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To examine the long-term productivity, profitability, and ecological interactions associated with whole farming systems, we established an interdisciplinary replicated comparison of a conventional and an experimental alternative crop-livestock farming system in southwest Virginia in 1988. The conventional system uses the best management practices commonly used in the mid-Atlantic region. The alternative system puts more emphasis on crop rotation, grazing and forage management, conservation tillage, cover crops, and integrated pest management. Each is managed as a year-round system, with management decisions based on the system's overall goals. The comparison is planned to run for 10 years, so that only preliminary conclusions can be drawn so far. These include the following: 1) similar total productivity can be achieved with either reduced or full use of herbicides and insecticides; 2) the need for N fertilization can be decreased using grazing management and short-rotation alfalfa; and 3) recycling of manure from cattle fed corn silage provides most nutrients needed for the following corn crop. The comparative profitability of the two systems has fluctuated among years, and it is too early to know which system is more profitable. The process of interdisciplinary systems research has increased our knowledge of total system interactions, challenged prior assumptions, and clarified the methodological problems of integrated systems research.
... The most well-known legume to improve nutrient cycling is alfalfa (Medicago sativa L.). Integrating alfalfa into crop rotations can reduce the need for synthetic N fertilizer (Luna et al. 1994;. In return, reduced fertilizer inputs decrease N leaching. ...
... Perennial grasslands are often grazed by ruminant animals. Grazing management can reduce the need for N fertilizer (Luna et al. 1994). ...
Current agricultural systems focused on production of few commodities are facing production, economic, and environmental challenges. To address these challenges, Integrated Crop Livestock Systems (ICLS) have emerged through three primary methods 1) perennial grasslands for grazing and/or hay production, 2) crop residue grazing, and 3) cover crop grazing. To evaluate potential of ICLS mitigating current challenges, a field scale model ICLS was developed in 2015. The ICLS includes 4-ha each of ‘Newell’ smooth bromegrass (Bromus inermis L.), ‘Liberty’ switchgrass (Panicum virgatum L.), and ‘Shawnee’ switchgrass. The ICLS also included 8-ha of continuous corn (Zea mays L.). In 2016, only hay was harvested from perennial grasslands and in 2017, 2018, and 2019 the perennial grasslands were grazed. Following grazing, the switchgrass varieties were harvested for residual biomass production post-senescence. Continuous corn included residue removal treatments with and without a cover crop. This thesis reports results from three studies. To evaluate the response of cool-season annual grass cover crops to defoliation, a greenhouse study, in conjunction with a replicated field experiment, was conducted in 2018-2019 and 2019-2020. Results showed small grains used as cover crops had decreased survivability and biomass production when defoliated during early plant establishment. Production data from the ICLS was used to construct enterprise budgets to evaluate system profitability on marginally productive cropland. The ICLS was not consistently more profitable than continuous corn production. However, baling hay only and removing grazing from the ICLS was more profitable than continuous corn production. To evaluate ICLS as a mitigation strategy for soil GHG emissions, soil N2O and CH4 were measured during each growing season in the perennial grasslands and continuous corn. Results suggested that 1) grazing perennial grasslands did not consistently impact soil GHG emissions, 2) crop residue and cover crop management may impact soil N2O emissions, and 3) continuous corn production resulted in greater soil N2O emissions than perennial grasslands due to higher application amounts of synthetic N fertilizer. The results from this research can provide options for producers implementing ICLS and insight for further development of ICLS for Eastern NE that meet production, economic, and environmental challenges. Advisors: Daren Redfearn and Rob Mitchell
... farmers and employees), has also long been identified (Davidson 1987). However, with such dynamic interactions, capture of robust data to provide definitive research outcomes often requires multi-year projects (Luna et al. 1994). ...
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Context. The aim of farm-systems research is to test concepts in a holistic context that enables results to be as applicable as possible to commercial farmers. A downside of such research has been that it can take severalseasonsto be confident in the consistency of the outcomes and interpretation of the results. Scientists are often reluctant to communicate outcomes until they have clear conclusions, which conflicts with farmers’ desire to see rapid answers and engage with research. Aims. This paper reviews a 3-year farm-systems research project investigating flexible milking strategies for New Zealand dairy farmers. The aims of this paper are to (1) examine the impact of real-time science communication in achieving farm system change, and (2) develop a framework for science communication and engagement in adaptive farm-systems research. Methods. The project involved farmerinterviews, a farmlet experiment, a component experiment, partnerfarms, modelling, and a farmer reference group. We use data from sources such as e-newsletter engagement, webinar participation, web-page engagement, presentation attendance, and farmer feedback to collect insights on the impact of the project. Key results. The analysis highlighted that farmers do not always seek complete information and will follow a project as it evolves, particularly when it is highly topical. We propose a framework for delivering adaptive farm systems research and communication. The framework includes the critical aspects for real-time farm-systems research: credible evidence, rapid results, inclusion of farmer voices, meaningful outcomes, flexible communication channels, iterative feedback loops, and adaptable research design. Conclusion. Farm-systems research can be designed to communicate results to farmers as a project develops, while simultaneously using the engagement with farmers to refine the direction of the research. Implications. This framework can guide scientists leading multi-year farm systems projects to design, implement, and communicate the project outcomes to improve farmer engagement and adoption.
... Recently, some US producers have adopted more diversified management systems that include crops and livestock 7,21 . However, operators of integrated production systems face immense challenges, including labor availability and allocation, timing of operations, equipment considerations, and supply and market availability 22 . Even with economic risks spread over multiple enterprises, producers with integrated operations still require information on potential benefits and trade-offs to manage their enterprises successfully. ...
International Atomic Energy Agency has published the technical report on Optimizing soil, water and nutrient use efficiency in integrated cropping–livestock production system in Southern India.
Livestock grazing systems are defined by multiple factors, including climate, soil, and forage resources, type of livestock enterprise(s), proximity to and timing of markets, and environmental concerns. This chapter deals with grazing strategies and systems, and focuses on grazing resources including types of grazed ecologic systems, forage‐livestock systems such as cow‐calf production, and integrated production systems. Grazed ecosystems include pastureland, cropland, forestland, and rangeland. Cow‐calf production depends heavily on grazed forage which uses lower productivity land sites. Forage systems are generally based on perennials, but can be augmented by grazing crop residues and others. Historically, integration of livestock and cropping farms characterized US and Canadian agriculture. Regions of specialization within ideal climates led to development of monocultures for crop production to maximize output and profitability.
The Centers for Disease Control and Prevention (CDC) estimates that financial losses from foodborne illnesses, including medical costs and losses in productivity, range from $500 million to $2.3 billion annually. Most studies have investigated only major and mostly known foodborne pathogen prevalence, such as Salmonella, Campylobacter, pathogenic E. coli, Shigella, Vibrio, and Listeria. In addition to bacterial pathogens and viruses, the risk of contamination of animal and plant food products with parasites exists. Parasites remain understudied because of the complexity of methods of isolation and identification. Therefore, minimizing the risks and enhancing intervention strategies to prevent cross-contamination of organic and conventional animal products and produce with parasites is a priority. A variety of advanced and rapid detection techniques for bacterial pathogens and parasites may be used as alternatives or in conjunction with culture methods. Detection of parasites in animal and plant food samples requires in vivo mice or any other susceptible and reliable model.
It was evaluated, by indicators, the sustainability of the Ranch Temascaltepec Universitary Center, that belongs to the Autonomous University of the Mexican State. Starting from the characterization and diagnosis, it was designed a proposal of sustainable management of the natural resources. For the installation, operation and evaluation of some components of this proposal, experiments were made for three years. These included the comparative evaluation of plots for forage production in monoculture and association, the islands of multipurpose trees and the lots of contention of erosion with vegetative techniques. The forage yields improved gradually during the period of evaluation, with higher quality for the forages associated. The different tree species showed divergent degrees of adaptation and development, due to the adverse conditions of the soil and climate. The vegetative techniques were efficacious to stop the accelerated erosive processes. The comparison of the final state of the system with the initial state shows significant improvements for the majority of the environmental and social indicators, although the profitability was negative due to the high cost of the installation of the components. It was proved that there is utility in the methodology, both for the design and operation of the proposal as well as for the evaluation of sustainability.
The sustainability of the university farm Temascaltepec belonging to the 'Universidad Autónoma del Estado de México' was evaluated through indicators. Based on the characterization and diagnosis, a proposal for natural resources sustainable management was designed. In order to install, operate and evaluate some components of this proposal, experiments for three years were realized, these included: the benchmarking in monoculture and association using lots for fodder production, for multipurpose trees, and for containing erosion with vegetative techniques. The forage yields gradually improved during the evaluation period, and forages association showed greater quality. The arboreal species showed divergent degrees of adaptation and development due to adverse ground and climate conditions. The vegetative techniques were effective to decrease the accelerated erosive processes. The comparison of the final state of the system with the initial state allows us to observe notable improvements for most of the environmental and social indicators, although the profitability was negative, due to the high cost of the components installation. The relevance of this methodology, for the design and operation of the proposal and for sustainability evaluation, was verified as much.
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Rye (Secale cereale L.), used as a winter cover crop, was killed by paraquat or by mowing with a bushog. In the early stages of subsequent no-till corn, abundance of armyworm, Pseudaletia unipuncta (Haworth), was lower in the mowed treatment compared with the sprayed treatment in three of five fields and did not differ in another field. Over the duration of the first armyworm generation, cumulative armyworm-days in the sprayed treatment were greater than in the mowed treatment in three of five fields and did not differ in another field. Mowing the cover crop was 40% less expensive than spraying. Competition from rye regrowth in the mowed treatment did not diminish yields. Corn silage yields were increased by mowing (P = 0.07), and the average increase in net benefit from mowing the cover crop compared with spraying was 91-113/ha. Cover crop mowing may be an economical and effective means of managing armyworm populations in no-till corn.
A sorghum-sudangrass hybrid [ Sorghum bicolor (L.) Moench. x Sorghum sudanense (P.) Stapf. ‘DEKALB SX17+’] (SSH) and foxtail millet [ Setaria italica (L.) Beauv.] (FM) were evaluated for their effects on weed populations when grown for forage and as land conditioners prior to late-summer, no-till planting of alfalfa ( Medicago sativa L. ‘Arc’). Both grasses established well in no-till situations, except for FM when excessive mulch impeded seed placement or seedling summer-annual weeds were not destroyed at planting time. SSH was the better competitor; after both were planted into a dense stand of seedling summer-annual weeds, SSH outyielded the weeds while FM did not. Both grasses suppressed weeds and enhanced subsequent alfalfa establishment. Obtaining adequate alfalfa stands was not a problem in no-till seedings: seedling populations often exceeded 300/m ² 3 to 6 weeks after planting. Lack of adequate weed control was associated with stand losses in which disease was also a factor. Biennial and perennial broadleaf species were the predominant weeds. Prior cropping of SSH or FM is a valuable option for growers wishing to establish alfalfa without tillage, particularly when summer forage is useful.
The western corn rootworm Diabrotica virgifera virgifera and northern corn rootworm D. barberi are the most serious insect pests of corn Zea mays in Canada and N-central USA. Management options are examined, with consideration of crop rotation, tillage and soil environment, planting and harvesting dates, host-plant resistance, and options for biological and insecticidal control. Particular attention is paid to integrated pest management which involves crop rotation, scouting fields to determine the need for control measures for silk clipping and root damage the following years, use of insecticides only when necessary, and consideration of environmental, biological, chemical and physical features that contribute to corn rootworm control. -P.J.Jarvis
Despite the widespread recognition that corn rootworms (northern, Diabrotica barberi Smith and Lawrence; and western, D. virgifera virgifera LeConte) can be controlled by crop rotation, there has been a persistent but erratic pattern of casual observations of damage to corn by rootworms in fields where corn is rotated annually with a nonhost crop. These reports are mainly from the northern cornbelt, and when the species involved has been identified, it has always been D. barberi. We observed 2 years of diapause in nearly half the eggs from adults collected from fields in three areas where corn is rotated annually. By contrast, only about 9% of the eggs were in diapause for 2 years when obtained from adults collected where corn is planted without rotation. Observations in 1985 of rootworm damage to corn in fields where the annual rotation of corn with a nonhost crop was modified by the “Payment in Kind” program in 1983 are explained most easily as due to the existence of prolonged diapause in the eggs. It appears that some populations of the northern corn rootworm may have adapted to crop rotation. This may be a case of an insect evolving an adaptation to a cultural practice.
The positive role of biological diversity in enhancing agricultural sustainability is presented in the context of crop rotation. Once common in virtually all farming systems, crop rotations have been simplified or eliminated during the past two decades from farming systems in most industrialized countries. Specialization, production intensification, government commodity programs, and the resulting short-term economic decisions have all had an influence in reducing crop rotation and diversity. Economic and environmental concerns have raised the question of agricultural sustainability in the public arena. We discuss here the role of diversity and crop rotation in relation to the sustainability issue, including matters of agronomic, economic, and environmental benefits, as well as increased efficiency in the use of fossil fuels. Constraints and future directions in the use of crop rotation in modern agriculture are described.
Year-round grazing systems for beef production from conception to slaughter
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