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Variable results from studies of the associations between grazing management and soil microbiological properties in grasslands suggest the need for further investigation. We assessed the response of soil microbiological properties to conventional and adaptive multi‐paddock (AMP) grazing management practices at paired farms at five locations in the southeastern United States. We measured total DNA and abundances of fungi and bacteria by quantitative polymerase chain reaction (qPCR) as proxies for soil microbial biomass, potential carbon, nitrogen, and phosphorus cycling activities using qPCR of functional genes, and carbon mineralization activities by respiratory assays. Abundances of fungi (p = 0.009) and bacteria (p = 0.001) were greater under AMP management compared to conventional management; however, there was no difference in the fungal/bacterial ratios between management practices. Gene copies encoding for nitrification, denitrification, and phosphate hydrolysis were significantly greater (p < 0.05) under AMP compared to conventional management. Basal soil respiration was elevated (p = 0.004) under AMP compared to conventional management presumptively due to the greater abundance of microbes that were actively transforming plant exudates and residues. In contrast, labile carbon limitation of respiratory activities was greater (p ≤ 0.01) under conventional compared to AMP management indicating decreased processing of soil carbon and formation of microbial biomass. Using discriminant function analysis, the 19 biological response variables successfully classified 94% of the 180 soil samples according to grazing management. In summary, AMP grazing management influenced the numbers and key activities of soil microbes in a distinctive manner that is associated with the retention of soil organic carbon and nitrogen reported in these grazed grasslands. Core Ideas: Adaptive multi‐paddock grazing increased soil bacterial and fungal populations relative to conventional grazing.Adaptive multi‐paddock grazing increased indicators of carbon (C) and nutrient cycling relative to conventional grazing.Discriminant analysis using 19 soil biological variables classified 168 of 179 soil samples by grazing management.Soil microbial response to grazing management was associated with soil C and N retention reported at these sites. [ABSTRACT FROM AUTHOR]

Soils comprise the largest pool of terrestrial carbon yet have lost significant stocks due to human activity. Changes to land management in cropland and grazing systems present opportunities to sequester carbon in soils at large scales. Uncertainty in the magnitude of this potential impact is largely driven by the difficulties and costs associated with measuring near-surface (0–30 cm) soil carbon concentrations; a key component of soil carbon stock assessments. Many techniques exist to optimize sampling, yet few studies have compared these techniques at varying sample intensities. In this study, we performed ex-ante, high-intensity sampling for soil carbon concentrations at four farms in the eastern United States. We used post hoc Monte-Carlo bootstrapping to investigate the most efficient sampling approaches for soil carbon inventory: K-means stratification, Conditioned Latin Hypercube Sampling (cLHS), simple random, and regular grid. No two study sites displayed similar patterns across all sampling techniques, although cLHS and grid emerged as the most efficient sampling schemes across all sites and strata sizes. The number of strata chosen when using K-means stratification can have a significant impact on sample efficiency, and we caution future inventories from using small strata n, while avoiding even allocation of sample between strata. Our findings reinforce the need for adaptive sampling methodologies where initial site inventory can inform primary, robust inventory with site-specific sampling techniques. [ABSTRACT FROM AUTHOR]

Rhizomatous growth and associated physiological integration can allow a clonal dune species to potentially compensate for the selective removal of leaves associated with herbivory. Hydrocotyle bonariensis is a rhizomatous clonal plant species that is abundant in the coastal dune environments of the southeastern United States that are inhabited by large feral horse populations. H. bonariensis has been shown to integrate resources among ramets within extensive clones as an adaptation to resource heterogeneity in sandy soils. In this study, we hypothesized that clonal integration is a mechanism that promotes H. bonariensis persistence in these communities, despite high levels of herbivory by feral horses. In a field experiment, we used exclosures to test for herbivory in H. bonariensis over a four-month period. We found that feral horses utilized H. bonariensis as a food species, and that while grazing will suppress clonal biomass, H. bonariensis is able to maintain populations in a high grazing regime with and without competition present. We then conducted an experiment in which portions of H. bonariensis clones were clipped to simulate different levels of grazing. Half of the clones were severed to eliminate the possibility of integration. We found that after 12 weeks, the mean number of leaves and ramets increased as the grazing level increased, for integrated clones. Integrated clones had significantly increased biomass production compared to the severed equivalents. Our research suggests that rhizomatous growth and physiological integration are traits that allow clonal plant species to maintain populations and to tolerate grazing in coastal dune environments. [ABSTRACT FROM AUTHOR]

Can well-defined access rights to publicly owned land be as effective as privatization in increasing productivity and wealth? In this paper, I evaluate the impact of public property rights using the 1934 Taylor Grazing Act, which determined secure access rights for ranchers to newly created, large grazing districts in the Western United States. Using satellite-based vegetation data, I exploit spatial discontinuities across grazing district boundaries and find that public lands with well-defined access rights for ranchers are at least 10% more productive than lands without. Immediately after establishing grazing districts, ranchers inside these districts held more cattle, and reported higher income and farm values than their counterparts outside. Despite ranchers being unable to invest in publicly owned lands, these magnitudes are similar to outright privatization. Instead, I argue that secure access rights resolve uncertainty around future usage and align the incentives of ranchers and regulators, thus incentivizing sustainable and profitable usage. I provide two results supporting this hypothesis: Areas with stronger pre-reform state capacity show larger increases in vegetation; and, monthly patterns on vegetation are consistent with the adoption of productivity-increasing fallowing practices. I investigate alternative explanations, and find no empirical support for differential initial productivity, negative spillovers, or systematic local manipulation of boundaries. [ABSTRACT FROM AUTHOR]

For nearly a century, the federal government has authorized ranchers to graze livestock on large areas of federal lands in the western United States. Federal-land grazing has generated substantial conflict in recent decades, as conservation interests and others have lobbied and litigated against what they view as inappropriate and destructive use of federal lands. This has produced a predictable backlash among ranching interests, including efforts to roll back the regulations relied on by environmental litigants and aggressive confrontations with federal regulators. But such conflict is not inevitable. Competing demands on these lands can be resolved through voluntary means and positive incentives for conservation practices, as they often are on private lands. On public lands, however, federal law erects substantial barriers to this market approach by imposing use-it-or-lose-it rules on federal grazing permits. In this Article, we discuss those barriers and offer statutory and regulatory reforms that would overcome them while facilitating markets for conservation on federal grazing lands. [ABSTRACT FROM AUTHOR]

The incorporation of alfalfa (Medicago sativa L.) into bermudagrass [Cynodon dactylon (L.) Pers.] forage systems in the southern United States has increased. Stockpiling this mixture may extend the grazing season into the fall and winter months with high-quality forage. The objective of this 2-year study was to evaluate agronomic and structural responses of alfalfa–bermudagrass mixtures managed under five stockpiling periods (6, 8, 10, 12, or 14 weeks) in two locations (Shorter, AL, and Tifton, GA). Across locations, stockpiling mixtures for 8 weeks or longer (2400 lb DM ac−1, on average) resulted in greater (P = 0.001) herbage accumulation than 6 weeks (3185 lb DM ac−1). The alfalfa proportion was similar among stockpiling periods in Shorter but greater (P = 0.043) at 10 and 14 weeks than 6, 8, and 12 weeks in Tifton. A location × year × stockpiling interaction was observed for crude protein (CP, P < 0.001) and in vitro true dry matter digestibility over 48 h (IVTDMD48, P < 0.001). Crude protein concentrations were similar among stockpiling periods in 2020 in both locations. In 2019, however, CP concentrations reduced with increasing stockpiling period length in Shorter and were similar among treatments in Tifton, except for the lesser CP at 8 than at 10, 12, and 14, weeks. Forage IVTDMD48 concentrations declined with increasing stockpiling period length at both locations, with a more pronounced decline in Shorter in 2019. Results suggest that stockpiling alfalfa– bermudagrass mixtures for up to 8 weeks is a viable option to supply high nutritive value forage and lower lodging losses into the early winter months. [ABSTRACT FROM AUTHOR]

Organic, grassfed (OGF) dairy, which requires higher pasture and forage dry matter intake compared with standard organic dairy practices, is unique both in its management needs and in production challenges. The OGF dairy sector is rapidly growing, with the expansion of this industry outpacing other dairy sectors. There is a lack of research outlining OGF dairy production practices, producer-identified research needs or social factors that affect OGF systems. The objectives of this study were to, with a group of OGF dairy producers, (1) assess information regarding current production practices and producer knowledge, and (2) identify agronomic and social factors that may influence milk production on OGF farms across the United States. A mail survey, focused on demographics, forage and animal management, knowledge, and satisfaction of their farm, was developed and distributed in 2019, with 167 responses (47% response rate). The majority of producers indicated they belonged to the plain, or Amish-Mennonite, community. Milk production was greater on farms that had Holstein cattle, as compared to farms with Jerseys and mixed breeds, and employed intensive pasture rotation. Furthermore, most producers reported the use of supplements such as molasses and kelp meal, which can improve milk production, but also increase feed costs. Producers who indicated that they were at least satisfied with their milk production also reported high levels of knowledge of grazing management and cow reproductive performance. Comparison of response data from plain/non-plain respondents revealed that those that did not identify as plain were more likely to utilize certain government programs, had different priorities and utilized technology more frequently. Based on these results, more research exploring financial and production benchmarks, effective communication strategies to reach OGF producers and methods to improve cattle production through improved forage quality is needed. [ABSTRACT FROM AUTHOR]

Within managed ecosystems, such as some livestock grazed grasslands, soil physical, chemical, and biological properties may be severely compromised relative to native grasslands. Conventional grazing (CG) management, commonly referred to as continuous grazing, can affect soil properties and health by reducing soil C stocks and other available nutrients, while creating bare patches in vegetation that may enhance erosion and runoff. In contrast, adaptive multipaddock (AMP) grazing, an intensive form of rotational grazing that moves dense cattle herds quickly over the land followed by rest periods for the regrowth of plants, has been proposed as a regenerative grassland management tool that can improve soil properties such as soil C stocks, soil structure, as well as nutrient and water retention. Our research analyzed soils from 10 grasslands in the southeast United States representing either CG or AMP grazing management. We analyzed the A‐horizons of these soils for physical, chemical, and biological properties considered indicators of soil health across each management type. Chemical soil properties (e.g., cation exchange capacity [CEC], base saturation [BS], electrical conductivity [EC]) were improved where AMP grazing management was implemented. Additionally, farms using AMP grazing management had greater A‐horizon C and N stocks in bulk soils and across multiple soil organic matter (SOM) fractions. No biological indicators measured were affected by the grassland management except potential N mineralization rate, which was lower under AMP. Taken together, these results provide evidence that AMP grazing management could be implemented to regenerate several grassland soil properties across land currently under conventional grazing management. Core Ideas: We found improved chemical soil health indicators where AMP grazing was implemented.Greater AMP A‐horizon C and N stocks were apparent across multiple SOM fractions.Biological soil health indicators were largely unaffected by grazing management.Results show that AMP grazing could be used to regenerate grassland soil health. [ABSTRACT FROM AUTHOR]

Variability of protein and energy supply from pasture during the grazing season is a primary factor that can influence milk production of grazing organic dairy herds in the Northeast United States. This study evaluated the effects of altering the crude protein (CP) content of dietary supplements included in dairy rations fed to grazing organic dairy herds, on milk production and composition. Six commercial organic farms participated in a 6-wk trial, consisting of a 2-wk baseline period and 4-wk experimental period. Farms were paired by their summer 2017 milk urea nitrogen profile, and farms within each pair were assigned by restricted randomization to (1) continuation of their regular supplements (n = 3, control group, CON), or (2) supplement with altered CP as percentage of dry matter, formulated using an organic barley and roasted soybean mix (n = 3, treatment group, TRT). Throughout the 6-wk trial, individual milk samples were collected at 2 consecutive milkings weekly, while pasture and supplement samples, pasture measurements, and management information were collected twice weekly per farm. Data were statistically analyzed using the MIXED procedure of SAS (version 9.4, SAS Institute Inc.) for all parameters, and effects of treatment, week, and their interaction (treatment × week) were determined. The supplement CP (percentage of dry matter) during the baseline period was 13.5% for CON and 15.3% for TRT and 14.8% for CON and 19.3% for TRT during the experimental period. Milk production was 21% higher during the experimental period for TRT compared with CON (24.1 vs. 19.9 kg of milk per day, respectively). Milk production decreased for CON from wk 1 to wk 6 (23.6 vs. 20.4 kg of milk per day), whereas TRT maintained milked production from wk 1 to wk 6 (22.8 vs. 22.7 kg of milk per day). Milk composition was different between groups, with CON having higher fat percent (4.21 vs. 3.73%, respectively) and protein percent (3.15 vs. 3.05%, respectively) compared with TRT for the 6 wk. The milk urea nitrogen concentrations were similar between TRT and CON for the baseline period (11.9 vs. 12.1 mg/dL) and the final week of the experimental period (14.5 vs. 14.2 mg/dL). Although the effects of different diet CP fractions, particularly rumen undegradable protein and soluble protein, must be further delineated, these results indicate that altering the CP content of dietary supplements fed to grazing organic dairy cattle during the summer period in the Northeast US could be a useful mechanism to maintain milk production. [ABSTRACT FROM AUTHOR]

Background: The duration and frequency of eating occasions has been identified as a factor contributing to poor dietary quality among U.S. adults. The objective of this study is to examine whether grazing, defined as eating more than three times a day, affects total daily caloric intake and dietary quality measured by the 2015 Healthy Eating Index (HEI-2015). Methods: We used a multivariate individual fixed-effects model to compare the caloric intake and dietary quality of individuals who grazed on 1 day but not another. This allowed us to control for differences in individual food intake and diet quality preferences among study participants. We use the National Health and Nutrition Examination Survey (NHANES), 2007-2018, and include data for adults aged 18 years or older who reported 2 days of dietary intake and were not pregnant or lactating (n = 27,775). Results: Grazing increased total daily caloric intake by 205 cal and increased the daily HEI score by 0.59 points. Grazing increased HEI component scores for total fruit, whole fruit, and refined grains, and decreased HEI component scores for saturated fats. Morning grazing increased total daily caloric intake by 159 cal and increased the daily HEI score by 0.87 points — primarily by increasing component scores for total fruit, whole fruit, whole grains, total dairy, seafood and plant proteins, and sodium. Evening grazing increased daily caloric intake by 76 cal and decreased the daily HEI score by 0.41 points — primarily by decreasing the component scores for total fruit, whole grains, fatty acids, and saturated fats. Evening grazing increased HEI component scores for sodium and refined grains. Conclusions: Grazing increases daily caloric intake and can decrease dietary quality (particularly when grazing in the evening). [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the effects of pasture (cocksfoot cv. porto (CFP) and lucerne) and supplementation of grazing lambs with pellets with or without plant oil infusion on performance and carcass characteristics. Forty-eight White Suffolk x Corriedale first-cross weaners were randomly assigned to one of four treatments in a split-plot experimental design: (1) CFP or lucerne pastures only (control); CFP or lucerne pastures supplemented with pellets infused with oil from (2) canola (CO); (3) rice bran (RBO) and (4) no oil pellets (NOP). Lucerne and CFP pastures were considered as the main plot effect, and played the role of basal pastures. Lambs grazing lucerne or CFP pastures with pellet supplementation achieved carcass weights of >22 kg at 9 weeks, which met the specific requirements of Asian and United States of America export markets. Pellet supplementation did not affect final liveweight, average daily gain, body length, withers height and chest girth of grazing lambs. Dressing percentage of lambs grazing CFP pasture with pellet supplementation and lambs grazing lucerne pasture with RBO supplementation increased compared with lambs on pasture grazing only. Although supplementing lambs on CFP pasture with CO had relatively negligible impact on feed conversion efficiency, it significantly increased over the hook trade value compared with lambs grazing CFP pasture only. In conclusion, lucerne or CFP pasture plus pellet supplementation produced lamb carcasses >22 kg suitable for the export market. CO had relatively low feed cost per unit daily gain (0.9 $AU/kg on CFP pasture and 0.6 $AU/kg on lucerne pasture) and could also be used as a tactical supplementation tool for increasing the carcass weight of lambs grazing CFP pasture. [ABSTRACT FROM AUTHOR]

Fescue toxicosis poses a significant challenge to the United States beef industry, resulting in considerable economic losses. This syndrome arises from the consumption of tall fescue (Schedonorus arundinaceous) infected with the wild-type endophyte (WE; Epichloe coenophiala), which produces toxic alkaloids. The most effective solution for mitigating fescue toxicosis is renovating WE tall fescue pastures to novel endophyte-infected (NE) tall fescue. However, pasture renovation is costly and may not be feasible under certain conditions, with the economic profitability taking up to 3 yr. While the potential of condensed tannins (CTs) in specific leguminous forages to reduce the absorption of toxic alkaloids is recognized, their use as supplements remains underexplored. This study aims were to investigate the potential of CT-containing feed supplements, specifically sericea lespedeza (Lespedeza cuneata) pellets, in reducing the post-ingestive effects of fescue toxicosis in steers. Over two summers,12 steers were assigned to either Schedonorus arundinaceous (LES) or LES mixed with polyethylene glycol (LES + PEG) as a positive control for 12 wk. Body weight, hair retention score, rectal and extremities temperatures, cortisol concentrations, and lumen area of caudal arteries were collected at 4-wk intervals. Data were analyzed using a mixed-effect ANOVA test in SAS Studio 3.5. Steers on the LES diet exhibited significantly less (P < 0.05) hair retention scores compared with those on the LES + PEG diet. In 2021, steers on the LES diet showed greater (P = 0.0101) ADG, while in 2022, there was no difference (P = 0.9916) in ADG between the treatments. Steers on the LES diet displayed greater (P = 0.0332) tail skin temperatures and decreased (P < 0.0001) rectal temperatures compared with those on the LES + PEG diet. Hair cortisol concentrations were greater (P < 0.05) in steers on the LES + PEG diet than in those on the LES diet. Additionally, steers supplemented with the LES + PEG diet showed a 21.2% smaller caudal artery lumen area compared with those on the LES diet (P < 0.01). These findings underscore the potential of CTs in reducing the post-ingestive effects of fescue toxicosis. However, further research is needed to explore the complex mechanisms underlying these effects, establish the long-term efficacy of such interventions, and extend the investigation to include a broader range of physiological parameters affecting livestock health and performance. [ABSTRACT FROM AUTHOR]

Grazing cover crops (CC) could provide an economic incentive to increase adoption rates in the southeastern United States. However, understanding grazing effects on soil properties is lacking for most soils of the region. Effects of grazing or rolling a cereal rye (Secale cereale L.) CC prior to no-till planting cotton (Gossypium hirsutum L.) were determined in 2009 after 4 yr on Cecil soil, in the Southern Piedmont near Watkinsville, GA. The four catchments had a previous long history of no-till cropping with CC. Wet spring conditions in 2009 resulted in visible surface roughness from cattle hooves. Average soil penetration resistance (PR) for the 0- to 30-cm profile was 14% greater following rye CC grazing than rolling (1.95 vs. 1.53 MPa) and was still apparent the following February (1.86 vs. 1.58 MPa) after cotton harvest. Increases in PR at 2.5- to 7.5- and 7.5- to 15-cm soil depths were observed following CC grazing but not rolling. Depth to 2 MPa resistance, considered sufficient to impede root growth, was similar for CC grazing and rolling treatments in March prior to grazing but decreased in the grazed treatment to 10.7 cm in May and 15.6 cm in February. Seasonal runoff data for 2006-2009 indicated no differences between grazed and rolled CC management. We concluded that grazing CC for short periods under wet conditions presents a risk of short-term negative effects even for Southern Piedmont soils where a long history of conservation tillage and CC has improved soil quality. [ABSTRACT FROM AUTHOR]

Land use alteration such as livestock grazing can affect water quality in habitats of at-risk wildlife species. Data from managed wetlands are needed to understand levels of exposure for aquatic life stages and monitor grazing-related changes afield. We quantified spatial and temporal variation in water quality in wetlands occupied by threatened Oregon spotted frog (Rana pretiosa) at Klamath Marsh National Wildlife Refuge in Oregon, United States (US). We used analyses for censored data to evaluate the importance of habitat type and grazing history in predicting concentrations of nutrients, turbidity, fecal indicator bacteria (FIB; total coliforms, Escherichia coli (E. coli), and enterococci), and estrogenicity, an indicator of estrogenic activity. Nutrients (orthophosphate and ammonia) and enterococci varied over time and space, while E. coli, total coliforms, turbidity, and estrogenicity were more strongly associated with local livestock grazing metrics. Turbidity was correlated with several grazing-related constituents and may be particularly useful for monitoring water quality in landscapes with livestock use. Concentrations of orthophosphate and estrogenicity were elevated at several sites relative to published health benchmarks, and their potential effects on Rana pretiosa warrant further investigation. Our data provided an initial assessment of potential exposure of amphibians to grazing-related constituents in western US wetlands. Increased monitoring of surface water quality and amphibian population status in combination with controlled laboratory toxicity studies could help inform future research and targeted management strategies for wetlands with both grazing and amphibians of conservation concern. [ABSTRACT FROM AUTHOR]

Native pollinators are important for providing vital services in agroecosystems; however, their numbers are declining globally. Bees are the most efficient and diverse members of the pollinator community; therefore, it is imperative that management strategies be implemented that positively affect bee community composition and health. Here, we test responses of the bee and flowering plant communities to land management treatments in the context of grasslands in the upper Midwestern United States, a critical area with respect to bee declines. Twelve sites were selected to examine floral resources and wild bee communities based on three different types of grasslands: tallgrass prairie remnants, ungrazed restorations, and grazed restorations. Total bee abundance was significantly higher in ungrazed restorations than remnants, but there were no significant differences among grasslands in community composition or Shannon diversity. Across the three grassland types we also examined mass and lipid stores as nutritional health indicators in three sweat bees (Halictidae), Augochlora pura , Agapostemon virescens , and Halictus ligatus. Although there were no differences in lipid content, total average bee mass was significantly higher in Ag. virescens collected from ungrazed restorations as compared to remnants. Floral abundance of native and non-native species combined was significantly higher in grazed restorations compared to remnants and ungrazed restorations. However, ungrazed restorations had higher abundance and richness of native flowering ramets. These data suggest that bee abundance and nutrition are driven by high abundance of native flowering plant species, rather than total flowering plants. [ABSTRACT FROM AUTHOR]

• Model captured seasonal and regional variability of zooplankton observation dataset. • Modelled zooplankton biomass was highest in regions adjacent to areas of high mixing. • Zooplankton grazing was high in mixed regions despite low primary productivity. We used a three-dimensional coupled biophysical model to examine zooplankton dynamics in the Salish Sea, NE Pacific. First, we evaluated the two zooplankton classes of the SalishSeaCast model using a transboundary zooplankton dataset comprised of observation data from the Canadian and United States waters of the Salish Sea from 2015 to 2019. Model zooplankton classes correspond to micro- and meso-zooplankton whose biomass is tightly coupled to phytoplankton through modelled food web dynamics (Z1) and mesozooplankton with life cycle-based seasonal grazing impacts (Z2). Overall, the model effectively captured seasonal patterns in observed biomass, although with slightly higher biomass estimates for both Z1 and Z2 (Bias = 0.10 and 0.08 g C m−2, respectively). Model fit varied regionally, with a weaker model fit being observed in nearshore regions. In addition, an autumn peak in Z2 was observed in the model, but not in the observations, suggesting some seasonal variations in model fit. Following the model evaluation, we used the model to determine seasonal and regional patterns of zooplankton grazing. Seasonally, the main peak in modelled zooplankton biomass increased in April or May in most of the regions defined within the Salish Sea and was driven by grazing on diatoms. Regionally, depth-integrated zooplankton biomass was consistently highest in areas adjacent to regions of strong tidal mixing. In addition, model-based zooplankton grazing was highest in the tidally mixed regions where phytoplankton biomass was high due to advection into the region despite low primary productivity. Our model-based results provide an opportunity to examine bottom-up food web processes at spatio-temporal scales not achievable with in situ sampling and help to elucidate key drivers of lower trophic level dynamics within the Salish Sea. [ABSTRACT FROM AUTHOR]

Focuses on the diversity and abundance of grasses in the western United States. Importance of grasses on domestic livestock and wildlife; Impact of grazing animals to the ecosystem; Improvement of pasture forages by breeding.

Tall fescue, the predominant southeastern United States cool-season forage grass, frequently becomes infected with an ergot alkaloid-producing toxic endophyte, Epichloë coenophialum. Consumption of endophyte-infected fescue results in fescue toxicosis (FT), a condition that lowers beef cow productivity. Limited data on the influence of ergot alkaloids on rumen fermentation profiles or ruminal bacteria that could degrade the ergot alkaloids are available, but how FT influences the grazing bovine fecal microbiota or what role fecal microbiota might play in FT etiology and associated production losses has yet to be investigated. Here, we used 16S rRNA gene sequencing of fecal samples from weaned Angus steers grazing toxic endophyte-infected (E+; n=6) or nontoxic (Max-Q; n=6) tall fescue before and 1, 2, 14, and 28 days after pasture assignment. Bacteria in the Firmicutes and Bacteroidetes phyla comprised 90% of the Max-Q and E+ steer fecal microbiota throughout the trial. Early decreases in the Erysipelotrichaceae family and delayed increases of the Ruminococcaceae and Lachnospiraceae families were among the major effects of E+ grazing. E+ also increased abundances within the Planctomycetes, Chloroflexi, and Proteobacteria phyla and the Clostridiaceae family. Multiple operational taxonomic units classified as Ruminococcaceae and Lachnospiraceae were correlated negatively with weight gains (lower in E+) and positively with respiration rates (increased by E+). These data provide insights into how E+ grazing alters the Angus steer microbiota and the relationship of fecal microbiota dynamics with FT. IMPORTANCE Consumption of E+ tall fescue has an estimated annual $1 billion negative impact on the U.S. beef industry, with one driver of these costs being lowered weight gains. As global agricultural demand continues to grow, mitigating production losses resulting from grazing the predominant southeastern United States forage grass is of great value. Our investigation of the effects of E+ grazing on the fecal microbiota furthers our understanding of bovine fescue toxicosis in a realworld grazing production setting and provides a starting point for identifying easy-to-access fecal bacteria that could serve as potential biomarkers of animal productivity and/or FT severity for tall fescue-grazing livestock. [ABSTRACT FROM AUTHOR]

• Literature review found few papers addressing plant-soil dynamics in organic pastures. • Little evidence that organic pasture management results in altered plant or soil processes. • Principles of managed grazing for non-organic pastures critical for organic livestock management. Organic livestock production in the U.S. requires that a significant amount of feed comes from grazed pasture. While principles of grazing management for temperate grasslands are well known, organic livestock production may result in unique plant-soil dynamics with ramifications for farmer decision-making and management. We reviewed the literature for direct or indirect evidence that organic pasture management results in altered plant-soil dynamics and assessed whether organic management might necessitate modifications or additions to managed grazing principles. The literature directly addressing these questions is sparse. We found some evidence that organic management can stimulate soil biota but no evidence for grassland yield, soil stocks, or soil transformation rate differences between organic and non-organic pastures. Given the constraint on fertilizer and herbicide inputs in organic management, established principles of managed grazing – rotating livestock frequently through paddocks such that plants are uniformly grazed but left with significant residual biomass and time for regrowth – are critical for maintaining dense, productive swards in organic pasture management. [ABSTRACT FROM AUTHOR]

The extant and often burgeoning feral horse herds in several countries have become a contentious issue for animal welfare and biological conservation. The emotions humans express for horses have escalated to a divisive level that has consequently hindered administrative actions. While human emotions are important for resource management as motivation enhancing awareness and action, emotions may hinder management due to a lack of reconciliation with data. For the emotions surrounding feral horse management, I conducted a critical review of the history of horse domestication, the contemporary understanding of the psychology of human-horse relationships, and the current status of feral horse ecology and management. Domestication of horses ∼5500 years ago in Eurasia coupled humans with horses in a symbiotic relationship where the two functioned almost as one. This process enabled the spread of human genes and food production. Human reliance on horses became a working relationship founded on trust and respect that facilitated bonding via overcoming adversity that likely deepened human-horse emotional connections – a coevolutionary process for which there are few analogous examples. While human reliance on horses has waned in developed countries recently, it has been humans that have largely facilitated the spread of horses through space and time. Contextualized with contemporary data, feral horse populations in the United States and Australia have increased dramatically. Consequently, horses have had negative effects on native ecosystems in some areas, and degradation has led to emaciated horses in some areas. The public often expresses opposition to horse management, likely out of an innate emotional reaction. However, the emotional co-evolutionary history, coupled with cognitive appraisal of contemporary data including horse welfare, offers an opportunity for emotional regulation and de-escalation for this contentious issue. [ABSTRACT FROM AUTHOR]

• Grazing was the predominant diurnal behavior shown by Kiko wethers in southern-pine silvopasture. • Kiko wethers did not show any pine debarking behavior throughout the observation period. • Grazing was the predominant diurnal behavior during the post-midday period while lying was predominant during midday. • Kiko wethers were found safe to integrate in southern-pine silvopastures during the warm-season grazing period. Goats are the common grazing livestock integrated into the silvopasture system. Previous grazing studies with goats in southern-pine silvopastures showed significant debarking of pine trees during the cool-season grazing period. However, goats' behavior in this system during the warm-season grazing period has not been previously reported. The objective of the study was to determine the diurnal behavior and distribution pattern of Kiko wethers in southern-pine silvopastures planted with warm-season forages. The study was conducted at the Atkins Agroforestry Research and Demonstration Site, Tuskegee University, Tuskegee, Alabama, USA. The study site consisted of three silvopasture plots (0.4-ha each) comprising 12-year-old longleaf (Pinus palustris Mill.) and loblolly (Pinus taeda L.) pines, with a tree density of 402 trees ha−1 (loblolly: longleaf ratio – 1.27). Study plots were divided into three zones, and three different warm-season forages were grown in these zones. Forage samples were collected and analyzed for productivity and quality. Ten Kiko wethers (2.75–2.90-year-old, 62.9 ± 1.56 kg BW) were rotationally stocked in the study plots, and their diurnal behavior and distribution pattern studied when they were in each study plot. Data were analyzed using Kruskal–Wallis rank-sum test in R-package. Grazing was the predominant diurnal behavior (46%) shown by Kiko wethers followed by staying in shelters (22%) and lying (17%). Wethers did not show any pine debarking behavior. Wethers spent predominant diurnal time in Zone 3 (42%) planted with sericea lespedeza (Lespedeza cuneata (Dum. Cours.) G. Don) that had the highest quality forages followed by Zone 1 (31%) planted with bahiagrass (Paspalum notatum Flueggé). Kiko wethers could be safe to stock in southern-pine silvopastures containing 12-year-old trees during the warm-season grazing period. [ABSTRACT FROM AUTHOR]

Populations of grassland songbirds continue to decline, and grasslands devoted to conservation are rare across the Great Plains. To gain the most value from grasslands for grassland birds, we must understand what types of management benefit these species. We evaluated the relative abundance of grassland birds on ownership types and the association of different land use activities with their abundance. We surveyed a wide range of grasslands (e.g., from idle to heavily managed, from remnant prairie to reconstructed) across western Minnesota and northwestern Iowa, USA, in 2013 and 2014. Sites surveyed covered a gradient of landscape context, management history (fire, grazing, reconstruction), and public and private ownership. We evaluated the influence of ownership and management history on the abundance of 12 species of grassland birds by comparing Akaike's Information Criterion values of linear models that included the variables of interest to models that included only local and landscape habitat factors. Ownership explained additional variation in bird abundance beyond local and landscape variables for 7 of the 12 species, and 5 species were more common on private lands. Fire or grazing history explained variation in bird abundance for 11 species, and 7 species had greater abundance on remnant prairie than on reconstructed grassland. For all but 1 species, ownership and management factors significantly improved models above a base model of local and landscape variables typically used to predict abundance. Our results suggest remnant prairie plays an important role for grassland birds, and that grazing could be a tool to increase abundance of some grassland bird species in the region. Furthermore, tracking management history of public lands in a consistent and accessible way could help improve landscape‐based models for these species. © 2018 The Wildlife Society. Land ownership and management explained substantial variability in grassland bird abundance in western Minnesota and northwestern Iowa in 2013 and 2014. In particular, a number of species responded positively to grazing, and remnant native prairie supported greater abundance of many grassland bird species than reconstructions. [ABSTRACT FROM AUTHOR]

Describes the lives of nomads, sheep ranchers and other settlers along the Green River of Wyoming, Utah and Colorado. Clashes between nomadic sheepmen and stable cattlemen; Approval of the Taylor Grazing Act in 1934; Wild-horse running; Livestock industry.

• We proposed a novel hybrid GPP model framework coupling LUE with ML. • Hybrid GPP models take ML complementary to LUE framework. • Hybrid GPP models outperform pure ML models under extreme surface conditions. Light use efficiency (LUE) model was established to estimate gross primary production (GPP) for understanding the carbon-climate feedbacks of the terrestrial ecosystems. However, water constraints in LUE models can cause large uncertainties in GPP estimates, especially in semiarid grasslands where water is a key forcing factor for multiple ecosystem processes. Here, we proposed a novel LUE-Gradient Boosting Regression Trees (GBRT) model framework where water scalar is derived from five different water constraints for improving the estimates of grassland GPP over the conterminous United States (CONUS). The performance of LUE-GBRT and ten other GPP models [i.e., LUE-RF, LUE-ERT, GBRT, RF, ERT, LUE-f EF , LUE-f VPD , LUE-f LSWI , LUE-f SM , and LUE-f LST ] was evaluated against data from eddy covariance (EC) observations at 25 measurement sites over the CONUS domain from 2000 to 2021. We found that LUE-GBRT improved grassland GPP estimates at all EC sites and yielded the highest Kling-Gupta efficiency (0.85) and the lowest root-mean-square error (1.4 g C m−2 d−1) when compared with the five individual GPP models. LUE-GBRT also showed a superior performance compared to LUE-RF and LUE-ERT. Compared with GBRT, the improvements were particularly from the responses to extreme surface conditions that were better characterized and estimated. An innovation of this method is that LUE-GBRT takes machine learning complementary to the physical-based LUE framework for an optimal junction between GPP physical process and model accuracy. [ABSTRACT FROM AUTHOR]

Protected areas provide some of the last refuges for Asian elephants in the wild. Managing these areas for elephants will be critical for elephant conservation. Scientists know little about elephant habitat use in Asia and how invasive species or livestock grazing influence habitat use. We studied these issues in two protected areas in Sri Lanka, Udawalawe National Park and Hurulu Eco-Park. These areas contain some of Sri Lanka's largest remaining grasslands. These grasslands are threatened by the invasive and toxic shrub, Lantana camara , and are used for illegal livestock grazing. To measure habitat use by elephants and livestock, we conducted dung surveys along over 50 km of transects stratified across grassland, scrub, and forest. We surveyed 159 vegetation plots along these transects to assess plant composition, and mapped habitat types based on satellite images. We used mixed-effect models to determine the relative importance of habitats, livestock presence, and plant associations for elephant use. Elephant presence was greatest in scrub and grassland habitats, positively associated with both livestock presence and short graminoids, and unaffected by L. camara , which was widespread but at low densities. Given the importance of these areas to elephants, we recommend a precautionary management approach that focuses on curbing both illegal grazing and the spread of L. camara . [ABSTRACT FROM AUTHOR]

• Thinning + burning increased canopy openness, herbaceous cover, and shrub density. • Low-intensity grazing did not improve vegetation structure more than thinning + burning. • Restoration shifted the plant community from woodland species to savanna associates. Temperate savannas are unique, biodiverse ecosystems that have undergone extensive habitat conversion globally. In the midwestern United States, 99% of historic oak savanna area has been lost. Most remaining patches of savanna are degraded due to woody encroachment following the removal of both fire and large herbivore disturbances from the landscape. Restoring degraded savanna remnants is challenging because we lack an understanding of how to best apply contemporary restoration tools to mimic historic disturbance dynamics. To that end, we evaluated the outcomes of ongoing oak savanna restorations that have received a gradient of restoration actions: 1) no management, 2) tree thinning, 3) thinning + burning, and 4) thinning + burning + cattle grazing. We assessed several metrics of restoration success including canopy, shrub, herbaceous, and non-native cover, herbaceous diversity, and plant community composition. We found that layering restoration approaches achieved certain, but not all, structural vegetation goals. Compared to no management, thinning and fire successfully increased canopy openness, herbaceous cover, and herbaceous diversity, but had the unwanted effect of increased shrub cover. The addition of low-intensity cattle grazing did not improve structural outcomes. We also found that each restoration treatment left a unique signature on understory plant community composition. Unmanaged and thin-only treatments were characterized by tree saplings and woodland herbs, while burned and grazed treatments were defined by shrubs and savanna-associate species. We conclude that reintroducing multiple disturbances does not guarantee the successful restoration of disturbance-dependent ecosystems such as oak savannas. Restoration outcomes are not dictated by how many management approaches are applied, but rather, the nuances of how they are applied such as burn season and livestock density. [ABSTRACT FROM AUTHOR]

Native grasses, such as switchgrass (SG; Panicum virgatum L.), big bluestem (BB; Andropogon gerardii Vitman), indiangrass (IG; Sorghastrum nutans Nash), and eastern gamagrass (EG; Tripsacum dactyloides [L.] L.) may be capable of providing desirable summer forage for cattle as well as a source of biomass for renewable energy. To evaluate that potential, experiments were conducted at 2 locations in Tennessee comparing weaned beef (Bos taurus) steers (268 ± 25 kg initial BW) during early-season grazing (Early; 30 d, typically corresponding to May, followed by postdormancy biomass harvest) and full-season grazing (Full, mean duration = 98 d). For Exp. 1, which compared SG, a blend of BB and IG (BBIG), and EG, ADG was greater (P < 0.05) for BBIG (1.02 kg/d) than SG (0.85 kg/d), and both were greater (P < 0.05) than EG (0.66 kg/d). Grazing days for SG and EG were similar (389 and 423 animal unit days [AUD]/ha, respectively) and exceeded (P < 0.05) that of BBIG (233 AUD/ha) during Full. In Exp. 2 (SG and BBIG only), rates of gain were comparable to that of Exp. 1, but AUD were 425 (SG) and 299 (BBIG) AUD/ha. Such rates of gain and grazing days indicate that these grasses can provide desirable summer forage for growing cattle. Early produced 211 to 324 kg BW gain/ha, depending on experiment and forage, followed by dormant-season harvests of 7.5 to 10.5 Mg/ha of biomass, indicating a potential for beef cattle forage and biomass production on the same land resource. Native grasses provided productive summer pasture and good rates of gain on growing cattle and could contribute to forage programs, especially where cool-season grasses currently predominate. [ABSTRACT FROM AUTHOR]

Natural disturbances are critical ecosystem processes, with both ecological and socioeconomic benefits and disadvantages. Large herbivores are natural disturbances that have removed plant biomass for millions of years, although herbivore influence likely has declined during the past thousands of years corresponding with extinctions and declines in distributions and abundances of most animal species. Nonetheless, the conventional view, particularly in eastern North America, is that herbivory by large wild herbivores is at unprecedented levels, resulting in unnatural damage to forests. Here, we propose consideration of large herbivores as a natural disturbance that also imparts many crucial ecological advantages, using white-tailed deer (Odocoileus virginianus), the only wild large herbivore remaining throughout the eastern U.S., as our focal species. We examined evidence of detrimental effects of browsing on trees and forbs. We then considered that deer contribute to both fuel reduction and ecological restoration of herbaceous plants and historical open forests of savannas and woodlands by controlling tree and shrub densities, mimicking the consumer role of fire. Similarly to other disturbances, deer disturbance 'regimes' are uneven in severity across different ecosystems and landscapes, resulting in heterogeneity and diversity. In addition to biodiversity support and fuel reduction, socioeconomic benefits include >$20 billion dollars per year by 10 million hunters that support jobs and wildlife agencies, non-consumptive enjoyment of nature by 80 million people, cultural importance, and deer as ecological ambassadors, whereas costs include about $5 billion and up to 450 human deaths per year for motor vehicle accidents, along with crop damage and disease transmission. From a perspective of historical ecology rather than current baselines, deer impart a fundamental disturbance process with many ecological benefits and a range of socioeconomic effects., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Published by Elsevier B.V.)

Privately owned grazing lands comprise 52% of all grazing lands in the United States. Livestock production is the primary economic source of income from these lands; however, improved management strategies can be implemented to not only sustain this agroecosystem, but enhance the natural resource to provide new and innovated ecosystem services and goods. To sustain this resource, grazing strategies should be designed to implement five basic principles: 1) provide diverse plant communities, 2) protect the soil surface, 3) eliminate overgrazing, 4) incorporate grazing management that enhances the forage harvest efficiency, and 5) create best managed ecosystems that accomplish reestablishment of historical disturbance regimes for a given region. By obtaining these principles, land owners will have the opportunity to create or enhance ecosystem services and goods that provide commodity, amenity, environmental and spiritual values essential to ranching life, the communities they live in, and the nation as a whole. Sustained ecosystems can provide food, fiber, biofuels, fish and wildlife habitat, water, improved air quality, ornamental resources, and ceremonial items to name a few. Livestock grazing is essential to sustain the ecosystems associated with rangeland, grassland and other perennial pastures. Ranchers and land managers should incorporate new grazing strategies to sustain the agroecosystem while developing potential enterprises to increase income through secondary goods and service. The ultimate goal is to provide a sustainable ecosystem that can be shared by future generations with a history that ties the land to the family and community. [ABSTRACT FROM AUTHOR]

In the Midwestern US, both forestry and agriculture advisors have advocated against combining trees and livestock for more than 50 years. This established stance poses a potential barrier to the adoption of silvopasture, an agroforestry practice that integrates grazing with trees. We conducted three focus group interviews in southwestern Wisconsin, two with foresters and agriculture professionals, and one with farmers to assess their attitudes toward silvopasture. Although resource professionals were reluctant to endorse livestock access to woodlands, they were cautiously interested in exploring silvopasture as a means to improve the management of grazing in wooded areas and as a management tool for savanna restoration. Foresters, agricultural professionals, and farmers identified similar potential benefits and concerns associated with silvopasture, and requested better information on establishment, economics, and best management practices for silvopasture in the Midwest. Their questions and concerns provide direction for future silvopasture research and outreach efforts in the Midwest. [ABSTRACT FROM AUTHOR]

ABSTRACT Grassland birds have declined more than any other guild in the United States because of loss and degradation of native grasslands. The United States Department of Agriculture Farm Bill programs have restored some native warm-season grasses (NWSG), but populations of many grassland bird species continue to decline. Market-based NWSG uses focused on hay, pasture, and biofuel feedstock may be more appealing to landowners, and may still provide grassland bird habitat on the landscape. We examined breeding grassland bird occupancy of 102 NWSG production fields including 5 treatments (control [ n = 37], grazing [ n = 7], hay [ n = 22], seed [ n = 21], and biofuel [ n = 15] production) in Kentucky and Tennessee during 2009-2010 breeding seasons. We used a robust design model in Program MARK to determine occupancy and detection rates for grassland birds. We modeled occupancy differences among treatments and sites (i.e., KY, TN), and included covariates (i.e., field-level vegetation metrics and landscape composition at 3 scales [250 m, 500 m, and 1 km]) for eastern meadowlark ( Sturnella magna), field sparrow ( Spizella pusilla), grasshopper sparrow ( Ammodramus savannarum), northern bobwhite ( Colinus virginianus), and red-winged blackbird ( Agelaius phoeniceus). Covariates that influenced occupancy included treatment (field sparrow, 2009 only), site (eastern meadowlark, grasshopper sparrow, and northern bobwhite), percent NWSG cover (positive, red-winged blackbird), and percent forest cover within 250 m (negative for eastern meadowlark, grasshopper sparrow, northern bobwhite, and red-winged blackbird) or within 1 km (negative, field sparrow). Our results suggest that forest cover in the surrounding landscape negatively influences species occupancy, and species occupancy generally did not differ among NWSG production treatments. These treatments could be an alternative means to provide grassland bird habitat within an agriculture production landscape. © 2016 The Wildlife Society. [ABSTRACT FROM AUTHOR]

Even though the cropland data layer (CDL) has been used in policy discussions it has not been independently validated using publically available information. The projects objective was to conduct an independent validation of the CDL. South Dakota was selected as a model system because it is located in a climate transition zone, wiThrow crop production being the dominant practice in eastern South Dakota and the grazing of grassland being the dominant practice in western South Dakota. High resolution imagery was used to determine land-uses (cropland, grassland, non-agricultural, habitat, and water) at 14,400 points in 2006 and 2012. Based on comparisons between the CDL and ground collected data, a confusion table was constructed and the CDL user (% false positive = 100-user accuracy) and producer (% false negatives = 100 - producer accuracy) accuracies determined. The % false positives and % false negatives are oft en referred to as Type I error and Type II error. In 2006, the CDL cropland producer accuracy (% of ground collected sites that were correctly identified) ranged from 89.2% in the east central to 42.6% in the Northwest, whereas the CDL grassland producer accuracy ranged from 95.2% in the Northwest to 38.9% in the Southeast. Similar results were reported for 2012. Grassland CDL producer and user accuracies were highest when grasslands were the dominant practice and cropland producer and user accuracies were highest when croplands were the dominant land-use. These results suggest that inherent CDL errors introduce uncertainty into land-use change calculations. [ABSTRACT FROM AUTHOR]

Pastures in the southeastern United States are dominated primarily by warm season perennials such as bermudagrass which can be low in energy. Assessment of stocker cattle performance on bermudagrass pastures overseeded with alternative warm-season forages, such as sorghum Sudan grass and cowpea, are scarce. A study was conducted during the summer of 2021 with crossbred steers (n = 72; 305 ± 2.8 kg initial BW) to investigate growth performance when grazing sorghum Sudan grass and sorghum Sudan grass intercropped with cowpea as alternatives to bermudagrass. The experiment was a randomized complete block design with 3 treatments and 3 replicates (2 ha each) per treatment. Treatments were bermudagrass (Cynodon dactylon (L.) Pers) (CON), CON overseeded with brown mid-rib sorghum Sudan grass (Sorghum bicolor L.) (SS), and SS with cowpeas (Vigna unguiculata (L.) Walp) (SSCP) planted in alternate planting passes. Forage samples were collected from 3, 0.25m2 quadrats placed randomly in the next available paddock just prior to grazing. The SSCP pastures had 3 additional randomly placed quadrats, 3 in SS and 3 in CP. Forage crude protein and neutral detergent fiber (NDF) did not differ (P >0.96 and 0.19, respectively) among treatments and averaged 9.1% and 65.6%. Pre-grazing forage mass was greater in SS and SSCP (P< 0.01) averaging 4,925, 3,460, and 1,590, in SS, SSCP, and CON, respectively. Animal gains were 1.04 in SSCP and 0.96 in SS, greater than 0.78 in CON (P< 0.01). Grazing days were greatest (P< 0.01) in CON (91 d) followed by SS (68 d), with the fewest grazing days in SSCP (60 d). Despite differences in grazing days, gain per ha, did not differ (P=0.39) among treatments, and averaged 261 kg/ha. Although SSCP and SS had fewer grazing days, gain per ha were similar among treatments due to greater ADG on SS and SSCP pastures. [ABSTRACT FROM AUTHOR]

An essay is presented which discusses why trust land agencies are not more market-oriented stewards of the land and resources. Topics include creation of state trust land agencies in the U.S. for range resource allocation, range management, private ownership to allocate resource use and public rights, and understanding the complexities of the various rules for public land agencies to reform public grazing policy.

The article focuses on several aspects of managing conflicts over the U.S. federal rangelands. Topics discussed include overview of the U.S. federal grazing system, conflict between the U.S. Bureau of Land Management (BLM) and Nevada rancher named Cliven Bundy, which resulted in transformation of the federal grazing policy, and federal grazing program administered by the U.S. Forest Service.

Dairy farms that grow more perennial vegetation as grazing pastures or conserved forages can offer many environmental benefits but may show reduced milk production relative to farms feeding higher amounts of grain and corn silage. Because yields of annual and perennial crops vary with soil type, an accurate comparison of the productive potential of these systems over county or regional scales may require taking into account spatial variation in soil quality. In this study, we present a novel approach to calculate the production from dairy systems that adjusts average crop yields to the productive potential of local soils using the National Commodity Crop Productivity Index (NCCPI). We used on-farm survey data to define confinement and grazing systems with varying amounts of perennial forage and applied our method to a sample of five counties in the northeast United States. High corn silage farm systems produced 21 to 168% more milk per hectare of farmland than grazing-based farm systems, but variation among counties was greater than variation among systems, with the best (Lancaster, PA) producing as much as 5.3 times more than the least (Orange, VT). Adjusting yields for soil productivity had smaller effects on milk production than differences in farm system or county. On average, grazing farm systems generally produced slightly more milk when yields were adjusted using the NCCPI (8%) while high corn silage systems showed a moderate decrease (13%). Compared to scenarios of all local crop production, scenarios with unlimited corn and soybean imports often more than doubled county-scale milk production. Restricting grain imports to prevent excess phosphorus resulted in a 3–15% decrease in milk production relative to unlimited imports, but still produced far more milk than in the all local production scenarios. Sensitivity analysis of the model showed that milk production in each county was very responsive to changes in perennial forage yields (especially for grazing systems), responsive to changes in average daily milk production per cow, and generally not responsive to changes in the productive lifetime of lactating cows. This study demonstrates a persistent tradeoff between perenniality and production in dairy systems, but suggests that opportunities may exist to maintain current milk production levels in the Northeast while also expanding land cover in perennial vegetation. [ABSTRACT FROM AUTHOR]

The article discusses the water challenges and need to expand the watershed with sustainability to meet the challenges in the Twenty-First Century in Colorado. It mentions a report by geologist John Wesley Powell "Report on the Lands of the Arid Region of the United States" which reveals that the western region of the U.S. are not suitable for agriculture and grazing. It also mentions the need to strategic and collaborative approaches to water management.

Competition between livestock and wild ungulates is commonly perceived to occur on shared rangelands. In the Henry Mountains ( HM) of Utah, a free-ranging population of bison Bison bison has raised concerns among ranchers holding grazing permits on these public lands. Bison are the most conspicuous potential competitors with cattle, but lagomorphs (mainly jackrabbits Lepus californicus) are also abundant in this area. The local ranching community is applying political pressure on state and federal agencies to resolve 'the bison problem', but the relative grazing impacts of bison, cattle and lagomorphs have not previously been quantified., We constructed 40 grazing exclosures (each 5·95 m2) in the conflict area: 20 excluded bison + cattle ('partial') and 20 excluded bison + cattle + lagomorphs ('full'). All exclosures, each with a paired open reference plot, were monitored for 1 year, and above-ground plant production was measured. GPS telemetry (bison) and scheduled grazing (cattle) allowed visitation to be quantified for each ungulate species based on the number of 'animal days' in the area. Rancher perceptions of wildlife-cattle interactions were recorded in a questionnaire survey., Ranchers perceived bison as a high-level competitor with cattle, whereas lagomorphs were perceived as low-level competitors., Grazed reference plots yielded an average (± SE) of 22·7 g m−2 (±5·16) of grass, compared to 36·5 g m−2 (±7·33) in the partial exclosures and 43·7 g m−2 (±7·61) in the full exclosures. Exclusion of large herbivores thus resulted in a 13·8 g m−2 increase in grass biomass relative to the reference plots ( P = 0·005), with the additional exclusion of lagomorphs resulting in a further 7·18 g m−2 increase ( P = 0·048)., Overall, lagomorphs accounted for 34·1%, bison 13·7% and cattle 52·3% of the total grass biomass removed by all herbivores on the shared range., Synthesis and applications. Cattle face a greater competitive challenge from lagomorphs than from bison in the study area. This case study illustrates the need for science-based management of social-ecological systems in which even long-term resource users might underestimate the complexities of trophic interactions. Attention should be redirected at the lagomorphs and their main predators, coyotes Canis latrans, which are currently subject to population control. To reduce negative perceptions among local ranchers, options should be explored to incorporate benefit-sharing into the management of the bison population. [ABSTRACT FROM AUTHOR]

Management for biodiversity and other ecosystem services from North America's rangelands has received increasing attention as recognition of the societal value of those services and payment mechanisms for them have grown. This, combined with adverse effects of livestock management on North American rangeland biodiversity and predictions of a warmer and drier climate reducing rangeland productivity, has led some rangeland scientists to call for a paradigm shift from utilitarian-driven management to biodiversity conservation management. A challenge for rangeland science is to describe management changes required for this shift and to elucidate consequent ecological and economic tradeoffs. On the basis of two criteria, direct alteration of biodiversity and alteration of one or more drivers of biodiversity, a framework of ten ecological conditions is proposed for making the transition from livestock-centered management toward biodiversity-centered management on Great Plains rangelands: (1) composition and productivity of plant communities; (2) herbivory patterns; (3) fire regimes; (4) habitat contiguity; (5) stream hydrology; (6) temporal ecological variability; (7) herbivorous mammal communities; (8) fate of ungulate production; (9) apex predators; and (10) size of management units. Reflecting trends in rangelands elsewhere around the world, a shift toward management for biodiversity on the Great Plains may be facilitated by changes underway in land ownership and by a potentially increasing number of landowners for whom livestock production is of secondary importance to lifestyle and natural amenity benefits from the land. [ABSTRACT FROM AUTHOR]

The article offers information on a research facility called Central Plains Experimental Range in Colorado. Topics discussed include the research conducted in the site wherein livestock, conservation and land management approaches are being studied by livestock technicians, ranchers and data managers, and highlights the use of adaptive grazing management which involves sustainable management of lands and graze herds.

Assessment of beef cow energy balance and efficiency in grazing-extensive rangelands has occurred on a nominal basis over short time intervals and has not accounted for the complexity of metabolic and digestive responses; behavioral adaptations to climatic, terrain, and vegetation variables; and documentation of the effects of nutrient form and supply to grazing cattle. Previous research using pen-fed cows demonstrated differences (P <0.01) in efficiency of weight change ranging from 135 to 58 g/Mcal ME intake. Furthermore, variation in efficiency of ME use for tissue energy gain or loss ranged from 36% to 80%. In general, energy costs for maintenance, tissue accretion, and mobilization were greatest in Angus-based cows, intermediate in Brahmanand Hereford-based cows, and least in dairy-based cows. The most efficient cattle may reflect the types that are successful in semiarid grazing environments with low input management. Successful range cattle systems are likely the result of retention of animals that best adapted to the grazing environment and thus were potentially more efficient. Animals exposed to a variety of stressors may continually adapt, so energy expenditure is reduced and may tend to depart from the modeled beef cow in the 1996 NRC Beef Cattle Requirements. Critical factors comprising cow lifetime achievement, including reproductive success, disease resistance, and calf weaning weight, may be driven by cow total energy utilization in energy-limiting environments. Therefore, energy adjustments for adapted cattle within these landscapes and seasonal BW changes can alter seasonal NEm requirements. Evaluated studies indicate that in static grazing environments, NRC prediction fitness was improved compared with predictions from dynamic systems where cattle were influenced less by management and more by environmental conditions. Preliminary herd analyses cast doubt on the accuracy of NRC BCS descriptions representing NEm requirements of adapted females utilizing semiarid rangelands. Possible gaps are proposed that could be the basis for prediction inaccuracies. A more complete understanding of mechanisms contributing to productivity in the field than the current model predicts will improve future models to better simulate energetic accountability and subsequent female performance. [ABSTRACT FROM AUTHOR]

Svejcar et al. (Environ Manage, ) offered several perspectives regarding Beschta et al. (Environ Manage 51:474-491, )-a publication that addressed the interacting ecological effects of climate change and domestic, wild, and feral ungulates on public lands in the western United States (US)-by largely focusing on three livestock grazing issues: (1) legacy versus current day impacts; (2) grazing as a fire reduction tool; and (3) the complexity of grazing. Regarding these issues, we indicate that (1) legacy effects to western ecosystems were indeed significant and contemporary livestock use on public lands generally maintains or exacerbates many of those effects; (2) livestock grazing has been a major factor affecting fire frequency, fire severity, and ecosystem trajectories in the western US for over a century; and (3) the removal or reduction of grazing impacts in these altered ecosystems is the most effective means of initiating ecological recovery. Svejcar et al. (Environ Manage, ) offer no evidence that livestock use is consistent with the timely recovery of grazing-degraded uplands, riparian areas, or stream systems. We thus conclude that public-land ecosystems can best persist or cope with a changing climate by significantly reducing ungulate grazing and related impacts. [ABSTRACT FROM AUTHOR]

Abstract: There is little information available on the species dynamics of eimerian parasites in grazing cattle in the central Appalachian region of the United States. Therefore, the objective of this study was to describe the level of infection and species dynamics of Eimeria spp. in grazing beef cattle of various age groups over the course of a year in the central Appalachian region. Rectal fecal samples were collected from male and female calves (n =72) monthly from May through October 2005, heifers only (n =36) monthly from November 2005 to April 2006, and cows (n =72) in May, July, and September, 2005. Eimeria spp. oocysts were seen in 399 of 414 (96%) fecal samples collected from the calves from May through October. Fecal oocysts counts (FOC) in the calves were lower (P <0.05) in May than all other months and no significant differences were detected from June through September. Eimeria spp. oocysts were detected in 198 of 213 (92%) of fecal samples collected from the 36 replacement heifers monthly from November to April and monthly mean FOC did not differ during this time period. The prevalence of oocyst shedding increased to 100% in calves in September and remained near 100% in the replacement heifers during the sampling period. Eimeria spp. oocysts were also detected in 150 of 200 (75%) samples collected in May, July, and September from the cows and mean FOC did not differ significantly over the sampling period. Eimeria spp. composition was dominated by Eimeria bovis in fecal samples collected from calves, replacement heifers and cows. Mixed Eimeria spp. infections were, however, common in all groups and 13 Eimeria spp. oocysts were identified throughout the sampling period. [Copyright &y& Elsevier]

Commercial milking of sheep is a new agricultural industry in the United States starting approximately 30 years ago. The industry is still small, but it is growing. The majority of the sheep milk is used in the production of specialty cheeses. The United States is the major importer of sheep milk cheeses with 50 to 60% of annual world exports coming to the United States during the past 20 years. Therefore, there is considerable growth potential for the industry in the United States. The only dairy sheep research flock in North America is located at the Spooner Agricultural Research Station of the University of Wisconsin-Madison. The research program started in 1993 and has been multifaceted; dealing with several areas important to commercial dairy sheep farmers. The East Friesian and Lacaune dairy breeds were compared and introduced to the industry through the research program. Both dairy breeds produced significantly more milk than traditional meat-wool breeds found in the U.S., but the two breeds differed in their production traits. East Friesian-cross ewes produced more lambs and slightly more milk than Lacaune-cross ewes whereas Lacaune-cross ewes produced milk with a higher percentage of fat and protein than East Friesian-cross ewes. Lactation physiology studies have shown that ewes with active corpora lutea have increased milk yields, oxytocin release during milking is required to obtain normal fat percentages in the milk, large udder cisterns of dairy ewes can allow for increased milking intervals, and short daylengths during late pregnancy results in increased milk yield. In the nutrition area, legume-grass pastures and forages with a higher percentage of legume will result in increased milk production. Grazing ewes respond to additional supplementation with increased milk yield, but it is important to match the supplement to the quality of the grazing. Ewes on high quality legume-grass pastures that are high in rumen degradable protein respond with increased milk production to supplements high in energy and/or high in rumen undegraded protein. [ABSTRACT FROM AUTHOR]

This study used benthic surveys and manipulative experiments to examine (1) if boundaries between kelp forests and urchin barrens exist at multiple locations spanning the Aleutian Archipelago, (2) if these boundaries are spatially stable, and (3) how changes in algal density within the kelp forests influence the ability of urchins to invade them. Our results demonstrate that sharply punctuated kelp forest-urchin barren boundaries occur throughout the Archipelago, and they are spatially stable for at least 2 years. Further, when all macroalgae were experimentally removed from the kelp forest side of the boundaries, urchins rapidly moved into these clearings and excluded macroalgae for up to 2 years. However, these movements were not observed where 75% or less of the macroalgae was removed (leaving 25% or more in place), suggesting that even low macroalgal abundances can prevent urchins from invading the kelp forests. Further, urchin densities were negatively related to kelp density, again indicating that kelp can reduce urchin densities. While the ability of urchins to overgraze kelp forests is widely known, our results indicate that kelp can inhibit urchins, that these inhibitory influences are a widely recurrent phenomenon, and that this interaction is important to maintaining kelp forests across the Aleutians. [ABSTRACT FROM AUTHOR]