- Cover crops can increase ammonia volatilization and reduce the efficacy of urease inhibitors , SOIL SCIENCE SOCIETY OF AMERICA JOURNAL (2022)
- Distribution and Fractionation of Zinc and Copper in Poultry Litters Across North Carolina , COMMUNICATIONS IN SOIL SCIENCE AND PLANT ANALYSIS (2022)
- Legume cover crop type and termination method effects on labile soil carbon and nitrogen and aggregation , AGRONOMY JOURNAL (2022)
- Organic nitrogen fertilizer sources for field production of flue-cured tobacco (Nicotiana tabacum L.) , AGRONOMY JOURNAL (2022)
- Winter crop effect on soybean production in the Southeast United States , AGRONOMY JOURNAL (2022)
- Agronomic management of early maturing soybeans in North Carolina , CROP FORAGE & TURFGRASS MANAGEMENT (2021)
- Stover harvest and tillage effects on corn seedling emergence , AGRONOMY JOURNAL (2021)
- Understanding the Relationship Between Wireworm (Coleoptera: Elateridae) Damage, Varietal Resistance, and Cover Crop Use in Organic Sweetpotato , JOURNAL OF ECONOMIC ENTOMOLOGY (2021)
- Winter cover crop management in the production of organic flue-cured tobacco , AGRONOMY JOURNAL (2021)
- Ammonia volatilization, nitrous oxide emissions, and corn yields as influenced by nitrogen placement and enhanced efficiency fertilizers , Soil Science Society of America Journal (2020)
We will investigate the carryover effects of P fertilization on loblolly pine plantations and the effects on the soil microbial community.
On-farm trials will be used to measure mitigation of nitrous oxide and ammonia emissions from nitrogen fertilization of corn with and without the use of a urease and nitrification inhibitor. Control plots receiving zero N will be used to examine inherent soil health in the system and supply power relative to corn yields.
Cover crops are capable of mitigating many of the destabilizing factors influencing food and water security including climate change, pesticide resistance, depleted soils, competition among users for water, and decoupled nutrient cycles. Despite the myriad potential landscape-level benefits, cover crop adoption rates remain low. Cover crop use is a knowledge-intensive activity; farmers repeatedly cite management complexity and the lack of site- and system-specific information as barriers to adoption. This is further complicated by inconsistent management recommendations, and at times misinformation, resulting from a lack of coordination, communication, and awareness. Complex interactions in food production among intrinsic factors (climate and soil), management, and genetics exacerbate the issue. Social and political forces also add complexity via regulation and market forces. While there has been considerable research devoted to cover crops, there has been a failure to link impacts of climate, soil, genetics, and management decisions on cover crop performance. There is also a lack of transdisciplinarity and integration in research, education, and extension activities. We propose a transformation of US cropping systems through an information ecology to integrate cover crops and precision agriculture. An information ecology for precision sustainable agriculture would include, at minimum, open source software to reduce the cognitive overload of cover crop use by farmers; low cost hardware to crowdsource farm-scale data to inform cover crop research; and a knowledge commons for data sharing among transdisciplinary and cross-sector teams. An information ecology therefore has the potential to support long-term sustainability of US agricultural systems through the integration of cover crop research and practice.
Global climate change, food security challenges, environmental concerns, and global food crises are complex food system challenges that require innovative and interdisciplinary approaches to agricultural research and education. Increasing diversity creates a more productive and creative workforce with complex problem solving skills. Lack of focused recruitment and training programs in STEM has led to many groups being under-represented. Engaging diverse and multicultural undergraduates in hands-on, cutting-edge agriculture and food systems research while providing structured professional development training will increase student interest and ability to build careers in agriculture and food systems. Our overall project goal is to develop a summer-based agroecology research and experiential training program that addresses the challenges of sustainable agriculture production and incorporates professional career development and structured mentorship. We will recruit 30 students, 10 students per year for 3 years with at least 50% women and at least 40% from traditionally underrepresented groups, including underrepresented ethnicities, first generation college students, and economically disadvantaged groups, to participate in the 10-week paid summer training program. Specific program elements of the summer training program include: Hands-on research experience and training in four core themes that align with AFRI priority areas including: Sustainable crop production and technology; Soil health; Natural resources and the environment; and Food system and socio-economic impacts Integrated extension training through participation in relevant field days and workshops, as well as the development of resource materials for Cooperative Extension Individualized professional skills development, including writing, understanding agriculture career pathways, leadership training, diversity, equity and inclusion competencies and development of an e-portfolio Structured mentorship and network opportunities with faculty, graduate students and agricultural professionals The intellectual merit of this REEU, Diverse Agroecology and Sustainability Scholars Training Program, lies in developing a new and critically needed pipeline for the next generation of diverse sustainable agriculture professionals and researchers equipped to address our complex food and agriculture challenges. With the long-standing collaborative working team of multidisciplinary researchers and educators in agroecology and robust stakeholder partnerships within the Center for Environmental Farming Systems (CEFS), Cooperative Extension and various organizations associated with North Carolina State University (NC State), our project team has the experience and resources to ensure a quick start and successful implementation of the program. Assessment of participant knowledge, skills, and abilities will take place before, during, and after the research appointments to evaluate the level of achievement of program objectives and student learning outcomes.
Agricultural soils in the southeastern U.S., marked by high rainfall and warm temperatures, are often characterized with low organic C and soil pH. Organic farming relies on organic inputs and fundamentally alters the sources and forms of reactive carbon (C) and nitrogen (N) inputs. It also induces changes in soil physical and geochemical properties that may profoundly affect the abundances, composition and activities of soil microbes, including nitrifiers (i.e., ammonia-oxidizing bacteria and archaea) and diverse types of denitrifiers. However, there is still a lack of a holistic picture of organic farming effects on N-cycling microbes and their activities. We hypothesize that organic farming, if properly adopted, may induce consistent and predictable changes to foster the development of microbial communities for N retention and mitigation of N2O emissions. We plan to test our three specific hypotheses on long-term (19-yr) cropping systems at the Center for Environmental Farming Systems (Goldsboro, NC) as well as on multiple organic farms across North Carolina. Three major questions will guide our proposed research: 1) To what extent are these differences driven by long-term shifts in the microbial community? 2) What are the primary drivers and/or environmental factors that affect the composition and activities of nitrogen-cycling microbes? 3) To what extent are these differences driven by the quality and quantity of fertilizer inputs? Answering these questions will advance understanding of N transformations in organic systems and facilitate development of management regimes that enhance N use efficiency and ecosystem N retention, while reducing N2O emissions.ÃƒÂ¢Ã¢â€šÂ¬Ã¢â‚¬Å¡ÃƒÂ¢Ã¢â€šÂ¬Ã¢â‚¬Å¡ÃƒÂ¢Ã¢â€šÂ¬Ã¢â‚¬Å¡ÃƒÂ¢Ã¢â€šÂ¬Ã¢â‚¬Å¡ÃƒÂ¢Ã¢â€šÂ¬Ã¢â‚¬Å¡ÃƒÂ¢Ã¢â€šÂ¬Ã¢â‚¬Å¡ÃƒÂ¢Ã¢â€šÂ¬Ã¢â‚¬Å¡
Weed management was identified as a high priority of organic sweetpotato producers who lack chemical control options available to conventional producers. This project will examine the effectiveness of multiple weed management techniques including 1) the use of advanced sweetpotato lines and cultivars with bunching shoot architecture to outcompete weeds for light resources and allow for more efficient use of between-row cultivation, 2) modified planting density to reduce the critical period for weed removal, 3) identification of weed suppressive (allelopathic) lines that can function in a production environment, and 4) utilization of fall-planted cover crops and reduced tillage transplanting operations to reduce the dependence on cultivation. Recognizing that these techniques may have non-target effects, this project will also investigate the insect pest pressure and plant disease occurrences in the test plots. Research-based findings will be shared with stakeholders and the greater scientific community via field days, production meetings, expos, conferences, peer-reviewed journal publications, Extension publications/fact sheets/bulletins, and electronic newsletters, webpages, and social media. Throughout the proposed project, investigators will remain engaged with the US Sweetpotato Stakeholder Advisory Panel to ensure the project remains aligned with industry goals and that meaningful results are effectively communicated to stakeholders nation-wide. Identifying best practices for weed management, in an integrated pest management context, will facilitate the development and improvement of organic sweetpotato production, in line with Goal 1 of the Organic Agriculture Research and Extension Initiative.
The proposed project will use a chronosequence technique to evaluate changes in soil carbon storage and soil health indicators that occur over a 20 yr period from transition from conventional to organic management. Soil samples will be taken from on-farm sites that have been in organic management for a range of time and ensure and event distribution from year 0 to year 20. Soils from nearby abandoned or re-forested sites will be used as the regions maximum potential carbon accrual, while sites in year 0 or 1 of transition will be the theoretical starting point for carbon stock buildup. In addition to the on-farm trials, two intensive field experiments will be established at research stations on the coastal plains. These experiments will focus on carbon stock accrual within the first 3 years of transition from conventional to organic. Treatments will fall along a spectrum on management intensity, ranging from high intensity carbon building with organic amendments to business as usual production systems. This complementary study will allow inferences to be made around if active soil carbon building during transition can push the system further in the chronoseqenece and derive the potential benefits of increased soil health.
New injection bars available through Zoske, Bazooka-Farmstar, and Dietrich allow for manure injection into standing corn. Initial results out of Ohio and Minnesota indicate corn can withstand injection below the V5 growth stage without injury. The potential to utilize in-season injection could drastically increase the application window of swine sludge in a corn rotation, allowing the grower/applicator to get in the field when field conditions are optimum, especially in rainy springs such as we saw in 2020. However, there is little information on this injection system in the sandy soils of the Coastal Plain. Therefore, we propose small scale field testing to identify the impact of swine sludge injection on corn yield and quality.
The use of best management practices allow some soybean fields in NC to yield 70 bu/A or more, double the historical statewide average yield of 35 bu/A. Due to intensive management, usually these fields present adequate levels of soil nutrients and subsequently, the official recommendations of fertilizers for NC soils point to small or null rates of fertilizers, regardless of yield expectations. In an ongoing project sponsored by the NC Soybean Producers Association, we are refining the recommendations of P and K for high-yielding soybeans. In this proposal, we aim to field test supplemental fertilization strategies, at planting (starter N, S, and P) and during reproductive stages (N and micronutrients). The supplemental fertilization strategies will be compared with the standard fertilization program recommended by NCDA&CS using an economic analysis. We will perform this research in eight site-years, four sites in 2021 and four sites in 2022. We will measure yield, soil nutrient levels, nutrient uptake, and nutrient exported in the grain. We are requesting financial support to partially fund salaries (technician and hourly labor), field supplies, travel costs, and, soil and plant analysis associated with the project.
There is limited information available on the amount of nitrogen mineralized from previous manure applications in soils of North Carolina. To determine whether inorganic nitrogen applications to corn could be reduced in fields with a long history of manure application, a state-wide assessment will be conducted to determine the contribution of soil nitrogen to corn production in these situations. Extension Agents will identify farm fields for these nitrogen rate trials, which will be conducted in the Coastal Plain, Piedmont, and Tidewater regions of the state. The fields must have a history of manure application and a rotation that includes corn. Field strips will receive 30 lbs of starter N fertilizer per acre, and the strips will be split into five plots. Plots will receive varying rates of fertilizer (0, 50, 100, 150, and 200 lbs N/ac) at V4-V6 growth stage. Prior to sidedress N application, soil samples will be collected to determine the amount of inorganic nitrogen present in the soil. Grain yield will be measured, and the data collected will provide guidance on whether a pre-sidedress nitrate test could be utilized in manured soils in North Carolina, which could increase the efficiency of nitrogen use for North Carolina corn growers.