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

Virginia’s pasturelands are dominated by tall fescue (Schedonorus arundinaceus (Schreb.) Dumort., nom. cons. [Poaceae]), a competitive, non-native grass. Tall fescue has limited value for wildlife and insect pollinators, and it can pose issues for livestock if infected with an endophyte that produces a toxic alkaloid. Potential exists for developing more biodiverse pasturelands that would help reduce problems associated with tall fescue while increasing ecosystem services associated with improved wildlife and pollinator habitat. Native warmseason grasses (NWSG) and wildflowers (WF) have potential forage and conservation benefits; however, more research is needed to determine effective strategies that land managers can use to establish these species. This article summarizes 4 field experiments designed to evaluate establishment methods for NWSG and WF in tall fescue pasturelands. Experiments were established from 2016 to 2020 in central and western Virginia. Three evaluated preemergent imazapic herbicide applications while the fourth evaluated other methods, including glyphosate application, glyphosate combined with raking, prescribed fire, and tillage, to establish NWSG and WF. In the 3 experiments evaluating imazapic applications, the herbicide consistently suppressed wildflowers, with the exception of Rudbeckia hirta L. (Asteraceae), Desmanthus illinoensis (Michx.) MacMill. ex B.L. Rob. & Fernald (Fabaceae), Coreopsis lanceolata L. (Asteraceae), and Leucanthemum vulgare Lam. (Asteraceae). In the fourth experiment, tillage was the most effective method to establish wildflowers. Overall, we found imazapic can improve NWSG establishment, but suppresses most WF species tested in this environment. Methods to achieve more consistent WF establishment are needed if adoption of more biodiverse pasturelands becomes a future management goal.

Reliable measures of biomass, species composition, nitrogen status, and nutritive value provide important indicators of the status of pastures and rangelands, allowing managers to make informed decisions. Traditional methods of sample collection necessitate significant investments in time and labor. Proximal sensing technologies have the potential to collect more data with a smaller investment in time and labor. However, methods and protocols for conducting pasture assessments with proximal sensors are still in development, equipment and software vary considerably, and the accuracy and utility of these assessments differ between methods and sites. This review summarizes the methods currently being developed to assess pastures and rangelands worldwide and discusses these emerging technologies in the context of diffusion of innovation theory.

Reliable measures of biomass, species composition, nitrogen status, and nutritive value provide important indicators of the status of pastures and rangelands, allowing managers to make informed decisions. Traditional methods of sample collection necessitate significant investments in time and labor. Proximal sensing technologies have the potential to collect more data with a smaller investment in time and labor. However, methods and protocols for conducting pasture assessments with proximal sensors are still in development, equipment and software vary considerably, and the accuracy and utility of these assessments differ between methods and sites. This review summarizes the methods currently being developed to assess pastures and rangelands worldwide and discusses these emerging technologies in the context of diffusion of innovation theory.

Effective management of dairy farms requires an accurate prediction of pasture biomass. Generally, estimation of pasture biomass requires site-specific data, or often perfect world assumptions to model prediction systems when field measurements or other sensory inputs are unavailable. However, for small enterprises, regular measurements of site-specific data are often inconceivable. In this study, we approach the estimation of pasture biomass by predicting sward heights across the field. A convolution based sequential architecture is proposed for pasture height predictions using deep learning. We develop a process to create synthetic datasets that simulate the evolution of pasture growth over a period of 30 years. The deep learning based pasture prediction model (DeepPaSTL) is trained on this dataset while learning the spatiotemporal characteristics of pasture growth. The architecture purely learns from the trends in pasture growth through available spatial measurements and is agnostic to any site-specific data, or climatic conditions, such as temperature, precipitation, or soil condition. Our model performs within a 12% error margin even during the periods with the largest pasture growth dynamics. The study demonstrates the potential scalability of the architecture to predict any pasture size through a quantization approach during prediction. Results suggest that the DeepPaSTL model represents a useful tool for predicting pasture growth both for short and long horizon predictions, even with missing or irregular historical measurements.

Mob stocking is a type of livestock management method where high densities of animals are restricted to a small area of grassland for short periods of time (e.g., 12–24 hr.) before being moved to new forage. Use of mob stocking has generated considerable interest among forage-livestock professionals in recent years, but questions remain about its purported benefits to cattle and forage plants. To address questions about the possible benefits of mob stocking, a 3-yr study (2014–2016) was conducted in Virginia, USA comparing mob, rotational, and continuous stocking methods in a temperate grassland common to that region. The main objective of this study was to evaluate how mob-stocking management affected selected forage variables, cattle performance, and legume/weed abundance. Herbage mass and nutritive value were measured monthly. Cow and calf weights and body condition score (BCS) were used as indicators of animal performance. Legumes (red and white clover) were over-seeded prior to the study, and their abundance along with weeds were evaluated annually thereafter. Mean herbage mass and forage nutritive values were similar across mob, rotational and continuously stocked systems despite extra-long rest periods that allowed grasses to grow tall and over-mature under mob stocking. Cow weights going into winter were lower (P < 0.05) under mob stocking (619 kg) compared with continuous stocking (688 kg) possibly because many tall grasses were trampled and not grazed. Lastly, we found mob stocking can favor establishment of erect-growing red clover (Trifolium pretense L.), but it had no effect on weed abundance. Overall, we found few compelling reasons why mob stocking should be adopted for season-long forage and livestock production over other stocking methods in this environment.

The integration of trees into pasture systems can have variable effects on forage and animal growth. Some reports of these systems have indicated that animal gains are similar or better even when tree presence lowers forage yield. Forage production and animal performance were compared in black walnut (Juglans nigra L.)-based and honeylocust (Gleditisia triacanthose L.)-based silvopasture systems and open pastures in a randomized complete block design with three blocks over three summers. Cool season-based, mixed grass pastures were rotationally stocked with four to seven lambs depending on available forage. A rising plate meter was used to estimate pre- and post-graze forage mass. Forage samples of the mixed sward were collected and analyzed for nitrogen (N) and neutral detergent fiber (NDF) concentrations. Species percent cover was estimated using a modified Daubenmire approach at the same 12 points within each experimental unit every 4 wk during the study. Pre-graze herbage mass was similar (P = 0.0717) in honeylocust silvopastures (5020 ± 30 kg·ha⁻¹) and open pastures (4930 ± 30 kg·ha⁻¹) and lowest (P < 0.0001) in the black walnut silvopastures (3560 ± 30 kg·ha⁻¹). Forages in the black walnut and honeylocust silvopastures had similar (P = 0.4867) N concentrations (23.3 ± 0.4 and 23.9 ± 0.4 g·kg⁻¹, respectively), which was greater (P ≤ 0.0003) than that of the forages in the open pastures (21.0 ± 0.4 g·kg⁻¹). Forages in the honeylocust silvopasture had lower (P ≤ 0.0042) NDF concentrations (507 ± 3 g·kg⁻¹) than forages in the black walnut silvopasture and open pastures (mean = 525 ± 3 g·kg⁻¹). Forage species present in the black walnut silvopastures differed from those present in the open and honeylocust systems, which had similar composition. Despite differences in stocking rates, total lamb weight gains per system did not differ (P ≥ 0.7592) among black walnut, honeylocust, and open pasture systems (10 ± 2, 12 ± 2, and 10 ± 2 kg·d⁻¹, respectively). Silvopasture

Integrating trees into pastures, a practice known as silvopasture, may benefit livestock in the summertime through the provision of shade. The purpose of this project was to compare the behavioral patterns of sheep grazing in silvopastures and open pastures. Black walnut (Juglans nigra L.) and honeylocust (Gleditisia triacanothose L.) based silvopasture systems were compared with open pastures in a randomized complete block design with three blocks over two summers. Behavior measures were recorded within a replicate within a week, and these measures were taken sequentially within three experimental periods. Ewe lambs (n = 3) within each experimental unit were equipped with a wideband audio-recording device to detect prehension events. Time-lapse cameras documented sheep behavior every 60 s. In the silvopastures, the lambs spent over 90% of daylight hours within shade from trees. Lambs in silvopastures spent more time lying down than animals in the open pastures (P ≤ 0.01), while lambs in the open pastures spent more than 2 h longer each day standing (P < 0.0001). Lambs in the black walnut silvopastures spent more time grazing (488 ± 14 min · d⁻¹) than lambs in the honeylocust silvopastures (438 ± 14 min · d⁻¹; P = 0.0493) and lambs in the open pastures (417 ± 14 min · d⁻¹; P = 0.0026). There was no difference in grazing time for lambs in the latter two systems (P = 0.5597). Spectral analysis of the imagery revealed that the lambs in the black walnut silvopastures grazed more frequently than the lambs in the other systems for both years. The acoustic analysis, though limited by recorder durability to 47 complete recordings, revealed no difference in total bites taken per day (P ≥ 0.7222) or in the morning (P ≥ 0.2069), afternoon (P ≥ 0.5816), and evening periods (P ≥ 0.9337). Silvopastures provide an opportunity to improve lamb comfort in the summer.

Integrating trees into pastures, a practice known as silvopasture, may benefit livestock in the summertime through the provision of shade. The purpose of this project was to compare the behavioral patterns of sheep grazing in silvopastures and open pastures. Black walnut (Juglans nigra L.) and honeylocust (Gleditisia triacanothose L.) based silvopasture systems were compared with open pastures in a randomized complete block design with three blocks over two summers. Behavior measures were recorded within a replicate within a week, and these measures were taken sequentially within three experimental periods. Ewe lambs (n = 3) within each experimental unit were equipped with a wideband audio-recording device to detect prehension events. Time-lapse cameras documented sheep behavior every 60 s. In the silvopastures, the lambs spent over 90% of daylight hours within shade from trees. Lambs in silvopastures spent more time lying down than animals in the open pastures (P ≤ 0.01), while lambs in the open pastures spent more than 2 h longer each day standing (P < 0.0001). Lambs in the black walnut silvopastures spent more time grazing (488 ± 14 min · d⁻¹) than lambs in the honeylocust silvopastures (438 ± 14 min · d⁻¹; P = 0.0493) and lambs in the open pastures (417 ± 14 min · d⁻¹; P = 0.0026). There was no difference in grazing time for lambs in the latter two systems (P = 0.5597). Spectral analysis of the imagery revealed that the lambs in the black walnut silvopastures grazed more frequently than the lambs in the other systems for both years. The acoustic analysis, though limited by recorder durability to 47 complete recordings, revealed no difference in total bites taken per day (P ≥ 0.7222) or in the morning (P ≥ 0.2069), afternoon (P ≥ 0.5816), and evening periods (P ≥ 0.9337). Silvopastures provide an opportunity to improve lamb comfort in the summer.

The world population is exponentially growing and is expected to reach over 9 billion people by 2050. In order to feed the growing population, producers will have to rely on new technologies to increase yields. Globally there is focus on global warming and pollution that can damage ecosystems. A way to solve both of these conundrums is through understanding of nutrient cycles and the implementation of precision agriculture techniques to create a nutrient management system that meets the needs of the plants, but yet prevents unnecessary losses from the cycles. Studies show promise in the implementation of precision agriculture systems, with increased yields and better nutrient use efficiencies. However, studies show that there is variation between plots and areas, proving that more studies need to be conducted to determine the impact of precision agriculture on nutrient management.

Discusses proper fertilizing and liming of forage crops in Virginia

Compares using poultry litter and commercial fertilizers, with choices based on price of nutrients, their availability, and spreader limitations.

Hay and pastureland in the United States typically consists of introduced cool-season grass species. Many of these cool-season grasses are used due to their productivity, palatability, and tolerance of heavy grazing and aggressive hay harvesting. Biological characteristics of cool-season grasses make them less productive in the summer, potentially limiting cattle production. Native warm-season grasses use a different chemical pathway for photosynthesis than cool-season grasses allowing for them to have higher photosynthetic potential in the summer when temperatures are warmer. This literature review investigates the integration of native warm-season grasses in hay and pasture systems and the potential ecosystem services they may generate. Relevant, available research on native warm-season grasses and potential ecosystem service benefits in forage and livestock systems was reviewed and summarized by type of ecosystem service provided. Ecosystem service provisions were then compared to those of cool-season alternatives to determine the potential gains of native warm-season grass integration. Based on available literature, native warm-season grasses have the potential to be an integral part of future forage livestock agroecosystems in the United States due to the likelihood for overall productivity and environmental benefits.