% higher than SG, respectively, at the 0–30 cm soil layer. The ratios of DHA are as follows: for PhOX and DHA, PerOX significantly decreased with an increasing grass–legume mixture, suggesting greater C sequestration. PCA analysis revealed that C sequestration under legume diversification and enzymatic stoichiometry had an indirect but substantial impact on C sequestration. The increasing C sequestration under SGL12 was complemented by higher productivity. Data suggested that increasing legumes in pastureland might greatly enhance ecosystem functions such as soil C storage, productivity, ecorestoration efficiency, and biological activity in Indian Himalayan pastureland. [ABSTRACT FROM AUTHOR]

An on-farm participatory study was undertaken to assess changes over seasons on the availability, botanical and morphological composition, and nutritive value of herbage from two pastures in small-scale dairy systems in the highlands of central Mexico. One pasture (TF-33) was originally sown with tall fescue, while the second pasture (KY) was naturally invaded by Kikuyu grass; both associated with white clover and over-sown in winter with annual ryegrass. Sampling was every 28 days for a year. Variables were sward height, net herbage accumulation, soil cover, tiller density, chemical composition, and in vitro digestibility. A split-plot design was used. Sward height was greater for KY. There were no differences (p > 0.05) for herbage accumulation. TF-33 was 53% live tissue, 30% dead tissue, and 17% other plant material, whilst KY was 50% live tissue, 30% dead tissue, and 18% other plant material. TF-33 showed a higher leaf to stem proportion, while stem was higher in KY. Kikuyu grass and annual ryegrass performed better when associated with TF-33 than in KY pasture. Seasonal changes significantly affected sward height, herbage mass and net herbage accumulation, whereby TF-33 performed better than KY in winter. The multispecies association of diverse grasses and legumes may be complementary at different times of the year due to plasticity among species, and is a feasible option for small-scale dairy systems. [ABSTRACT FROM AUTHOR]

This article represents the perspective of one retired, academic forage breeder and cultivar developer after 50 years of working experience. Developing cultivars that help farmers within pastoral agriculture is the main goal, a system where livestock is the consumer. International Grassland Congress proceedings, as well as the general literature, are historical guides for the state of forage breeding. Efficiency was achieved through technologies; better equipment for planting and harvesting; and advances in computer computation and communication. Biotechnology achievements were fitful and continue to evolve. Cultivar performance mean‐reversion, cost to the program, and what the farmer seed buyer was willing to pay are important considerations for applying any technology, especially biotechnologies. Biotech promises were too optimistic. This was due, in part, to a lack of understanding that traditional phenotypic/genotypic field selection programs operate in a complex way with multiple species and several traits screened simultaneously at a modest cost. The majority of current forage cultivars are from field‐based selection. Industry participation at scientific conferences declined over time, with less sharing of information the result. Cultivar developers will continue using basic field selection methods but should explore applying any technology; just be clever on when, how, and with whom to use them. Practical advice and experiences are also presented and discussed. [ABSTRACT FROM AUTHOR]

The agricultural soils of West Limerick, Ireland, contain very localised, extremely high natural Se concentrations that reach levels that are very toxic to grazing livestock. The Carboniferous shales that formed in anoxic deep-water marine environments are the source of the selenium, which, along with the other redox-sensitive elements of molybdenum, uranium, arsenic and vanadium, were mobilised and reprecipitated in post-glacial anoxic marshes. The result has been a history of selenosis and molybdenosis in livestock in this important dairy province. Soils collected at 10–20 cm from five different agricultural sites were analysed, and all yielded concentrations greatly in excess of the safe Se limits of 3–10 mg kg−1; the highest value recorded was 1265.8 mg kg−1 Se. The highest recorded value for Mo in these soils was 1627.5 mg kg−1, and for U, 658.8 mg kg−1. There was a positive correlation between Se, Mo U and organic matter in the soils. Analysis of non-accumulator pasture grasses (Lolium perenne (perennial ryegrass), Festuca arundinacea (tall fescue), Dactylis glomerata (cocksfoot) and Phleum pretense (timothy grass)) revealed the shoot/leaf to contain up to 78.05 mg kg−1 Se while Trifolium repens (white clover) leaves contained 296.15 mg kg−1 Se. An in situ growing experiment using the Se accumulator species Brassica oleracea revealed 971.2 mg kg−1 Se in the leaves of premier kale, which also contained 1000.4 mg kg−1 Mo. Translocation factors (TFs) were generally higher for Mo than Se across all plant species. Combined X-ray absorption near edge spectroscopy (XANES) with micro-X-ray fluorescence (μ-XRF) showed the Se was present in the soil predominantly as the reduced immobile phase, elemental Se (Se0), but also as bioavailable organoselenium species, mainly selenomethionine (SeMet). SeMet was also the main species identified within both the Se non-accumulator and Se accumulator plants. The Se soil–plant system in West Limerick is dominated by SeMet, and uptake into the cattle pasture results in selenosis in the grazing dairy herds. The hyperaccumulating Brassica oleracea species could be used to extract both the Se and Mo to reduce the toxicity of the blighted fields. [ABSTRACT FROM AUTHOR]

Aphids are major pests of cereal and pasture grasses throughout the world, vectoring disease and reducing plant production. There are few control options other than insecticides. Epichloë endophytes that produce loline alkaloids in their hosts provide a possible mechanism of control, with both meadow fescue and tall fescue naturally infected with loline-producing endophytes showing a resistance to Rhopalosiphum padi. We screened Elymus spp. naturally infected with endophytes that produced loline alkaloids at concentrations known to affect aphids on fescue but found no effect on these insects infesting Elymus. A synthetic loline-producing endophyte association with rye also had no effect on the aphids. After hypothesizing that the lolines were being translocated in the xylem in Elymus and rye rather than the phloem, we tested the rye and meadow fescue infected with loline-producing endophytes against a xylem feeding spittlebug. The endophyte in rye inhibited the feeding of the insect and reduced its survival, whereas the endophyte-infected meadow fescue had no effect on the spittlebug but reduced the number of aphids. Lolines applied to the potting medium of endophyte-free and endophyte-infected rye, ryegrass, and tall fescue resulted in a decrease in the aphid populations on the endophyte-free pasture grasses relative to the untreated controls but had no effect on aphid numbers on the rye. We tentatively conclude that lolines, produced in both natural and synthetic association with Elymus and rye, are partitioned in the xylem rather than the phloem, where they are inaccessible to aphids. [ABSTRACT FROM AUTHOR]

Under warmer and drier future conditions, global livestock and dairy production are threatened by impacts on the productivity and nutritional quality of pastures. However, morphological and nutritional adjustments within plants in response to warming and drought vary among species and less is known how these relate to production and forage quality. To investigate this, we grew two common pasture species, tall fescue (Festuca arundinacea: grass) and lucerne (Medicago sativa: legume), in a climate‐controlled facility, under different temperatures (ambient and elevated) and watering regimes (well‐watered and droughted). We found that drought had a strong negative impact on biomass production, morphology and nutritional quality while warming only significantly affected both species when response metrics were considered in concert, although to a lesser degree than the drought. Furthermore, interactions between warming and drought were only seen for lucerne, with a reduction in biomass and an increase in dead material and dry matter. In tall fescue, drought had bigger impacts on nutritional composition than morphological traits, while in lucerne, drought affected all morphological traits and most of the nutritional parameters. These findings suggest that in future climate scenarios, drought may be a stronger driver of changes in the morphology and nutritional composition of pasture grasses and legumes, compared to modest levels of warming. [ABSTRACT FROM AUTHOR]

Across much of the eastern United States, tall fescue [TF; Schedonorus arundinaceus (Schreb.) Dumort.], a cool‐season (i.e., C3) perennial grass, is the primary forage for pasture systems, thereby leaving producers vulnerable to reduced summer forage production and drought. Warm‐season (i.e., C4) forages can complement existing production systems by supplementing summer forage production and drought resiliency. Therefore, our objective was to compare five, C4 forage options in a grazing trial: switchgrass (SW; Panicum virgatum L.), eastern gamagrass (EG; Tripsacum dactyloides L.), a big bluestem (Andropogon gerardii Vitman) and indiangrass (Sorghastrum nutans L. Nash) blend (BBI), bermudagrass (BG; Cynodon dactylon L. Pers), and crabgrass (CG; Digitaria sanguinalis L. Scop.). Research was conducted 2014–2016 at two locations in Tennessee. Weaned beef heifers (237–242 kg initial weight) grazed 1.2‐ha pastures with three replications per species and location. Average daily gains (kg d−1) (0.62 [BBI], 0.41 [BG], 0.44 [CG], 0.42 [EG], 0.51 [SW]), grazing days (d ha−1) (412 [BBI], 459 [BG], 455 [CG], 664 [EG], 617 [SW]), and total gain (kg ha−1) (259 [BBI], 186 [BG], 200 [CG], 276 [EG], 315 [SW]) all varied among forages (P <.001). Similarly, forage nutritive values differed (P <.001) among forages: season‐long crude protein ranged from 94 (BG) to 115 (CG and EG) g kg−1, neutral detergent fiber (NDF), 601 (CG)–680 (SW) g kg−1, and acid detergent fiber (ADF) 379 (BG)–417 (EG) g kg−1. These forage options should be evaluated in the context of TF pastures to establish a broader understanding of their contribution within an overall forage system. Core Ideas: The C4 grasses provide a beneficial complement to C3‐dominated pasture systems.Native grasses tended to have greater rates of gain and grazing days than bermudagrass or crabgrass.Overall, rates of gain for the forages in this study were lower than in comparable studies.Native grasses had greater total gain per hectare than bermudagrass or crabgrass.Bermudagrass and crabgrass provided more grazing days during late summer than native grasses. [ABSTRACT FROM AUTHOR]

Simple Summary: This 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. [ABSTRACT FROM AUTHOR]

Waterlogging tolerance of eight C4 and seven C3 perennial forage grasses was reviewed. The median waterlogging duration was similar between species' type, ranging between 18 and 21 days. Inter- and intra-species variability was found in shoot and root biomass in response to waterlogging. Urochloa brizantha (C4), Brachiaria hybrid (C4) and Dactylis glomerata (C3) were the less tolerant species to waterlogging (shoot biomass median of 45%, 53% and 80% of controls), while U. humidicola (C4), Paspalum dilatatum (C4), Festuca arundinacea (C3) and Lolium perenne (C3) were the most tolerant (shoot biomass median of 97%, 101%, 87% and 94% of controls). A similar ranking of responses was found among species for root biomass. The formation of aerenchyma/root porosity (a key trait for waterlogging tolerance) was evaluated mainly in U. humidicola and P. dilatatum (C4 waterlogging-tolerant species), which showed considerable constitutive porosity (13% and 32%) and final values of 30% and 41% under waterlogging. Net photosynthesis and stomatal conductance as typical leaf physiological responses matched species' waterlogging tolerance, with the impact of hypoxia higher in C3 than in C4 species. Gaps in knowledge about waterlogging tolerance in forage grasses are: (i) additional studies on C3 perennial grasses for temperate pasture areas prone to waterlogging, (ii) identification of traits and responses aiding plant recovery after waterlogging (and also during the stress), (iii) reassessment of waterlogging tolerance considering plant developmental stage (e.g. adult vs young plants), and (iv) evaluation of sequential (i.e. waterlogging − drought) and combined (i.e. waterlogging + salinity) stresses, which often co-occur in pasture lands. The frequency and magnitude of floods are increasing in many pasture lands. In this context, this review aimed to quantitatively summarise all available information in the international literature related to waterlogging tolerance of perennial C4 and C3 forage grasses in worldwide use. This review reveals gaps in knowledge to guide future research aimed at improving forage production in areas prone to flooding. [ABSTRACT FROM AUTHOR]

Carbon allocation determines plant growth, fitness and reproductive success. However, climate warming and drought impacts on carbon allocation patterns in grasses are not well known, particularly following grazing or clipping. A widespread C3 pasture grass, Festuca arundinacea, was grown at 26 and 30°C in controlled environment chambers and subjected to drought (65% reduction relative to well‐watered controls). Leaf, root and whole‐plant carbon fluxes were measured and linked to growth before and after clipping. Both drought and warming reduced gross primary production and plant biomass. Drought reduced net leaf photosynthesis but increased the leaf respiratory fraction of assimilated carbon. Warming increased root respiration but did not affect either net leaf photosynthesis or leaf respiration. There was no evidence of thermal acclimation. Moreover, root respiratory carbon loss was amplified in the combined drought and warming treatment and, in addition to a negative carbon balance aboveground, explained an enhanced reduction in plant biomass. Plant regrowth following clipping was strongly suppressed by drought, reflecting increased tiller mortality and exacerbated respiratory carbon loss. These findings emphasize the importance of considering carbon allocation patterns in response to grazing or clipping and interactions with climatic factors for sustainable pasture production in a future climate. Summary Statement: Drought and warming differentially affect carbon partitioning above and belowground in a pasture grass, Festuca arundinacea, and reduce biomass and productivity. Combined drought and warming treatments amplify carbon loss. Clipping during climate extremes, particularly drought, reduces regrowth. [ABSTRACT FROM AUTHOR]

The potential of tall fescue (Schedonorus arundinaceus Dumort) and orchardgrass (Dactylis glomerata L.) as stockpiled forages has been documented; however, limited information describes the characteristics of other species, especially complex mixtures of cool‐season naturalized pastures. A 3‐yr study assessed the herbage mass, forage quality, and botanical composition of mixed cool‐season naturalized pastures [orchardgrass, tall fescue, clover (Trifolium spp.), narrowleaf plantain (Plantago lanceolata L.), and quackgrass (Elymus repens [L.] Gould)] in response to two stocking rates based on daily herbage allowances of 3.5% (low) or 7.0% (high) of heifer bodyweight. The stocking rate for the entire pasture area, including unoccupied paddocks during the grazing period, was 2.4 and 1.3 heifers acre−1 for the low and high treatments, respectively. Stockpiling began in August; grazing began in early November. The initial herbage mass and botanical composition were determined at the end of the stockpiling period. Herbage samples were taken throughout the fall grazing period at intervals of 11 to 19 d. The stocking rate had no effect on changes in botanical composition. Total legume percentage increased from 6% in Year 1 to 31% in Year 3 (P <.05). Herbage mass declined more quickly in Year 3 than in Years 1 and 2 (P <.05), probably because of the high percentage of legumes. As fall grazing progressed, crude protein content and in vitro true dry matter digestibility declined, and neutral detergent fiber content increased. Mixed cool‐season naturalized pastures could be used for stockpiling and grazed intensively without detrimental effects on subsequent stockpiling periods. Core Ideas: Stocking rate did not affect botanical composition, herbage mass, or forage quality.Intensive fall grazing did not affect the herbage mass quality of later stockpiling.The proportion of clover increased across 3 yr of fall grazing regardless of the stocking rate. [ABSTRACT FROM AUTHOR]

In forage-based beef cattle systems, bermudagrass [Cynodon dactylon (L.) Pers.] and tall fescue (Festuca arundinacea Schreb.) stand as widely used forage species. The strategic supplementation of animals may reduce forage intake, thereby potentially affecting the agronomic performance of these grasses. Our objective was to evaluate the impact of beef cattle supplemental feeding on forage accumulation, forage mass, and nutritive value in tall fescue and bermudagrass pastures. Two studies were conducted where pregnant beef cows were supplemental fed 1% of BW on DM basis of corn silage daily (SUP) or received no supplemental feeding (free-choice mineral; NON). Trial 1: conducted on bermudagrass pastures (BERM) grazed from late May to early October. Experimental design for BERM was completely randomized design with 4 pastures per treatment (n = 3 cows/pasture; average 5 years of age; 550 ± 72 kg initial BW). Trial 2: conducted on fescue pastures (FES) with an experimental design of a 2 x 2 factorial arrangement. The two factors evaluated were fescue type [TOXIC (507 ppm ± 0.82 SEM ergot alkaloids; 92.5% endophyte infection)] or non-toxin-producing (NT; 5 ppm ± 2.50 SEM ergot alkaloids; 38.6% endophyte infection) and two levels of supplemental feeding (NON or SUP). There were 3 or 4 replications per fescue x supplemental feeding treatment (n = 15 pastures), stocked with 3 cows/pasture (average age 4.75 years; 558 ± 73 kg initial BW) and grazed from early May through November. Forage accumulation (FA) was estimated every 28 d using the paired-cage method (4 exclosure cages/pasture). On each exclusion period, the forage mass (FM) was estimated both inside and outside the cages through destructive sampling method and samples analyzed for forage quality. Pasture was experimental unit and repeated measures were included in analysis. Bermudagrass FM tended to be increased by 31% with SUP (P = 0.09; 774 kg/ ha greater). Forage accumulation tended (P = 0.07) to be affected by feeding method x month. There was greater FA in June for SUP; however, there was greater FA for NON in July. SUP pastures had greater ADF (1% more; P = 0.01) and reduced TDN (1.5%; P < 0.01) than NON. Forage mass tended to be 10% greater for TOXIC pastures (P = 0.09; 409 kg/ha more forage mass). Supplemental feeding on fescue did not impact FM (P = 0.74). Forage accumulation was not impacted by fescue type, feeding method, nor the interaction (P > 0.30). Cows generally do not consume as much toxic fescue, thus more forage is available in pastures and supplemental feeding did not alter forage parameters. However, on a warm-season grass that is growing while supplemental feeding, forage availability was increased and maybe useful as method to increase stocking rates or as mitigation tool during drought. [ABSTRACT FROM AUTHOR]

A two-year field experiment was conducted to address the effects of mixture composition and legume-grass seeding ratio on the biomass yield and nutritional quality of legume–grass mixtures. Alfalfa (Medicago sativa L.), white clover (Trifolium repens L.), red clover (Trifolium pratense L.), orchardgrass (Dactylis glomerata L.), perennial ryegrass (Lolium perenne L.), and tall fescue (Festuca arundinacea Schreb.) were selected as plant materials. A total of seven legume–grass mixtures (A1: white clover, orchardgrass, and tall fescue; A2: alfalfa, orchardgrass, and tall fescue; B1: alfalfa, white clover, orchardgrass, and tall fescue; B2: red clover, white clover, orchardgrass, and tall fescue; C1: alfalfa, white clover, orchardgrass, tall fescue, and perennial ryegrass; C2: red clover, white clover, orchardgrass, tall fescue, and perennial ryegrass; and D: alfalfa, red clover, white clover, orchardgrass, tall fescue, and perennial ryegrass) were sown in two legume-grass seeding ratios (L:G) of 4:6 and 5:5. The results showed that A2 produced a higher two-year average biomass yield (14.20 t/ha) in L:G of 4:6 than that of other mixtures. The grasses biomass yield proportion decreased while legume biomass yield proportion increased with prolonged establishment time. A2 showed a higher crude protein yield (2.5 t/ha) in L:G of 4:6. C2 and A1 showed lower neutral detergent fiber (4.6 t/ha) and acid detergent fiber (2.8 t/ha) yields in L:G 5:5, while diverse mixtures showed higher water-soluble carbohydrate yields. Overall, A2 showed a relative feed value of 146.50 in L:G of 4:6, indicating that it has not only produced the higher biomass yield but also had a better nutritional quality. [ABSTRACT FROM AUTHOR]

Context: The incidence of extreme heat events (prolonged temperatures above 35°C) is increasing in the northern Victorian dairying region in Australia. This increase is having a significant effect on the performance of perennial ryegrass, which has traditionally been the major perennial species in these pastures. Aim: During seven extreme heat events, forage sampling was conducted on commercial farms to evaluate the effects of high temperatures on the nutritive characteristics of perennial ryegrass, tall fescue and lucerne. Our hypothesis was that reductions in nutritive characteristics with an increasing external temperature would vary among species. Methods: Before, during and after heat events, replicated samples of the three forage species were collected and analysed for in vitro dry matter digestibility (IVDMD), neutral detergent fibre (NDF), acid detergent fibre (ADF), water soluble carbohydrates (WSC) and crude protein (CP). Several anti-nutritive compounds (alkaloids in perennial ryegrass, and saponins and coumestrols in lucerne) were also measured. Key results: None of the temperate forage species evaluated maintained nutritive quality under high temperatures. Linear mixed model (LMM) analyses showed that for each degree rise between 23°C and 40°C, IVDMD and WSC concentrations decreased by 0.2% while NDF and ADF concentrations increased by 0.2% and 0.15% respectively. Concentrations of the alkaloid, ergovaline, in the base of the perennial ryegrass tiller were close to, or above, the recommended threshold level for animal health and welfare in three of the six samples taken during heat events. Conclusions: These results suggest that extreme heat events have a detrimental effect on the nutritive characteristics of the evaluated forage species. Implications: Heat-induced decreases in nutritive characteristics will potentially have serious implications for milk production and farm productivity. Further research, undertaken under controlled conditions of temperature, humidity and plant growth stage, is recommended to determine the full effect of these extreme summer conditions on forage nutritive characteristics. The effects of extreme heat events on the nutritive characteristics of pastures were studied in three farms in northern Victoria, Australia. Nutritive quality decreased at high temperatures in all species, with implications for milk production. Further research is recommended. [ABSTRACT FROM AUTHOR]

Frost seeding is a low‐cost effective strategy to introduce legumes into existing perennial pastures; however, it has been deemed unreliable in the upper southeast USA. We evaluated frost seeding planting rate effects of clover (Trifolium spp.) during the year of establishment on productivity and nutritive value of clover‐tall fescue [Festuca arundinacea (Schreb.) Darbysh.] pastures. Ball (T. nigrescens Viv.), crimson (T. incarnatum L.), red (T. pratense L.), and white (T. repens L.) clover were frost seeded in the Piedmont and Coastal Plain for 3 yr (2017–2019). Planting rates were 0X, 0.5X, 1X, 1.5X, and 2X of the recommended rate (X) of 5.6, 13.5, 11.2, and 5.6 kg ha–1 for ball, crimson, red, and white clover, respectively. At Coastal Plain, clover accounted for ≤16%. At Piedmont, ball, crimson, red, and white clover accounted for up to 27, 48, 21, and 15%, respectively. Notwithstanding similar clover frequency early in the growing season at both locations, competition from tall fescue in a higher rainfall environment is attributed to the lower clover contribution at Coastal Plain. Increasing clover frost‐seeding rate resulted in greater crude protein (130–154 g kg–1) and total digestible nutrients (586–610 g kg–1) only at Piedmont. The results from this study support the practice of frost‐seeding ball, crimson, red, and white clover at planting rates of 5.6, 20.2, 11.2, and 5.6 kg ha–1, respectively, into tall fescue pastures in the Piedmont; however, minimal or no benefits of frost seeding clover were observed in the Coastal Plain. Core Ideas: Frost‐seeded clover increased diversity and nutritive value of tall fescue pastures at Piedmont.At Piedmont, ball, crimson, red, and white clover accounted for 13–48% of the forage.Minimal, or no benefits, of frost seeding clover were measured at Coastal Plain.At Coastal Plain, clover accounted for ≤16% of the total herbage harvested. [ABSTRACT FROM AUTHOR]

Tall fescue [Schedonorus arundinaceous (Schreb.) Dumort. nom. cons. Lolium arundinaceum (Schreb.) Darbysh.] is the dominant pasture grass across much of the southeast of the USA. The species is productive, but grows slowly in summer. Plants also harbor an endophytic fungus (Epichloe coenophiala), which produces alkaloids that are toxic to cattle. Adding summer-productive forages to fescue-based systems may benefit animal production by providing extra herbage and diluting fescue toxins. A three-year study was conducted in Virginia, USA to determine animal and vegetation responses when alfalfa (Medicago sativa) or Sericea lespedeza (Lespedeza cuneata (Dum. Cours.) G. Don) swards were established into tall fescue pastures. Average daily gain (ADG) of steers and seasonal herbage mass dynamics were monitored from 2016 to 2018. Forage and weed species composition measurements were collected to address a secondary objective that sericea might suppress weeds through allelopathy. Steer performance was acceptable (0.73 kg d−1 ADG), but interseeded legumes did not improve weight gain. Steers avoided sericea plants, and this resulted in greater herbage mass accumulation in summer compared with other treatments. Alfalfa was selectively grazed and cover decreased to almost zero by year 3, while sericea cover increased to over 82%. We found little evidence that sericea was allelopathic against weeds. Neither summer-productive legume species proved to be satisfactory in improving summer animal performance in this tall fescue-based grazing system. [ABSTRACT FROM AUTHOR]

Warm-season grasses (WSG) incorporated into traditional cool-season rotational grazing systems to increase summer yields are typically established in monoculture in separate pasture areas. Few studies have evaluated alternative interseeded establishment of WSG, despite potential benefits for improving biodiversity and land-use efficiency. The objective of this study was to determine the impact of establishment method (monoculture vs. interseeded) on crabgrass pasture forage yield, nutritive value, and preference under equine grazing. Three adult standardbred mares grazed two main plots on two consecutive days (8 hr/d) for three grazing events in 2019: Jul 28/29 (GRAZE 1), Aug 20/30 (GRAZE 2), Oct 1/2 (GRAZE 3). Each main plot contained four replicates of three treatments: mixed cool-season grass (CSG); Quick-N-Big crabgrass (CRB) [ Digitaria sanguinalis (L.) Scop.] interseeded into existing cool-season grass (INT), and CRB established as a monoculture (MON). The cool-season grass mix included Inavale orchardgrass [ Dactylis glomerata (L.)], Tower tall fescue [ Lolium arundinaceum (Schreb.) Darbysh.], and Argyle Kentucky bluegrass [ Poa pratensis (L.)]. Herbage mass (HM) and sward height (SH) were measured prior to each grazing event and samples were collected (0800–1000 h) for chemical composition analysis. Observed grazing time (GT) in each sub-plot as determined by 5-min scan sampling was utilized as marker of horse preference. Forage HM was greater in MON (8043 ± 1220 kg/ha) than CSG (5001 ± 1308 kg/ha; P = 0.003), with a trend for greater total HM in MON vs. INT (6582 ± 1220 kg/ha: P = 0.06), but HM did not differ between INT and CSG. The SH was also greatest for MON (28 ± 1.11; INT: 23.6 ± 1.11; CSG: 19.7 ± 1.37 cm; P < 0.003). Forage nutrients (digestible energy and crude protein) were largely similar across treatments and met requirements of horses at maintenance. Horse GT was lower in MON (22.6 ± 3.77 min/sub-plot) than in INT (31.9 ± 3.79 min/sub-plot; P = 0.003) and there was a trend for lower GT in MON vs. CSG (29.9 ± 4.17 min/sub-plot: P = 0.07). These results indicate interseeding CRB would not effectively increase yields of traditional cool-season grass equine rotational grazing systems and would not supply similar levels of summer forage provided by monoculture establishment. Results of this study also suggest horses may prefer cool-season grass pasture forage over warm-season crabgrass. [ABSTRACT FROM AUTHOR]

BACKGROUND: Pasture farming in south‐western Australia is challenged by nutrient‐poor soils. We assessed the impact of microbial consortium inoculant (MI) and rock mineral fertiliser (MF) on growth, nutrient uptake, root morphology, rhizosphere carboxylate exudation and mycorrhizal colonisation in three pasture grasses – tall fescue (Festuca arundinacea L.), veldt grass (Ehrharta calycina Sm.) and tall wheatgrass (Thinopyrum ponticum L.) grown in low‐phosphorus (P) sandy soil in a glasshouse for 30 and 60 days after sowing (DAS). RESULTS: Veldt grass produced the highest specific root length and smallest average root diameter in both growth periods, and had similar shoot weight, root surface area and fine root length (except at 30 DAS) to tall fescue. Compared with the control, MI alone or combined with MF significantly increased shoot and root biomass (except root biomass at 30 DAS), likely due to the significant increases in root surface area and fine root length. Plants supplied with MI + MF had higher shoot N and P contents than those in the MI and the control treatments at 60 DAS. Malate, citrate and trans‐aconitate were the major rhizosphere carboxylates exuded at both 30 and 60 DAS. Malate exudation varied among species and treatments in both growth periods, but citrate exudation was consistently higher in the low‐P treatments (control and MI) than the MF and MI + MF treatments. CONCLUSION: Microbial consortium inoculant can positively influence pasture production in low‐P soil by increasing root surface area and fine root length, whereas exudation of nutrient‐mobilising carboxylates (citrate) is dependent more on soil P supply than microbial consortium inoculant. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

A less‐explored alternative to animal production in the subtropics is a mixture of perennial cool‐ and warm‐season forage grasses. This study aimed to determine a grazing management strategy to enhance forage production and attenuate the seasonality of a mixed pasture composed of kikuyugrass (Pennisetum clandestinum) and tall fescue (Festuca arundinacea). Four treatments were implemented in a completely randomized block design using a factorial scheme (2 × 2) with three replicates. The factorial arrangement consisted of two canopy heights (12 and 17 cm) associated with or without a single autumn grazing of 7 cm. Evaluations were conducted over 2 years. Nitrogen fertilization was performed only during the winter and spring seasons. Regardless of grazing height targets (12 or 17 cm), severe defoliation in autumn increased forage accumulation by 10% in mixed pastures composed of kikuyugrass and tall fescue; however, such management strategy should not be recommended because it delayed canopy recovery by 90–120 days, restrained winter grazing, and, paradoxically, increased forage production seasonality. Tall fescue was the dominant species in all treatments in the second year of evaluation, and we hypothesized that the lack of N fertilization during the summer impaired the persistence of kikuyugrass and was the main reason for this dominance effect. Therefore, we suggest evaluating summer N fertilization strategies, which could benefit both species and ensure the persistence of kikuyugrass in the mixture. [ABSTRACT FROM AUTHOR]

Low selenium (Se) in soil and forage can adversely affect on the quality of animalderived foods, and hence on human health. Lambs grazed on mixed pastures of alfalfa (Medicago sativa) and tall fescue (Festuca arundinacea) were supplemented with five levels of Se [0, 3, 6, 9 and 12 µg/kg body weight (BW)]. The intake of dry matter (DM) and organic matter (OM) varied with the level of Se supplementation, with a peak at 6 µg Se per kg BW (p = 0.05). Gross energy (GE) intake, digestive energy (DE) intake and metabolic energy (ME) intake were higher at 6 µg Se per kg BW than at other Se levels (p < 0.01); in addition, methane energy (CH4-E) output was lower at 6 µg Se per kg BW. Supplementation with Se significantly increased nitrogen (N) intake, faecal N and urine N, for which the peak values were 20.2 g N/, 5.62 g N/day and 7.92 g N/day, respectively, at 6 µg Se per kg BW. Se intake, blood Se, faecal Se, urine Se and retained Se were negatively correlated with forage crude protein (CP) content (p < 0.001) but were positively correlated with the content of neutral detergent fibre (NDF) (p < 0.001) and acid detergent fibre (ADF) (p < 0.001). Thus, we recommend the addition of 6 µg Se per kg BW to sheep grazed on pastures in regions with low soil Se. [ABSTRACT FROM AUTHOR]

A large gap between actual and potential herbage production of tall fescue is a major limitation for livestock production systems in Argentina. The objectives of this work were to (a) calibrate and test the ability of a published pasture–soil water model to represent herbage growth dynamics of tall fescue [Lolium arundinaceum (Schreb.) Darbysh.] under different growing conditions, using data from controlled field experiments; (a) use the evaluated model to predict the magnitude and time of the year that N or soil water would constrain tall fescue from attaining its potential growth rate in the south‐eastern Pampas of Argentina; and (c) quantify herbage production gains and temporal variability for a proposed improved management practice (IMP) of N fertilizer under different meteorological and soils scenarios. After tall fescue‐specific calibration, the model accurately represented the response of tall fescue herbage mass to irrigation and N fertilization (root mean square error of prediction <550 kg DM ha−1, R2 >.70) observed in thirteen single‐season, controlled, field experiments. Results from a 40‐year simulation show that the gap between fertilized and unfertilized tall fescue pastures in Argentina can exceed 14 t DM ha−1 year−1. The proposed IMP maximized responses to N in autumn and early spring, reducing the annual herbage production gaps by 38%. The effect of IMP on annual herbage production was larger (4–5 t DM ha−1 year−1) than the effect due to variability in soils' ability to store water (2–4 t DM ha−1 year−1) or annual variability in meteorological conditions (±1–2 t DM ha−1 year−1). This work provides a sound modelling approach to identify, for a particular forage species and site, most of the main gaps of herbage production; and to quantify, without the need of long‐term, expensive field studies, some of the potential gains (and risks associated with temporal variability), that could be achieved by producers. In addition, our results clearly indicate that site‐specific calibration is required for the model to provide accurate predictions and sound management advice to farmers. [ABSTRACT FROM AUTHOR]

Interseeding annual warm‐season grasses into pastures often increases forage accumulation. Yet, impacts on nutritive value and yields remain unreported. We analyzed forage collected from five Nebraska and Kansas experiments in 2015–2016 (eight environments) for crude protein (CP), neutral detergent fiber (NDF), and in vitro organic matter digestibility (IVOMD) concentrations and yields. Each experiment subjected perennial cool‐season grasses to two harvest frequencies (once at 90 d and twice at 45 and 90 d after interseeding) and four interseeded annual warm‐season grass types–pearl millet [Pennisetum glaucum (L.) R. Br.], sudangrass [Sorghum bicolor (L.) Moench ssp. drummondii (Nees ex Steud) de Wet & Harlan], a sorghum–sudangrass hybrid (S. bicolor × S. bicolor var. sudanense), and an unseeded control. Across environments, 90‐d CP and IVOMD concentrations increased while CP and IVOMD yields decreased in interseeded pastures when harvested twice, indicating presence of nutritive value‐yield tradeoffs. Pastures interseeded with sorghum–sudangrass had greater 90‐d IVOMD concentrations and CP and IVOMD yields when harvested once but only greater 90‐d IVOMD concentrations when harvested twice compared to unseeded pastures. Interseeding sorghum–sudangrass provided an effective strategy to increase CP and IVOMD yields in late summer in humid environments with tall fescue [Schedonorus arundinaceus (Schreb.) Dumort., nom. cons.] and in mid‐ and late summer in humid environments with smooth bromegrass (Bromus inermis Leyss.) and semiarid environments with western wheatgrass [Pascopyrum smithii (Rydb.) Á. Löve]. Interseeding annual warm‐season grasses did not consistently increase CP and IVOMD yields in semiarid environments with smooth bromegrass and crested wheatgrass [Agropyrum cristatum (L.) Gaertn.]. Core Ideas: Interseeding annual warm‐season grasses increases forage accumulation in pastures.Increased forage accumulation often comes with nutritive value tradeoffs.Harvesting interseeded pastures once increases late summer forage accumulation.Harvesting twice vs. once tends to increase nutritive value of interseeded pastures. [ABSTRACT FROM AUTHOR]

Bos grunniens (yak) are well-adapted to the rugged, high-altitude regions of central Asia where they are utilized for a variety of purposes. While the species is well-researched in its native land, limited research has been conducted in North America. The objective of this on-farm project was to evaluate performance of male and female growing yaks in pasture-based systems over two years. Grazing periods were 138 and 151 d for Yr 1 and Yr 2, respectively. The same plots were grazed both years, and pasture areas were approximately 0.49 ha each with three animals grazing each pasture in Yr 1 and two animals grazing each pasture in Yr 2. Pastures were comprised mostly of cool-season grasses with intermittent legumes and weeds. Yaks were assigned to one of four pastures based on sex with a total of six males (beginning weight 132.8 ± 13.5 kg) and six females (beginning weight 124.3 ± 34.4 kg) being grazed in Yr 1, and four males (beginning weight 157.3 ± 15.0 kg) and four females (beginning weight 160.9 ± 26.4 kg) being grazed in Yr 2. Animals in Yr 1 averaged 432 d of age, and animals in Yr 2 averaged 710 d of age at the start of the respective grazing periods. Pasture samples were collected throughout the study to assess nutritive value; botanical composition, presence of endophyte and concentration of ergovaline were also assessed. Tall fescue (Festuca arundinacea) samples collected at the end of the grazing period in Yr 2 averaged 32.65% infection and 146 ppb ergovaline. Data were analyzed using proc mixed procedure of SAS with sex and year as main effects and pasture as a random effect where α = 0.05. In Yr 1, males gained at a greater rate than females (0.45 kg/d vs. 0.23 kg/d; P = 0.0026). In Yr 2, a similar difference was observed for seasonal gains with males gaining 0.61 kg/d and females gaining 0.25 kg/d (P = 0.0003). A difference was also observed between growth rates of males in Yr 1 compared with males in Yr 2 (0.45 kg/d vs. 0.61 kg/d; P = 0.0024), but this difference was not observed in females. Gender can impact body weight gain in Bos grunniens raised in pasture-based systems with males gaining more rapidly than females. [ABSTRACT FROM AUTHOR]

Pasture legumes that persist under challenging agroecological conditions are crucial to ensure high lamb growth rates in dryland pastures. Pasture and lamb production from binary and diverse mixtures (Mix) of tall fescue (TF) with white clover (Whc), balansa clover (Bc), subterranean clover (Sc) and birdsfoot trefoil (Bft) were compared in a summer‐dry hill site in Corvallis, Oregon over a two‐year period. In 2018, all pasture combinations provided similar lamb liveweight gains (LWG, mean 177 g/day) in the first half of spring. Lambs in TF‐Bc and TF‐Mix pastures grew 31 to 41 g/day faster than those grazing TF‐Sc, TF‐Whc and TF‐Bft in the second half of spring (p <.05). Overall, TF‐Bc and TF‐Mix had higher (p <.05) legume contents (32% and 37% respectively) compared to other pasture combinations. In spring 2019, lambs that grazed the TF‐Mix and TF‐Whc pastures had higher LWG than those on other pastures (p <.05). The superior lamb growth rates were associated with the higher legume content and pasture quality maintained into the late spring period. Overall, the legume content of all pastures decreased over the course of the two‐year trial, with the decline being substantial for balansa clover. The present study confirmed that a high legume content of pastures leads to greater lamb growth rates. Total annual yields of pastures that had greater legume contents were superior to others (p <.05). Thus, a combination of self‐regenerating annual clovers with perennial legumes in pasture mixtures may ensure a higher legume content and longer persistence in dryland hill pastures. [ABSTRACT FROM AUTHOR]

Background: The low fertility of sandy soils in South‐Western Australia is challenging for the establishment of temperate perennial pastures. Aims: To assess whether microbial consortium inoculant may improve plant growth by increasing nutrient supply, root biomass and nutrient uptake capacity. Methods: Five temperate perennial pasture grasses–cocksfoot (Dactylis glomerata L. cv. Howlong), phalaris (Phalaris aquatica L. cv. Atlas PG), tall fescue (Festuca arundinacea L. cv. Prosper), tall wheatgrass (Thinopyrum ponticum L. cv. Dundas), and veldt grass (Ehrharta calycina Sm. cv. Mission) were tested in a controlled environment on the growth and nutrition with the microbial consortium inoculant and rock mineral fertiliser. Results: Veldt grass produced the highest shoot and root growth, while tall fescue yielded the lowest. Rock mineral fertiliser with or without microbial consortium inoculant significantly increased root and shoot biomass production across the grass species. The benefit of microbial consortium inoculation applied in conjunction with rock mineral fertiliser was significant regarding shoot N content in tall wheatgrass, cocksfoot and tall fescue. Shoot P and K concentrations also increased in the five grass species by microbial consortium inoculation combined with rock mineral fertiliser in comparison with the control treatment. Arbuscular mycorrhizal (AM) colonisation decreased with rock mineral fertilisation with or without microbial consortium inoculant except in cocksfoot. Conclusions: The response to microbial consortium inoculation, either alone or in combination with rock mineral fertiliser, was plant species‐dependent, indicating its potential use in pasture production. [ABSTRACT FROM AUTHOR]

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The study of factors influencing animal intake can provide a better understanding of the dynamics of the pasture ecosystem and serve as a basis for managing livestock in a more efficient way. We measured different sward surface heights of tall fescue in the process of short-term intake rate of sheep. There was a significant effect of sward surface height on herbage mass (P < 0.001), leaf lamina mass (P < 0.001), other species mass (P = 0.02), bite mass (P = 0.01) and short-term intake rate (P = 0.03) of sheep. There was a quadratic fit between time per bite and bite mass (P = 0.006). Multivariate analysis showed that the short-term intake rate and bite mass were positively correlated (r = 0.97), bite rate and total jaw movement rate were positively correlated but both were negatively correlated with time per bite. The sward surface height of tall fescue corresponding to the maximum short-term herbage intake rate was 22.3 cm. The underlying processes were driven by the bite mass, which was influenced by the leaf lamina bulk density and its consequences upon time per bite. This sward surface height can be adopted as a pre-grazing target for rotational stocking systems to optimize sheep nutrition on pastures. [ABSTRACT FROM AUTHOR]

Mob grazing, which uses very high stocking densities for short durations followed by a relatively long rest period, was designed to mimic bison (Bison bison) grazing in western U.S. grassland. This project assessed the suitability of mob grazing for livestock production in the Northeast. Objectives were to compare the effects of mob and rotational grazing on dry matter (DM) mass, nutritive value, and botanical composition across four grazing seasons. Eight, 0.10‐ha paddocks were established in 2014 as a randomized complete block with four replications, and seeded with alfalfa (Medicago sativa L.), white clover (Trifolium repens L.), orchardgrass (Dactylis glomerata L.), narrowleaf plantain (Plantago lanceolata L.), and tall fescue [Schedonorus arundinaceus (Schreb.) Dumort]. Mob‐grazed (MOB) paddocks were grazed by yearling beef cattle twice each year, (70–90–day interval), and rotationally grazed (ROT) paddocks were grazed four to six times each year (when sward height reached 25 cm). Cumulative pre‐grazing forage biomass (PGFM) of ROT was greater than MOB in three of four years. At the final grazing, the PGFM of ROT exceeded MOB by 2,500 kg ha−1. Within year, PGFM of ROT was more consistent, varying by only 1,000–1,400 kg DM ha−1 compared with 1,800–2,800 kg DM ha−1 for MOB. Grazing strategy altered botanical composition; ROT favored grasses while MOB favored alfalfa. Forage fiber content was consistently lower in ROT than MOB paddocks, indicating superior nutritive value. Results suggest rotational grazing is likely suitable for more consistent forage production of greater nutritive value in temperate, cool‐season grass‐legume pastures of the northeastern United States. [ABSTRACT FROM AUTHOR]

Field indicators of forage nutritive value could help farmers with rapid management decisions to optimize timing and intensity of grazing and meet objectives regarding animal nutrition. The objective of this research was to evaluate the likely relationships among leaf blade nutritive value, herbage mass and leaf stage of pasture regrowth under different growing seasons and residual sward heights. Experiments were performed on perennial ryegrass (Lolium perenne L.) and tall fescue (Festuca arundinacea Schreb.) pastures during spring and summer of 2016. In both pastures, three residual sward height treatments (3, 6 and 12 cm) were imposed on plots arranged in a split plot design, replicated in three blocks. Sward plots were harvested 5–6 times at intervals spaced 7–10 days apart to measure herbage mass, plant morphology, neutral detergent fibre (NDF), and the 24‐hr in vitro digestibility of NDF (NDFD) and dry matter (DMD) of leaf blades. Pastures showed strong (R2:.62 to.70), but variable, negative relationships between NDFD and herbage mass that varied with the rate at which pasture grew in each season of experimentation. Although there was a consistent NDFD decline as leaf stage of regrowth progressed (R2:.75 to.97), the NDFD also decreased as residual sward height increased, most notably in tall fescue. Additionally, findings indicate that the greater leaf length plasticity of tall fescue compared to residual sward heights may offer opportunities to manage both post‐ and pre‐grazing targets to achieve tall fescue forages with a similar high nutritive value as perennial ryegrass. However, the evaluation of this hypothesis at the farm level and its impacts on animal intake and performance warrants further careful investigations. [ABSTRACT FROM AUTHOR]

Epichloë fungal endophytes that systemically colonise cool-season grasses have become an internationally well-researched symbiosis. While sexual species of Epichloë can cause choke disease of grass seed heads, asexual forms are symptomless endophytes that colonise embryos to become seed transmitted. In mutualistic associations, the grass benefits through greater tolerance of abiotic and biotic stresses. In New Zealand, at least 12 species of naturalised and native grasses have been documented as infected with a range of asexual or sexual Epichloë. The impact of endophyte-infected ryegrass and tall fescue has been significant for pastoral farmers, with Epichloë enhancing pasture performance. Production of bioactive secondary metabolites reduces herbivory by invertebrate pests but some are also toxic to grazing animals. Selected strains of Epichloë have been utilised to reduce livestock problems while retaining improved pasture performance. Documented Epichloë-infected native grasses are rare, justifying greater efforts of discovery, description and conservation as taonga (a treasure) for Māori and all New Zealanders. Given their ecological success in New Zealand ecosystems, along with economic and environmental benefits, there are good prospects to further develop both endemic and naturalised Epichloë-grass associations that may benefit other cool-season grasses and potentially deliver new beneficial properties. [ABSTRACT FROM AUTHOR]

The effects of different management strategies on improving growth and modifying the botanical composition of C3 and C4 perennial grasses grown in a mixed canopy are underexplored. We aimed to evaluate the botanical composition and vegetation dynamics of a mixed canopy containing kikuyugrass (Pennisetum clandestinum Hochst. Ex Chiov) and tall fescue (Festuca arundinacea Schreber cv. Rizomat) subjected to four grazing management strategies over 22 mo. The experimental design was a randomized complete block in a factorial arrangement (two maintenance canopy heights: grazed to 7 cm in the autumn, or uninterrupted and maintained at 12 or 17 cm) with three replicates. The plots were sampled every month throughout the experimental period; the forage mass data were used to determine the botanical composition and leaf area index of the canopy. Although autumn grazing to 7‐cm height promoted an increase in pasture leaf proportion, it did not represent an effective augment in pasture leaf mass in the following winter–spring season. Canopies heights managed at 17 cm presented a greater proportion of tall fescue in herbage mass (81%) compared with those maintained at 12 cm (73%). Severe defoliation in the autumn delayed the regrowth to 12‐ or 17‐cm canopy heights by approximately 90–120 d in both evaluation years. From a farm‐level perspective, this result would restrict the recommendation of this grazing management strategy because this time lapse would demand that the pastures not be grazed for the 25–33% period of the year compared with the pastures that were not grazed in the autumn. [ABSTRACT FROM AUTHOR]

Two short-term dairy cow grazing experiments in mid-lactation (late spring) and late-lactation (late summer), were conducted in the Waikato region of New Zealand, to determine the effect of pasture species mixtures on urinary nitrogen (N) concentration and milk solids production. The mixtures included perennial ryegrass, tall fescue, lucerne and narrow-leaved plantain (cv. Tonic), structured to compare the two grass species, both with and without plantain. With plantain, apparent intake of plantain was 46%–70% of dry matter intake and estimated water intake was increased by 8%–21% over grass-lucerne swards. This led to significantly lower N concentrations of spot-sampled urine, by 38% in summer and 21% in spring, but no difference in milk production. A decline in apparent N intake was also implicated in summer. The effect of relatively high levels of plantain intake on reducing urinary N concentration is likely to be positive for reducing N leaching risk, particularly in late-lactation. [ABSTRACT FROM AUTHOR]

Tall fescue is the main perennial grass of the pastures of the temperate region of Argentina. However, after flowering in spring, tall fescue loses productivity and quality. Based on this, the objective of this work was to evaluate the effects of different post‐grazing mechanical cutting managements on the forage mass, leaf proportion, stocking rate, liveweight gain and liveweight production of tall fescue pastures. The treatments were post‐grazing mechanical cutting at anthesis (FC), post‐grazing mechanical cutting throughout spring and summer (SSC), and no post‐grazing mechanical cutting (NC). The experiment was performed from 2011 to 2014 in Argentina. The greatest and lowest forage mass were determined in September–November and May–September respectively. The leaf proportion of the SSC treatment was greater than that of the NC treatment, except in September–November. NC had higher stocking rate and lower liveweight gain than SSC, and neither NC nor SSC differed from FC. The liveweight production of the treatments was characterized by a trade‐off between stocking rate and liveweight gain. We conclude that FC is an attractive management because, with a single post‐grazing cutting, swards remain productive and leafy. [ABSTRACT FROM AUTHOR]

Mapping of the apparent soil electrical conductivity (ECa) can be used to estimate the variability of forage yield within a plot. However, forage production can vary according to the growing season and to soil properties that do not affect the ECa (e.g. nitrogen (N) content). The aim of this study was to assess the relationship between ECa and forage yield of tall fescue (Lolium arundinaceum (Schreb.) Darbysh.) during different regrowth periods and contrasting levels of N availability and then use this information to determine potential management zones. The ECa was measured and geo-referenced in a 5.75-ha paddock that sustained a permanent pasture dominated by tall fescue. In addition, a 30 m by 30 m grid cell size was chosen and 43 sampling areas, each 4 m2 in size, were geo-referenced and divided into two experimental units of 1 m by 2 m, one of which was fertilised with 250 kg N ha–1 (N250) at the beginning of four regrowth periods (spring 2015, spring 2016, autumn 2016 and autumn 2017) and the other was not fertilised with N (N0). At the end of each regrowth period, we estimated the accumulated biomass. During the spring growing season, accumulated biomass was positively associated with ECa in both N0 and N250 treatments (R 2 = 47% and 54%, respectively). By contrast, in autumn, accumulated biomass and ECa were poorly associated (R 2 = 10% and 27% for N0 and N250). This may be due to seasonal interactions that alter soil–yield relationships. To assess whether ECa can be used to determine management zones, the differences in accumulated biomass were compared through analysis of variance. Results showed that ECa is associated with the spatial distribution of tall fescue forage yield variability in spring at different N availabilities. Thus, ECa can be reliably used for defining management zones in marginal soils under permanent pastures. The present study has established that forage yield and response to nitrogen fertiliser are related to the soil apparent electrical conductivity (ECa). Therefore, ECa can be used to delimit environments with different productivities in temperate pastures. These results are the first step in developing algorithms for prediction of nutrient-application rates in environments of different potential at the paddock level. [ABSTRACT FROM AUTHOR]

The objective was to compare herbage mass (HM) estimates using a rising plate meter (RPM) and hand-sampled total collections using a forage ring. Accurate measurement of HM can be used to budget available forage in grazing systems, particularly as grass is a dynamic resource. While accurate estimation of HM can be achieved through total forage collection obtained from clipped quadrants, this is labor-intensive and time-consuming. For optimal and informed management, grass needs to be measured quickly and reliably in relation to both accuracy and precision. An RPM can be used to estimate the HM of grasslands based on the compressed sward height (CSH). However, device reliability can be affected by the naturally large variation of dry matter (DM) within CSH, which is governed by numerous factors, such as plant growth state, season species composition, and grassland management regime. Forage samples and heights were obtained weekly from grazed paddocks, which were rotated daily, over a 10-week period from June 6 to August 2, 2022. Paddocks were predominately endophyte-infected tall fescue. Each week two paddocks were randomly selected for sampling. Across both paddocks a total of 9 hand-clipped samples were randomly collected using a 0.25 m2 forage ring. All the forage within the forage ring was collected and dried for 48 h at 55 °C to determine forage DM. A Jenquip Manual Platemeter was used to measure the CSH within the forage ring before clipping. Herbage mass was estimated using the rising plate meter equation (kg DM/hectare = rising plate meter height × 158 + 200). The data were analyzed using CORR procedure of SAS 9.4. Herbage mass measured by total ring collection and RPM were not correlated (r = 0.15; P = 0.17). When RPM and total ring collection forage mass were averaged by pasture, they tended to be correlated (r = 0.44; P = 0.07). When the outlier weeks (samples 1, 5, 6, and 7) were removed, HM measured by the total ring collection was correlated (r = 0.41; P = 0.01) to RPM. The variability in correlations across pastures and time suggest that further work is needed to understand how variables like season, weather, and clipping procedures affect reliability of RPM to accurately predict forage mass. [ABSTRACT FROM AUTHOR]

The addition of perennial warm-season C4 grasses to perennial pastures, may contribute to carbon sequestration, in addition to increasing production and stabilising seasonal variations. We quantified root biomass in three pasture mixtures after 3 years of growth: a conventional mixture of Festuca arundinacea, Trifolium repens and Lotus corniculatus, the conventional mixture + Paspalum notatum and the conventional mixture + Paspalum dilatatum. Root biomass and content of carbon were higher at 0-10 cm than at 10-30 cm depth for both summer and winter sampling dates in all samples. Mixtures with Paspalum had higher root biomass than the conventional mixture in summer. No differences were observed between the two species of Paspalum in root biomass or carbon. These results show that the inclusion of Paspalum species in these systems may potentially increase carbon soil carbon, although further research is required to evaluate the effect of other management practices. [ABSTRACT FROM AUTHOR]

Tall fescue (Festuca arundinacea) is a Eurasian forage grass extensively planted in the United States. However, an endophytic fungus in tall fescue, Epichloë coenophiala, causes health problems in cattle. We predicted that cattle prefer to graze alternative forages when available. We also predicted that cattle use tall fescue more intensively in recently burned areas, as fire can increase forage quality. We tested these predictions in four diverse‐forage pastures in Iowa, comparing use by cattle of tall fescue and four alternative forages (non‐fescue cool‐season grasses, native warm‐season grasses, non‐leguminous forbs and legumes) to their availabilities at the pasture scale. We also examined how tall fescue influences the distribution of grazing at a fine scale (0.1‐m2 quadrats). Tall fescue was the most abundant forage (46% of plants), but composed only 26% of grazed vegetation. In contrast, legumes composed 12% of available forage but 25% of grazed vegetation. Other forages were used in proportion to availability. At a fine scale, total grazing frequency (proportion of plants grazed) was lower in quadrats containing abundant tall fescue, and higher in quadrats with abundant warm‐season grasses. Grazing frequency of tall fescue and other cool‐season grasses was greatest in recently burned quadrats, but total grazing frequency did not increase after burning. Our results show that although cattle graze tall fescue, particularly following burns, they limit their use of this grass. Given that tall fescue is underused, creates health risks for cattle, and degrades wildlife habitat quality, it may be advisable to reduce tall fescue in pastures. [ABSTRACT FROM AUTHOR]

Monitoring forage mass and nutritive value of pastures are encouraged to ensure adequate and efficient grazing management. For on‐farm monitoring, reliable instruments such as the rising plate meter (RPM) are useful and easy to achieve. The objective of this research was to verify the relationship between measurements of RPM (MRPM) to forage nutritive value based on seasonal and diurnal changes within a tall fescue sward under continuous stocking management. The study was conducted at the Plateau AgResearch and Education Center in Crossville, TN, from January 2015 to December 2016. The experiment was conducted in two 9‐hectare pastures consisting of a tall fescue [Schedonorus arundinaceus (Schreb.) Dumort., nom. cons., formerly Festuca arundinacea Schreb.] sward. During the 12‐month grazing period each year, total aboveground available forage was measured monthly in each pasture with a calibrated RPM. In addition, each month, several randomly placed 1‐m2 sample areas were collected at 7 a.m., 9 a.m., 12 p.m. and 4 p.m. to characterize forage nutritive value. Neutral detergent fiber, crude protein and in vitro total dry matter digestibility (IVTDMD) were predicted by means of near‐infrared spectroscopy. During the entire year of 2015, all correlation coefficients of forage nutritive value variables with MRPM were significant. However, in 2016, only IVTDMD showed a significant correlation with MRPM. Of the nutritive value variables, we chose to focus on the IVTDMD and MRPM relationship because it had one of the highest correlations for most seasons and different times of day, especially in 2015. There was a strong relationship between RPM measurements of herbage mass with IVTDMD, and this relationship is especially useful during the spring, where rapid growth is occurring. The same relationship was not found to be consistent during periods of slow forage growth, especially if recovering from a drought event. [ABSTRACT FROM AUTHOR]

Core Ideas: Broomsedge increases in low‐fertility tall fescue pastures.Phosphorus fertilization limits broomsedge increase in tall fescue pastures.Lime application limits broomsedge increase in tall fescue pastures.Applying recommended rates of lime and phosphorus increases tall fescue and limits broomsedge. Most Missouri tall fescue (Schedonorus arundinaceus (Schreb.) Dumort.) pastures grow on acidic, low‐phosphorus (P) soils. These conditions favor increases in broomsedge (Andropogon virginicus L.), a grass that is unpalatable for livestock. Three management strategies, 1) liming, 2) P fertilization, and 3) liming plus P fertilization, were evaluated for limiting broomsedge in tall fescue pastures. An established tall fescue pasture containing broomsedge was selected in southwest Missouri (soil pH 4.6, 6 lb/acre Bray I P). Lime was applied at 0x, 0.5x, 1x, and 2x the soil test recommendation (x = 3.67 ton/acre). Plots were treated with 0 or 50 lb P/acre. Plant counts for tall fescue and broomsedge were estimated over the next 3 years. Without P fertilization, broomsedge doubled over a 3‐year period. Phosphorus fertilization effectively maintained broomsedge at the initial level. The P treatment doubled the tall fescue count in 3 years following treatment, but without P, tall fescue counts remained at the initial level. Broomsedge increased nearly threefold without lime. Tall fescue more than doubled with the two highest lime treatments in 3 years. The 0x lime treatment resulted in no increase in tall fescue. Lime and P combined limited broomsedge increase to the greatest degree and produced the greatest increase in tall fescue. Increased vigor of tall fescue resulting from improved soil fertility likely influenced the increase in tall fescue and limited further encroachment of broomsedge. Applying lime and P could improve pastures by encouraging growth of desirable grasses and discouraging increases in common weeds like broomsedge. [ABSTRACT FROM AUTHOR]

Tall fescue (Festuca arundinacea (Schreb) Darbysh.) has the potential to become a useful component of irrigated dairy pastures in northern Victoria owing to its high dry matter (DM) production compared with perennial ryegrass. However, tall fescue is not widely grown because its grazing management is perceived as difficult. In October 2010, a tall fescue-white clover pasture was established and irrigated. In September 2011, six grazing-management treatments were imposed over 3 years, involving grazing: at 1-leaf stage; at 2-leaf stage (1.5-leaf stage during spring); at 3-leaf stage (2.5-leaf stage during spring); at intervals based upon days between grazings ranging from 15 days in October-December to 60 days in winter; at intervals as above except for 21 days in October-December; and at intervals approximating that of a well-managed perennial-ryegrass-based pasture. Measurements included pre- and post-grazing pasture mass, nutritive characteristics, botanical composition and plant frequency. Pasture consumption from the treatment grazed at the 3-leaf stage was >3.5 tDMha-1 year-1 (30%) greater than from the three most frequently grazed treatments. However, crude protein content was 1-3% DM units lower when grazed at the 3-leaf stage compared with the two most frequently grazed treatments. There was no effect on estimated metabolisable energy or neutral detergent fibre contents of the pasture on offer. Differences in pasture composition between the pastures grazed at the 3-leaf stage and those most frequently grazed emerged over time and were most conspicuous in the third year, with a greater plant frequency (79% v. 66%) and tall fescue content (61% v. 40% DM) and lower weed content (14% v. 28% DM). From the study, a grazing regime for tall fescue based on the 3-leaf stage appears promising because it produced the most DM over the experiment. A disadvantage of this regime was the need for an extra mowing each year. The practicality of this approach to grazing tall fescue needs to be tested at the whole-farm level. [ABSTRACT FROM AUTHOR]

Enhancing pasture persistence is crucial to achieve more sustainable grass-based animal production systems. Although it is known that persistence of perennial ryegrass is based on a high turnover of tillers during late spring and summer, little is known about other forage species, particularly in subtropical climates. To address this question, this study evaluated survival of grazed tall fescue tillers growing in a subtropical climate. We hypothesized that hard tactical grazing during winter to remove reproductive stems (designated as 'flowering control'), and nitrogen fertilization in spring, would both improve tiller survival over summer, and thus enhance tiller density. This was assessed in two experiments. In both experiments, few tillers appeared during late spring and summer and so tiller density depended on the dynamics of vegetative tillers present in the sward in spring. In Experiment 2, flowering control and nitrogen fertilization both enhanced the survival of that critical tiller cohort, but the effects were not additive. Responses were similar but not statistically significant in Experiment 1, which had a warmer, drier summer and lower overall survival rates. Unlike grasses in temperate environments, persistence of tall fescue in this subtropical site appeared to follow a 'vegetative pathway'; i.e., new tillers were produced largely in autumn, from vegetative tillers that survived the summer. [ABSTRACT FROM AUTHOR]

Diversifying farm activities can reduce the business risk of agricultural production. The aim of the present study was to investigate the effect of diversifying the types of dairy pastures sown on (1) the average seasonal growth rate (kg DM/ha/day) of pasture and (2) the variability of seasonal growth rate of pasture over time by diversifying the types of pastures grown on a dairy farm. This approach is similar to the approach used to assess the diversification of annual cropping activities, although repeated harvest of pasture by grazing animals and the seasonality of pasture DM production complicates the question. The question investigated was 'How does substituting chicory (Cichorium intybus L.) or tall fescue (Festuca arundinaceae Schreb.) monocultures for a perennial ryegrass (Lolium perenne L.)-white clover (Trifolium repens L.) pasture in increasing proportions affect (1) the average growth rate (kg DM/ha.day) of pasture and (2) the variability of growth rate of pasture in each season?'. The biophysical model DairyMod was used to simulate 30 years growth of a mixed sward of perennial ryegrass and white clover and monocultures of chicory and tall fescue for two rain-fed locations in the high-rainfall zone of southern Australia. Including chicory in the pasture base had the potential to increase pasture growth rate during the summer-early autumn period compared with growing perennial ryegrass-white clover alone. This increase in pasture growth rate increased variability, and reduced growth rates in late autumn-winter and spring. The simulated growth rates of tall fescue and perennial ryegrass were strongly correlated in all seasons; hence, tall fescue did not reduce the variability of total DM. Further analysis would include price correlations and variability and consider the whole-farm implications. The analysis presented here for the highrainfall zone showed that introducing alternative forages may have benefits in terms of increasing pasture growth rates at critical times of the production year, but the variability of the growth rate was not reduced. [ABSTRACT FROM AUTHOR]

Tall fescue [Lolium arundinaceum (Schreb.) Darbyish.] can be autumn stockpiled to extend the grazing season. The objectives of this study were to determine (i) optimum mid- August N fertilization rate for stockpiled yield with or without red clover (Trifolium pratense L.), (ii) if mid-August N applications affect the persistence of red clover in a mixed sward, (iii) how N fertilization rates affect total ergot alkaloids (TEA) in November, and (iv) if N fertilization rates and harvest months affect nutritive value through winter. At the University of Missouri Forage Systems Research Center near Linneus, MO, five N fertilization rates were applied in mid-August and forage was harvested the following November through March. Dry matter yield, crude protein (CP), and in vitro true digestibility (IVTD) were determined for each sampling date. Each November, TEA were measured from tall fescue-only plots. Red clover densities were determined each June. Stockpiled yields increased with increasing N fertilization rates up to 168 kg N ha-1. Red clover neither impaired nor improved stockpiled forage yield. Red clover densities decreased linearly as N fertilization rate increased the previous August. Sward type affected nutritive value minimally. Losses in CP and IVTD through winter averaged 20 and 60 g kg-1, respectively, over the 4 yr. Application of 56 kg N ha-1 provided forage with CP concentrations that would support nonlactating beef cows. Fertilization rates of ≥112 kg N ha-1 resulted in November TEA concentrations that are toxic to grazing livestock. For optimum stockpiled forage yields, forage should be fertilized with <112 kg N ha-1 and grazed before January. [ABSTRACT FROM AUTHOR]

This research evaluated the effects of supplementing extruded dried distillers' grains (DDG) cubes to grazing steers on subsequent finishing performance and carcass characteristics. Steers (n = 140) grazed tall fescue (Festuca arundinacea)/bermudagrass (Cynodon dactylon) pastures from 14 April to 17 September 2020 with supplementation treatments (n = 3 pastures/treatment) that included: 1) Fertilized Control (FC), no supplementation on N fertilized pastures (112 kg N/ha); 2) Fertilized Supplement (FS), supplemented DDG cubes at 2.9 kg/d prorated for 3-d/wk feeding on N fertilized pastures; and 3) Supplement (S), supplemented DDG cubes at 0.75% of BW/d prorated for 5-d/wk feeding on unfertilized pastures. All animals were followed through the finishing phase in a commercial feedyard to investigate carryover effects on feedlot performance in 2 pens comingled across supplemental treatment. Carcass characteristics were evaluated via ultrasonography on d0 and d84 of finishing, and measurements were obtained at harvest. Feed DMI were segregated to individual animals according to Guiroy et al. (2001) and Tedeschi and Fox (2020b). Supplemented animals were heavier (P < 0.01) at feedlot entry than FC, but harvest BW did not differ (P = 0.23). However, S and FS required 37 fewer days on feed (P = 0.01) than FC. Supplementation on pasture reduced total feed required (P = 0.02) and feed costs (P = 0.01) relative to FC. Gains were greater (P = 0.02) for FC and FS than S from d0 to d84, but did not differ thereafter (P = 0.15). At harvest, FC had the greatest dressing percent (P < 0.01) and lower yielding carcasses than FS (P = 0.01), but did not differ (P = 0.11) from S. Overall, extruded DDG cube supplementation during grazing did not negatively affect subsequent feedlot performance or carcass characteristics, but reduced the total feed required for finishing. [ABSTRACT FROM AUTHOR]

Treatment of toxic endophyte-infected tall fescue [Lolium arundinaceum (Schreb.) Darbysh] with metsulfuran-methyl {Methyl 2-[[[[(4-methoxyl-6- methyl-1,3,5-triazin-2-yl)-amino]carbonyl]amino] sulfonyl] benzoate}, as delivered by Chaparral herbicide (Dow AgroSciences, Indianapolis, IN) can mitigate fescue toxicosis and enhance forage nutritive value by suppressing seedhead emergence. A grazing experiment was conducted with steers (2013) and heifers (2014) to evaluate animal and plant responses to grazing management of mixed cool-season grass pastures treated with Chaparral. Continuous and rotational stocking treatments were assigned to six, 3.0-ha pastures in a randomized complete block design with three replications in 2013 and two replications in 2014. Each pasture had six tester animals, and stocking rates were varied using put-and-take animals. Pastures were grazed from 16 April to 8 July 2013 and 20 May to 12 Aug. 2014. Pasture carrying capacity was 20% greater for rotational than continuous stocking. Calves on rotationally stocked pastures also had 26% greater average daily gain (ADG) and body weight (BW) gain per hectare than those on the continuous treatment. Pre-grazed herbage had less neutral detergent fiber (NDF) and acid detergent fiber (ADF) than post-grazed herbage and herbage from continuously stocked pastures in 2013, but they did not differ in 2014. Crude protein (CP) was lower in post-graze rotational pasture than in continuous or pre-graze rotational pasture. Fescue roots in rotationally stocked pastures had greater water soluble carbohydrates (WSC) and N concentrations than continuously stocked pastures following the second year of grazing. Results indicated that rotational stocking of Chaparral treated mixed pastures can improve animal performance and pasture productivity. [ABSTRACT FROM AUTHOR]