Rotational grazing studies have produced mixed results related to animal performance (weight gain), which has contributed to producer uncertainty regarding grazing management decisions. To enhance decision-support for producers, we improved algorithms in the Agricultural Policy/Environmental eXtender (APEX) model to better represent cattle weight gain in real-world rangeland conditions under two grazing management strategies. Simulated weight gain and related forage effects were evaluated with experimental data from 2014 to 2018 under two grazing strategies. The traditional rangeland management strategy used continuous season-long grazing stocked at a moderate level. The collaborative adaptive rangeland management strategy employed grazing with one large herd rotated using a sequence developed by a stakeholder group with movement between pastures driven by predetermined decision triggers. For each grazing strategy, yearling steers grazed from mid-May to October on ten 130-ha pastures. With the APEX modifications, daily weight gain was adequately simulated for both continuous (traditional rangeland management) grazing and management intensive rotational (collaborative adaptive rangeland management) grazing. Dry matter intake, total digestible nutrients, and temporal distribution of dry matter intake were the primary influencers of cattle performance (weight gain). Once shown to be accurate, we used APEX to evaluate several management alternatives (i.e., stocking rate, rotation interval, and rotation decision criteria) to showcase its decision support capabilities. These important enhancements increase the utility of APEX in semiarid environments, such as the western Great Plains, in providing science-based rangeland decision support to ranchers, agency land managers, and policy makers.

Drought is frequent on grasslands, often creating patches with reduced coverage of green vegetation that influence the trajectory of vegetation recovery following drought. Limiting the extent and sizes of low-cover patches thus should be a target of adaptive management on grazed grasslands, but quantifying patch sizes requires measurements at small spatial resolution. We used airborne (unmanned aerial vehicle) estimates of green plant cover at 8-cm spatial resolution to quantify the aerial extent and patch sizes of mesic grassland in central Texas, United States in which green plant cover was eliminated during a growing-season (seasonal) drought in each of two grazing treatments (rotational, continuous). Remote measurements of the normalized difference vegetation index (NDVI), indicative of plant biomass, were then used to compare postdrought recovery of vegetation in patches that lacked versus retained green plant cover during drought (not green vs. green). Below-average precipitation from April through July 2018 (41% of the mean) eliminated green plant cover from 5%-12% of grassland area. Fractional coverage of the not-green area was greater by a factor of 2 under continuous grazing. Formerly not-green patches exhibited full recovery in seasonal mean values of NDVI during the year following drought in both grazing treatments. NDVI recovery was facilitated by a marked increase in abundance of early-season annual species in pasture dominated by summer-maturing perennial grasses. Spring NDVI of formerly not-green patches was greatest under continuous grazing during 2 post-drought yr, implying that annual species limited colonization of perennial vegetation more under continuous than rotational grazing. Our results imply that managers can facilitate drought recovery of perennial vegetation in mesic grassland by 1) adaptively managing grazing to reduce patch sizes of grassland that suffer complete loss of green plant cover and 2) employing rotational grazing to eliminate grazing pressure for several consecutive months annually following drought.

Pastoralists inhabiting the rangeland of northern Iran are threatened by dangers like drought, cold, floods, livestock diseases, and livestock price fluctuations. Insurance offers them a promising mechanism to manage their activities. However, information on the willingness of pastoralists to take the risk or accept insurance remains unknown. To answer this question, a cross-sectional survey was conducted among pastoralists in the Kiasar rangelands from the north of Iran; 65 pastoralists were selected from a total of 200 pastoralists of the area. Data were collected using interviews and questionnaires. The variables of risk taking and the tendency to have rangeland insurance was performed based on the logit regression method using nominal and ordinal logit models. The variables of age, main occupation of the pastoralists, existence of pasture out of season, compulsory livestock and rangeland insurance, education, and access to agents (P ≤ 0.05) were included in the model as factors affecting the level of risk taking of pastoralists in the study area. The existence of pasture out of season (with an estimated coefficient equal 3.04), livestock insurance (4.86), risk taking (0.25), and the age of herder (-0.09) were the most important variables (P ≤ 0.05) affecting the willingness of pastoralists for rangeland insurance. Structural changes should be made in the behavior of insurance companies to ensure more acceptance of rangeland insurance by pastoralists. Suggested changes include a variety of insurance coverage, proportionality, and fairness of premiums (according to the income of the pastoralists), timely payment of compensation, increased availability of out of season pastures. Structural changes in the behavior of insurance companies using promotional activities would improve and promote insurance in rangelands. In general, policies that increase income, awareness, and education of pastoralists are essential in enhancing the livelihood of pastoralists in the area.

Invasive plants are viewed as a universal threat to ranching enterprises because invasive plants can alter forage quantity or quality for livestock and therefore reduce net revenue. These concerns are almost entirely based on how invasive plants alter forage production in small plots rather than direct measures of invasive plant impacts on livestock production. In this study we quantify impacts of the invasive annual grass medusahead (Taeniatherum caput-medusahead [L.]) on livestock production on California annual rangeland and evaluate how management buffers or exacerbates impacts to net revenue. To do this, we tracked changes in yearling steer weights across the growing season (March to May) for 2 yr in eleven 2.1-ha pastures where medusahead abundance was experimentally manipulated. We then integrated weight gain results with market data to illustrate how changing grazing season duration and animal density in response to either a 10% increase or decrease in medusahead impacts net revenue. Holding grazing season duration and end-of-season residual forage constant across pastures, pastures with more medusahead supported a lower density of animals than pastures with less medusahead. However, this decrease in livestock production was significantly less than impacts reported from indirect estimates in the literature. Medusahead impacts on net revenue depend on livestock management decisions. Responding to a 10% increase in medusahead cover by shortening the grazing season reduced net revenue 102.97 USD per hectare, whereas responding to a 10% increase in medusahead cover by reducing animal density by selling animals early increased net revenue 2.71 USD per hectare. Our study shows that the impacts of medusahead on livestock production may be lower than those estimated from indirect measures of invasive plant impacts on livestock production and that relatively simple changes in livestock grazing management could further reduce how invasive plant impacts on livestock production scale to impacts on net revenue.

Shrubs seeded during rangeland restoration often fail to adequately establish. One factor differentiating successful and unsuccessful shrub seeding efforts is competition from grasses seeded with shrubs and weeds. Despite efforts to control these neighbors in experiments, their abundances often remained high, which suggests neighbors may have limited shrubs in much previous research. In the northern Great Plains, I evaluated seeded shrub survival and growth across a grass and weed biomass gradient. The treatment that held neighbor cover lowest provided the greatest shrub density and size, but density was low even in this treatment. Nevertheless, the data support previous studies indicating controlling neighbors can greatly benefit shrubs. Constraining neighbors increased shrub density ∼25 × (from about 0.005 to 0.13 m^-2). This large proportional effect could make the difference between shrub restoration success and failure when greater emergence occurs due to factors unrelated to competition, such as shrub seed rate and environmental conditions. Controlling neighbors is often necessary to establish shrubs, but currently, shrubs can fail to establish even where neighbors are well controlled. Additional research is needed to overcome barriers to establishment unrelated to competition.

Enteric methane (CH₄) emissions from livestock represent a significant agricultural source of greenhouse gas worldwide. The aim of this study was to determine the effect of plant species and season on nutritional value and methanogenic potential of Florida native rangelands. Treatments consisted of a 4 × 2 factorial arrangement of plant species (creeping bluestem [Schizachyrium scoparium var. stoloniferum {Nash} Wipff], lopsided Indiangrass [Sorghastrum secundum {Elliott} Nash], maidencane [Panicum hemitomon Schult.], and saw-palmetto [Serenoa repens {W. Bartram} Small]) and season (summer or autumn) distributed in a randomized complete block design with four replicates. Samples were analyzed for crude protein (CP), neutral detergent fiber, in-vitro CH₄ production, and in-situ ruminal digestibility. The greatest digestive matter (DM) effective degradability was observed in the summer for creeping bluestem (422 g kg-¹), followed by lopsided Indiangrass (379 g kg-¹), maidencane (380 g kg-¹), and saw-palmetto (250 g kg-¹). The DM effective degradability decreased from summer to autumn for all species, except saw-palmetto. Maidencane had the greatest CP effective degradability in the summer (491 g kg-¹), followed by lopsided Indiangrass (350 g kg-¹), creeping bluestem (279 g kg-¹), and saw-palmetto (170 g kg-¹); however, lopsided Indiangrass and maidencane decreased CP effective degradability from summer to autumn. There was no difference in CH₄ production among creeping lopsided Indiangrass and maidencane (mean of 7 mg g^-1 DM), and saw-palmetto had the least CH₄ emissions (2 mg g^-1 DM). Grazing lopsided Indiangrass and maidencane in the summer was an effective strategy to optimize the use of native plant species with greater nutrient digestibility than autumn. Management practices intended to increase rangeland productivity, and the proportion of native grass species relative to saw-palmetto are expected to increase CH₄ production. Further research is warranted to evaluate the impacts on rangeland management on animal performance and greenhouse gas balance.

Exotic annual grass invasion and dominance of sagebrush-bunchgrass steppe is a concern because it decreases biodiversity and promotes frequent wildfires. Management is needed to reduce exotic annual grasses to prevent sagebrush-bunchgrass communities from transitioning to annual grasslands. Grazing during the off season (fall-winter) has shown promise at reducing exotic annual grasses, but it has not been evaluated in plant communities dominated by sagebrush and native bunchgrasses. We compared moderate grazing during the off season with not grazing in five Wyoming big sagebrush (Artemisia tridentata ssp. wyomingensis [Beetle & A. Young] S.L. Welsh)-bunchgrass communities in the northern Great Basin. Treatments were applied annually for 10 yr (2009-2010 through 2018-2019). Plant community characteristics were measured after treatments had been applied from 6 to 10 yr. Off-season grazing reduced exotic annual grass density and cover. After a decade, annual grass cover was twofold greater in ungrazed areas. Sandberg bluegrass (Poa secunda J. Presl) density increased with off-season grazing, but large bunchgrass density was similar between off-season grazed and ungrazed areas. Perennial and annual forb density and cover were similar between off-season grazed and ungrazed treatments. Biological soil crust cover was also similar between off-season grazed and ungrazed areas. The results of this study provide strong evidence that off-season grazing has application for managing exotic annual grasses in sagebrush-bunchgrass steppe. Considering the vast scope of the exotic annual grass problem, properly applied grazing may be the most cost-efficient tool to mediate the impacts of annual grass invasion.

We analyzed the variation of plant composition, forage production, and livestock diet across a broad stocking rate gradient on Eastern Hills rangelands of Uruguay. Our approach encompassed five ranches subjected to mixed sheep-cattle grazing and combined field surveys, microhistological fecal analysis, and remote sensing techniques. We hypothesized that selectivity would decrease as stocking rate increased. Vegetation data and fecal samples were obtained in 17 paddocks in 2008. To investigate the role of stocking rate on vegetation, we focused on dominant species and forage type cover. Diet composition was analyzed at forage type level. Annual net primary productivity was estimated for each paddock using the normalized difference vegetation index derived from the MODIS (Moderate Resolution Imaging Spectroradiometer) sensor. We found a clear relationship between the variation in stocking rate and floristic and forage type composition, both suggesting a deterioration of grassland conservation status. Cool season grass cover varied from 25% to 5%, from low to high stocking rates. Dicot cover showed an opposite trend, with values around 15% in the low and moderate stocking levels and reaching 35% on high-stocked paddocks. Diet composition and diet overlap between herbivores also showed clear patterns of response to stocking rate. On the other hand, livestock selectivity interacted with herbivore type. While cattle showed the expected pattern, sheep did not decrease selectivity in winter as stocking rate increased. Contrary to expectations, annual net primary productivity was similar across the different stocking rate levels and the month of maximum productivity was generally March. Our study provides strong evidence of marked rangeland degradation; however, the lack of response in terms of ANPP and the ability of sheep to maintain selectivity under high stocking rates could help to explain the lack of responsiveness in the adoption of generalized stocking adjustments by the ranchers.

Mesic meadows provide valuable water and forage resources for wildlife and livestock in the arid western United States. Greater sage-grouse (Centrocercus urophasianus), a species of conservation concern, rely on these habitats because they support forb species of high importance to broods during late brood rearing. Because mesic meadows comprise a small fraction of the landscape, identifying grazing strategies compatible with maintenance and production of mesic resources is vital to balancing livestock production with suitable conditions for sage-grouse. We evaluated relationships between short-duration grazing treatments and habitat components important to sage-grouse in mesic meadows. In 2019 and 2020, we implemented short-duration (16 d) grazing treatments that varied by season (Early: early June; Late: early August) and intensity (control: 0%, moderate: 30-40%, high: 70-80% relative use). We evaluated cover and biomass percentages of high importance forbs (HIF), soil moisture, and noxious weed cover before and after grazing and again after pasture regrowth (Early: ≈13 wk, Late: ≈6 wk). Short-duration treatments did not reduce HIF cover or biomass. Early-season (P= 0.018) and high-intensity (P= 0.04) grazing increased HIF cover during the pregrazing sample period from 2019 to 2020, suggesting positive effects of these treatments on HIF cover during the pregrazing sample period. Postgrazing HIF cover and biomass percentages remained similar across treatments. Percentages of HIF biomass after regrowth were greater (P= 0.04) in early-season than late-season treatments in 2020. Seasonal declines in soil moisture from pregrazing to regrowth sample periods were greater (P < 0.001) in early-season treatments than late-season treatments but not associated with grazing intensity (P= 0.60). Cover of noxious weeds remained unchanged under short-duration treatments. Our study emphasizes the potential of early-season, high-intensity grazing to increase HIF cover and biomass for brood-rearing sage-grouse in mesic meadows over short time intervals.

Exotic annual grass invasion is a pressing concern in sagebrush rangelands of the western United States. Overgrazing and fire have historically both been implicated in the rise of annual grasses, but experiments that compare the effect of grazing versus fire are lacking, particularly for contemporary grazing practices such as off-season (fall and winter) grazing. We compared 1) burned and ungrazed (burned), 2) off-season, moderately grazed and unburned (grazed), and 3) ungrazed and unburned (control) treatments at five Wyoming big sagebrush (Artemisia tridentata ssp. wyomingensis [Beetle & A. Young] S.L. Welsh) sites in southeastern Oregon for half a decade. Fire, but not off-season grazing, substantially increased exotic annual grass cover and abundance. Vegetation cover and density were generally similar between grazed and control areas. In contrast, at the end of the study exotic annual grass cover and density were over fourfold greater in burned areas. Exotic annual grass became the dominant plant group in burned areas, but not in grazed and control areas. Cover and density of annual forbs, predominately non-native species, were generally greater in the burned compared with grazed and control treatments. Fire also decreased soil biological crust cover and sagebrush cover and density compared with grazed and control treatments. This study provides strong evidence that fire is a threat to the sustainability of Wyoming big sagebrush communities at risk of exotic annual grass dominance, but that off-season, moderate grazing poses little risk. However, considering the spatial extent of our study was limited, further evaluations are needed across a larger geographic area. Given that off-season grazing can decrease the probability of fire, off-season grazing may be a valuable tool to reduce the risk of exotic annual grass dominance.

Management-intensive grazing, which is proposed to increase forage and animal productivity and maintain soil integrity and biodiversity, is seen as an alternative to meet 21st century agricultural and environmental challenges. The purpose of this study was to test the hypothesis that high levels of trampling of standing vegetation associated with mob grazing (a.k.a., ultrahigh stocking density) leads to increased plant diversity and productivity. A long-term experiment was established on a subirrigated meadow in the Nebraska Sandhills as a complete block design comparing three grazing treatments applied annually during the growing season for 8 consecutive yr (2010-2017): 120-pasture rotation with one grazing cycle (mob; 225 000 kg live weight ha-¹), four-pasture rotation with one grazing cycle (4PR1; 7 000 kg live weight ha-¹), and four-pasture rotation with two grazing cycles (4PR2; 5 000 kg live weight ha-¹). All treatments were set at a moderate stocking rate (7.4 animal unit months ha-¹) using yearling steers. Percentage trampling, plant production, species composition, and steer weight gain were estimated annually. We applied linear mixed-effect models to account for year and treatment effect on the response variables. Percentage trampling on mob pastures ranged from 40% to 55% over the 8 yr of the study, nearly double that of the 4PR1 and 4PR2 pastures. We observed that mob grazing had no overall effect on plant species composition, aboveground production, and root growth relative to low stocking densities. Average daily gain of steers in the mob pastures was less than gain of steers in 4PR2 pastures in all years, with intermediate weight gains for the 4PR1 steers. Overall, stocking density did not appear to be a driver of plant composition and productivity in rotationally grazed pastures on subirrigated meadows in the Nebraska Sandhills.

Knowledge about feed intake and adequate nutritional status of dairy cows is important to achieve high milk yield in grazing systems. A possible, but subjective, method to estimate changes in grazing intake could be rumen fill scoring. Thus, a novel flow chart, based on existing criteria for rumen fill scoring was developed to simplify this approach.

The first objective of this study was to develop a flowchart to reduce training time for untrained observers and to support the observers in their decision-making process. Therefore, the quality of scoring of four trained observers that used the criteria, originally published by Zaaijer and Noordhuizen (2003), was assessed first. After that, the interobserver reliability of trained observers (control group) and untrained observers that used the novel flowchart was determined. The novel flowchart was tested twice. The second version of the flowchart included the feedback of the first round. To assess if rumen fill scoring is a suitable method for detecting changes in grazing intake was the second objective of this study. Therefore, it was investigated if rumen fill scores could be used to detect decreasing feed intake during a 6-d grazing period with limited feed allocation.

The experiments demonstrated that overall agreement between trained observers who used the criteria originally published was moderate (κF = 0.53). The overall agreement of untrained observers who used the novel flowchart increased from fair (κ_F = 0.40) to substantial (κ_F = 0.66) between the two versions of the flowchart. Finally, it was found that rumen fill scores decreased, according to decreasing feed allocation for this small sample. In conclusion, the novel flowchart simplified rumen fill scoring, thus facilitating the assessment of rumen fill as a potential method for estimating changes in pasture intake in research and practice.

Invasions of native plant communities by non-native species present major challenges for ecosystem management and conservation. Invasive annual grasses such as cheatgrass, medusahead, and ventenata are pervasive and continue to expand their distributions across imperiled sagebrush-steppe communities of the western United States. These invasive grasses alter native plant communities, ecosystem function, and fire regimes, threatening sagebrush ecosystem persistence. Spatial data describing the distribution and abundance of invasive species are often used by resource managers to identify, target, and determine needed interventions. However, there are challenges associated with translating these datasets into management actions. We conducted a review of available spatial products to assess advances in, and barriers to, applying contemporary model-based maps to support rangeland management. We found dozens of regional data products describing cheatgrass or annual herbaceous cover and few maps describing ventenata or medusahead. Over the past decade, IAG spatial data increased in spatial and temporal resolution and increasingly used response variables that indicate the severity of infestation such as percent cover. Despite improvements, use of such data is limited by the time required to find, compare, understand, and translate model-based maps into management strategy. There is also a need for products with higher spatial resolution and accuracy. In collaboration with a multipartner stakeholder group, we identified key considerations that guide selection of IAG spatial data products for use by land managers and other users. On the basis of these considerations, we discuss issues that contribute to a research-implementation gap between users and product developers and suggest future directions for improved development of management-ready spatial products.