@article{hackman_cook_strahm_carter_woodley_garcia_albaugh_rubilar_campoe_2024, title={<i>Pinus</i><i> taeda</i> carryover phosphorus availability on the lower Atlantic Coastal Plain}, volume={555}, ISSN={["1872-7042"]}, DOI={10.1016/j.foreco.2024.121701}, abstractNote={Phosphorus (P) fertilizer that remains in the soil after harvest and into the subsequent rotation is referred to as carryover P. Carryover P is not well understood in loblolly pine (P. taeda) silviculture, especially on highly P responsive sites, where this effect could potentially have the greatest benefit to land managers. Our study aims to determine the duration of the P carryover effect and the magnitude of response to soil P as it relates to previously applied P fertilizer rates from the previous rotation. To address this knowledge gap, we studied two highly weathered sites on the lower Atlantic coastal plain: a somewhat poorly drained Spodosol and a poorly drained Alfisol over three years from pre- to post-harvest. Two years post planting, carryover fertilizer treatments resulted in a 13% increase in height for the 121 kg P ha-1, a 15% for the 81 kg P ha-1, and a 17% increase for the fertilized 40 + 45 kg P ha-1 treatments compared to the control for the Alfisol. Spodosols appeared to respond to any additional fertilization compared to the control group regardless of rate. Importantly, we found that O horizon mass and P content from the first rotation, approximately seven years before harvest, exhibited a positive linear relationship with one-year-old heights in the Spodosol and one- and two-year-old heights in the Alfisol. These findings shed light on the importance of the O horizon characteristics and its potential as an indicator for tree growth in subsequent rotations.}, journal={FOREST ECOLOGY AND MANAGEMENT}, publisher={Elsevier BV}, author={Hackman, Jacob and Cook, Rachel and Strahm, Brian and Carter, David and Woodley, Alex and Garcia, Kevin and Albaugh, Timothy and Rubilar, Rafael and Campoe, Otavio}, year={2024}, month={Mar} }
 @article{halker_woodley_reberg-horton_inoa_suchoff_2024, title={Evaluating Chinese fiber hemp (<i>Cannabis sativa</i> L.) varieties and planting dates in North Carolina}, volume={7}, ISSN={["2639-6696"]}, url={https://doi.org/10.1002/agg2.20569}, DOI={10.1002/agg2.20569}, abstractNote={Abstract Field trials were conducted in 2021 and 2022 to evaluate the effects of planting date (mid‐March, mid‐April, and mid‐May) on 11 fiber hemp ( Cannabis sativa L. <0.3% total tetrahydrocannabinol) varieties. Trials were conducted in Goldsboro, Kinston, and Salisbury, NC. Each location followed a split‐plot randomized complete block design with at least three blocks where planting date was the main‐plot and variety the sub‐plot. Varieties investigated originated from China and Australia (2021 only). Data collection included flowering time, end of season stand counts, stem height, diameter, and final retted dry straw yield. We found differences among the varieties investigated in both years; however, no distinct trend was observed across years. All varieties investigated flowered at the end of August and beginning of September, allowing for a long growing season and ability to produce abundant biomass. In general, the Chinese genetics yielded higher stem biomass compared to previously reported European genetics. Stem thickness was >7.5 mm, which is generally considered the maximum width for textile‐grade fiber production. To achieve thinner stems from the varieties investigated, harvesting prior to male‐flower initiation may be required. The crop experienced temperatures below freezing in both years with no signs of damage. Taken together, farmers seeking to plant fiber hemp in North Carolina have a wide planting window from mid‐March to mid‐May using these Chinese varieties.}, number={3}, journal={AGROSYSTEMS GEOSCIENCES & ENVIRONMENT}, author={Halker, China Allissa P. and Woodley, Alex L. and Reberg-Horton, S. Chris and Inoa, Shannon Henriquez and Suchoff, David H.}, year={2024}, month={Sep} }
 @article{forfora_azuaje_vivas_vera_brito_venditti_kelley_tu_woodley_gonzalez_2024, title={Evaluating biomass sustainability: Why below-ground carbon sequestration matters}, volume={439}, ISSN={["1879-1786"]}, url={https://doi.org/10.1016/j.jclepro.2024.140677}, DOI={10.1016/j.jclepro.2024.140677}, abstractNote={Biomass, as a raw material, has been identified as a crucial component of decarbonization strategies to mitigate climate change. Decisions on which biomass should be targeted for different purposes are dependent on variables such as availability, chemical composition, and sustainability. Consumer perception often positions non-wood sources, such as bamboo, as environmentally preferable feedstocks for fiber-based product production. Yet, this perceived environmental benefit lacks robust scientific substantiation and standardized methodologies. This study addresses this gap by conducting a cradle-to-gate life cycle assessment (LCA) of twelve biomass production systems encompassing tree plantations, dedicated crops, and agricultural residues for energy and bioproducts manufacture. The evaluated feedstocks include southern softwood, wheat straw, rice straw, rice husk, hemp hurd, sugarcane bagasse, switchgrass, biomass sorghum (United States), eucalyptus (Brazil), bamboo (China), and northern softwood (Canada). Incorporating a critical yet often overlooked factor, this LCA integrates the potential soil organic carbon sequestration (SOC) via below-ground biomass for each biomass type. This consideration significantly alters the estimated carbon intensity per ton of feedstock, potentially reshaping sustainability perceptions as certain systems emerge as carbon sinks. From a cradle-to-farm gate perspective, the assessed global warming potential for biomass production spans 12–245 kg CO2eq per oven-dry ton (ODt), factoring only anthropogenic emissions. However, when accounting for SOC sequestration, the range shifts to −170 to 228 kg CO2eq per ODt, highlighting potential the role of biomass to act as carbon sink systems. By illuminating the dynamic influence of SOC sequestration, this study contributes to a more comprehensive understanding of biomass-related carbon emissions, shedding light on pathways to mitigate environmental impact.}, journal={JOURNAL OF CLEANER PRODUCTION}, author={Forfora, Naycari and Azuaje, Ivana and Vivas, Keren A. and Vera, Ramon E. and Brito, Amelys and Venditti, Richard and Kelley, Stephen and Tu, Qingshi and Woodley, Alex and Gonzalez, Ronalds}, year={2024}, month={Feb} }
 @article{hackman_woodley_carter_strahm_averill_vilgalys_garcia_cook_2024, title={Fungal biomass and ectomycorrhizal community assessment of phosphorus responsive <i>Pinus taeda</i> plantations}, volume={5}, ISSN={["2673-6128"]}, DOI={10.3389/ffunb.2024.1401427}, abstractNote={Ectomycorrhizal fungi and non-ectomycorrhizal fungi are responsive to changes in environmental and nutrient availabilities. Although many species of ectomycorrhizas are known to enhance the uptake of phosphorus and other nutrients for Pinus taeda , it is not understood how to optimize these communities to have tangible effects on plantation silviculture and P use efficiency. The first step of this process is the identification of native fungi present in the system that are associated with P. taeda and influence P uptake efficiency. We used sand-filled mesh bags baited with finely ground apatite to sample ectomycorrhizal and non-ectomycorrhizal fungi associated with the rhizosphere of P-responsive P. taeda under several field conditions. Mesh bags were assessed for biomass accumulation over three years using a single three-month burial period pre-harvest and three six-month burial periods post-planting. Amplicon sequencing assessed ectomycorrhizal and non-ectomycorrhizal communities between phosphorus treatments, sites, mesh bags, and the rhizosphere of actively growing P. taeda in the field. We found biomass accumulation within the mesh bags was inversely related to increasing phosphorus fertilization (carryover) rates from pre-harvest to post-planting. Up to 25% increases in total biomass within the bags were observed for bags baited with P. Taxonomic richness was highest in Alfisol soils treated with phosphorus from the previous rotation and lowest in the Spodosol regardless of phosphorus treatment.}, journal={FRONTIERS IN FUNGAL BIOLOGY}, author={Hackman, Jacob and Woodley, Alex and Carter, David and Strahm, Brian and Averill, Collin and Vilgalys, Rytas and Garcia, Kevin and Cook, Rachel}, year={2024}, month={May} }
 @article{lay-walters_heagy_woodley_hoffmann_2024, title={Impact of Pre-Plant Fertilizer Rates in Combination with Polysulphate® on Soil Nitrogen Distribution and Yield of Short-Day Strawberries (<i>Fragaria</i> x <i>ananassa</i> cv. Camarosa)}, volume={14}, ISSN={["2073-4395"]}, url={https://www.mdpi.com/2073-4395/14/4/774}, DOI={10.3390/agronomy14040774}, abstractNote={Strawberries are by far the most produced soft fruit (blueberries, raspberries, blackberries, and strawberries) worldwide, with China and the US being the two countries with the most production. In the US, strawberries reached a farm gate value of more than USD 3 billion in 2023 and are predominantly grown in the open field on an annual cycle in hilled-up soil beds using plastic mulch (plasticulture). This process relies on adequate pre-plant fertilizer application for plant establishment and fruit development. In North Carolina (US), it is current practice to apply pre-plant fertilizer containing 67 nitrogen (N) kg/ha; however, with increasing fertilizer costs and environmental concerns, questions remain as to whether or not pre-plant full-spectrum fertilizer rates can be reduced and substituted with organic low-N fertilizer sources, such as Polysulphate, without impacting yield or fruit quality. For this reason, field trials were established to evaluate the impact of pre-plant fertilizer rates on strawberry production (‘Camarosa’). Trials were conducted in the 2019–2020 and 2020–2021 seasons at two locations in North Carolina. The following N-rate pre-plant fertilizer treatments were applied: 80.1, 67.3, 54.1, 41.1, 33.6, 28.0, and 0 kg/ha. NO3 and NH4 content were frequently assessed in each replicate in the raised bed profile between planting and spring fertilizer application. Marketable and total strawberry yields were assessed over 6 weeks in the spring of 2020 and 2021. Our trial results showed that, especially in sandy soil, N rapidly declined under plastic within the first 8 weeks after pre-plant fertilizer application. However, no impact between pre-plant fertilizer rates and plant yield was observed. Treatments that contained Polysulphate and lower amounts of full-spectrum fertilizer showed significantly lower N concentrations in the soil while maintaining similar yields and fruit quality compared to grower-standard pre-plant fertilizer treatments. In summary, our results show that it is possible to reduce N content in pre-plant fertilizer by up to 50% compared to current recommendations without causing yield loss in short-day strawberry cultivars.}, number={4}, journal={AGRONOMY-BASEL}, author={Lay-Walters, Amanda and Heagy, Kimberly and Woodley, Alex and Hoffmann, Mark}, year={2024}, month={Apr} }
 @article{qiu_zhang_zhang_xu_zhao_bai_zhao_wang_sheng_bloszies_et al._2024, title={Intermediate soil acidification induces highest nitrous oxide emissions}, volume={15}, ISSN={["2041-1723"]}, DOI={10.1038/s41467-024-46931-3}, abstractNote={Abstract Global potent greenhouse gas nitrous oxide (N 2 O) emissions from soil are accelerating, with increases in the proportion of reactive nitrogen emitted as N 2 O, i.e., N 2 O emission factor (EF). Yet, the primary controls and underlying mechanisms of EFs remain unresolved. Based on two independent but complementary global syntheses, and three field studies determining effects of acidity on N 2 O EFs and soil denitrifying microorganisms, we show that soil pH predominantly controls N 2 O EFs and emissions by affecting the denitrifier community composition. Analysis of 5438 paired data points of N 2 O emission fluxes revealed a hump-shaped relationship between soil pH and EFs, with the highest EFs occurring in moderately acidic soils that favored N 2 O-producing over N 2 O-consuming microorganisms, and induced high N 2 O emissions. Our results illustrate that soil pH has a unimodal relationship with soil denitrifiers and EFs, and the net N 2 O emission depends on both the N 2 O/(N 2 O + N 2 ) ratio and overall denitrification rate. These findings can inform strategies to predict and mitigate soil N 2 O emissions under future nitrogen input scenarios.}, number={1}, journal={NATURE COMMUNICATIONS}, author={Qiu, Yunpeng and Zhang, Yi and Zhang, Kangcheng and Xu, Xinyu and Zhao, Yunfeng and Bai, Tongshuo and Zhao, Yexin and Wang, Hao and Sheng, Xiongjie and Bloszies, Sean and et al.}, year={2024}, month={Mar} }
 @article{gillespie_sit_loucanides_hu_matusko_terwilliger_shi_steffen_woodley_hu_2024, title={Multi-amplicon nitrogen cycling gene standard: An innovative approach for quantifying N-transforming soil microbes in terrestrial ecosystems}, volume={195}, ISSN={["1879-3428"]}, url={https://doi.org/10.1016/j.soilbio.2024.109461}, DOI={10.1016/j.soilbio.2024.109461}, journal={SOIL BIOLOGY & BIOCHEMISTRY}, author={Gillespie, Christopher J. and Sit, Tim L. and Loucanides, Althea J. and Hu, Jialin and Matusko, Brooke E. and Terwilliger, Nicholas R. and Shi, Wei and Steffen, Samantha M. and Woodley, Alex L. and Hu, Shuijin}, year={2024}, month={Aug} }
 @article{huddell_thapa_marcillo_abendroth_ackroyd_armstrong_asmita_bagavathiannan_balkcom_basche_et al._2024, title={US cereal rye winter cover crop growth database}, volume={11}, ISSN={["2052-4463"]}, DOI={10.1038/s41597-024-02996-9}, abstractNote={AbstractWinter cover crop performance metrics (i.e., vegetative biomass quantity and quality) affect ecosystem services provisions, but they vary widely due to differences in agronomic practices, soil properties, and climate. Cereal rye (Secale cereale) is the most common winter cover crop in the United States due to its winter hardiness, low seed cost, and high biomass production. We compiled data on cereal rye winter cover crop performance metrics, agronomic practices, and soil properties across the eastern half of the United States. The dataset includes a total of 5,695 cereal rye biomass observations across 208 site-years between 2001–2022 and encompasses a wide range of agronomic, soils, and climate conditions. Cereal rye biomass values had a mean of 3,428 kg ha−1, a median of 2,458 kg ha−1, and a standard deviation of 3,163 kg ha−1. The data can be used for empirical analyses, to calibrate, validate, and evaluate process-based models, and to develop decision support tools for management and policy decisions.}, number={1}, journal={SCIENTIFIC DATA}, author={Huddell, Alexandra M. and Thapa, Resham and Marcillo, Guillermo S. and Abendroth, Lori J. and Ackroyd, Victoria J. and Armstrong, Shalamar D. and Asmita, Gautam and Bagavathiannan, Muthukumar V. and Balkcom, Kipling S. and Basche, Andrea and et al.}, year={2024}, month={Feb} }
 @article{hackman_cook_strahm_carter_woodley_garcia_2024, title={Using microdialysis to assess soil diffusive P and translocated sap flow P concentrations in Southern <i>Pinus taeda</i> plantations}, volume={1}, ISSN={["1573-5036"]}, DOI={10.1007/s11104-023-06468-8}, journal={PLANT AND SOIL}, author={Hackman, Jacob and Cook, Rachel and Strahm, Brian and Carter, David and Woodley, Alex and Garcia, Kevin}, year={2024}, month={Jan} }
 @article{woodard_schultheis_jennings_woodley_suchoff_2024, title={Horizontal Planting Orientation Can Improve Yield in Organically Grown Sweetpotato}, volume={59}, ISSN={["2327-9834"]}, DOI={10.21273/HORTSCI17352-23}, abstractNote={Sweetpotato [Ipomoea batatas (L.) Lam.] is one of North Carolina’s (USA) most important organic commodity crops; however, yields tend to be less when compared with conventionally produced sweetpotato. Standard field establishment uses unrooted stem cuttings that are transplanted vertically in the soil. Producers in other countries typically use other planting orientations, including cuttings transplanted horizontally. Empirical evidence from North Carolina, USA, sweetpotato producers suggests that a horizontal orientation may improve yields. An organically managed field study using ‘Monaco’ sweetpotato was conducted in 2020 and 2021 in Bailey, NC, USA. The study evaluated stem cutting planting orientations (vertical, sleeve, horizontal), stem cutting length (25 cm and 38 cm), and harvest time (early or late) in a full-factorial randomized complete block design. In 2020, marketable yields were 16% greater for the horizontal orientation compared with the vertical orientation, with intermediate yields using the sleeve attachment. However, in 2021, there were no differences in marketable yield among planting orientations. In both years, US No. 1–grade yields were significantly greater when cuttings were planted horizontally compared with vertically, with an average increase of 18%. Delaying harvest until ∼126 days is recommended to increase yields for ‘Monaco’, regardless of planting orientation. This study provides evidence that a horizontal planting orientation could increase premium root yields and improve land-use efficiency for organically produced sweetpotatoes.}, number={1}, journal={HORTSCIENCE}, author={Woodard, Alyssa J. and Schultheis, Jonathan R. and Jennings, Katherine M. and Woodley, Alex L. and Suchoff, David H.}, year={2024}, month={Jan}, pages={36–42} }
 @article{mathers_heitman_huseth_locke_osmond_woodley_2023, title={No-till imparts yield stability and greater cumulative yield under variable weather conditions in the southeastern USA piedmont}, volume={292}, ISSN={0378-4290}, url={http://dx.doi.org/10.1016/j.fcr.2023.108811}, DOI={10.1016/j.fcr.2023.108811}, abstractNote={With projected increases in global temperatures and changes in regional climate, understanding the impact of soil management choices on yield stability is critical for farmer decision-making and agricultural resiliency. No-till and conservation tillage have had variable yield effects depending on crop and location, requiring long-term system-specific studies to gauge potential benefits. Yield and weather data from a 28-year tillage study in the southeastern U.S. piedmont region were analyzed to determine the effect of various conservation tillage practices on maize and soybean productivity and stability under a variety of growth conditions. Growing seasons were grouped by soil moisture and temperature during crop growth stages, and mean crop yields and yield coefficient of variation for the tillage treatments were calculated within the year clusters. Probability density estimates were also used to predict the likelihood of obtaining yields at low and high percentiles. No-till and conservation tillage increased maize yields 42–93% and no-till decreased coefficient of variation of maize yields when soil moisture was low by 10–32%, but had a less pronounced effect on soybean yields. However, the probability of reaching the 90th yield percentile was greater in no-till than conventional tillage in both maize and soybean, by 15% and 10%, respectively. Yield differentiation occurred early in the study, before there was likely substantial differentiation of soil properties from tillage treatments. Previous reports from the site have likewise indicated little differentiation in soil health between tillage systems over the life of the study. Results suggest that surface residue management may be an important driver of system performance, possibly more so than overall soil health.}, journal={Field Crops Research}, publisher={Elsevier BV}, author={Mathers, Cara and Heitman, Joshua and Huseth, Anders and Locke, Anna and Osmond, Deanna and Woodley, Alexander}, year={2023}, month={Mar}, pages={108811} }
 @article{kulesza_burns_woodley_gatiboni_shupe_hicks_2022, title={Distribution and Fractionation of Zinc and Copper in Poultry Litters Across North Carolina}, volume={5}, ISSN={["1532-2416"]}, DOI={10.1080/00103624.2022.2072866}, abstractNote={ABSTRACT Zinc (Zn) and copper (Cu) are necessary micronutrients for crop production. However, excess Zn and Cu applied through land application of manures can result in Zn and Cu toxicity, reducing yields. With many integrators and little information on the formulation of poultry feeds in North Carolina (NC), it is difficult to predict the fractionation of Zn and Cu in litters generated at facilities, as the form of Zn and Cu determines mobility and bioavailability. Therefore, statewide data from the NC Department of Agriculture and Consumer Services was analyzed to determine regional variation of total Zn and Cu. The results showed a significant effect of the region on the total Zn and Cu among the three production regions in the state. Additionally, 11 broilers and broiler breeder litter samples were analyzed to determine the distribution of Zn and Cu in acid soluble, reducible, oxidizable, and residual fractions. Total Zn and Cu averaged 675 mg/kg and 629 mg/kg, respectively. There was a significant interaction between the region and Zn concentration in the fractions. However, there was no region interaction when converted to a percentage of the sum of the fractions, indicating Zn partitions similarly across a wide range of concentrations and 37%, 40%, 21%, and 0.6% was found in the acid soluble, reducible, oxidizable, and residual fractions, respectively. Region did not have an effect on Cu fractionation, with 26%, 8%, 67%, and 2% of Cu in the acid-soluble, reducible, oxidizable, and residual fractions, respectively. Results indicate greater bioavailability and mobility potential for Zn as compared to Cu.}, journal={COMMUNICATIONS IN SOIL SCIENCE AND PLANT ANALYSIS}, author={Kulesza, Stephanie and Burns, Joseph and Woodley, Alex and Gatiboni, Luciano and Shupe, Maggie and Hicks, Kristin}, year={2022}, month={May} }
 @article{burns_kulesza_vann_woodley_2022, title={Effects of Nitrogen Source and Rate on Soybean Yield and Quality}, volume={9}, ISSN={["1532-2416"]}, url={https://doi.org/10.1080/00103624.2022.2118299}, DOI={10.1080/00103624.2022.2118299}, abstractNote={ABSTRACT The poultry industry in North Carolina (NC) has increased substantially over the past few decades, which has led to widespread availability of poultry litter. While many grain producers in NC utilize litter in their fertilization programs, it is typically applied to the corn or wheat crops that are in the rotation with soybean, instead of directly prior to soybeans. However, there is interest in application to soybean. Therefore, three field sites were established across NC in both 2019 and 2020, with four replicates of 11 treatments: four litter rates (22.4, 44.8, 89.7 and 134.5 Mg/hectare), six inorganic nitrogen (N) fertilizer rates (16.8, 33.6, 67.3, 134.5, 201.8, and 269.0 kg N/hectare), and a control. The impact of these treatments on biomass production, tissue N, plant population, yield, and grain quality were investigated. There was no significant effect on yield in 2019; however, there was a significant effect on yield in 2020, showing a negative correlation with inorganic N fertilizer in Plymouth and a 22% reduction in yield over the range of inorganic N treatments. It is possible there was an increased salt effect in these plots, as there was a negative response in plant population at five of six site years. While there was a positive correlation between grain protein and increasing inorganic N rate, growers are not paid based on grain quality. The results of this study suggest N application at planting is not beneficial for growers, but litter could be applied to meet soybean phosphorus or potassium demands.}, journal={COMMUNICATIONS IN SOIL SCIENCE AND PLANT ANALYSIS}, author={Burns, Joseph and Kulesza, Stephanie and Vann, Rachel and Woodley, Alex}, year={2022}, month={Sep} }
 @article{machanoff_vann_woodley_suchoff_2022, title={Evaluation of conservation tillage practices in the production of organic flue-cured tobacco}, volume={5}, ISSN={["2639-6696"]}, url={https://doi.org/10.1002/agg2.20317}, DOI={10.1002/agg2.20317}, abstractNote={AbstractIntensive tillage in flue‐cured tobacco (Nicotiana tabacum L.) contributes to soil erosion and reduced water‐holding capacity of soils. Conservation tillage minimizes soil disturbance by planting a crop directly into the residue of overwintered cover crop. Reducing tillage has been shown to improve soil health (increased rainwater infiltration, improved water‐holding capacity, reduced erosion) and to reduce production costs (fuel and labor). The objective of this study was to compare the effects of conservation and conventional tillage on weed management in organically grown flue‐cured tobacco. Field studies were conducted in Kinston, NC, in 2019 and 2020 and in Rocky Mount, NC, in 2020, comparing the impacts of conventional tillage and conservation tillage on weed emergence and tobacco production. An overwintered cereal rye (Secale cereal L.) cover crop was conventionally tilled or terminated via roller‐crimper and left in place as a mulch prior to transplant of flue‐cured tobacco. Cover crop biomass, weed emergence and biomass, soil resistance, crop yield and quality, and cured leaf chemistry were evaluated. In all environments, conservation tillage with cover crop residue reduced weed density and biomass when compared with conventional tillage treatments. In 2019, cured leaf yield was higher under conservation tillage practices than under conventional tillage. In 2020, environmental conditions in both locations resulted in crop loss. These results indicate that conservation tillage practices may be an effective weed management strategy while improving yields in an organic production system. However, organic flue‐cured tobacco grown under conservation tillage is vulnerable to extreme rain events due to the exclusion of in‐season cultivation.}, number={4}, journal={AGROSYSTEMS GEOSCIENCES & ENVIRONMENT}, author={Machanoff, Cordelia H. and Vann, Matthew Christopher and Woodley, Alex L. and Suchoff, David}, year={2022} }
 @article{hackman_ozyhar_chien_hilty_woodley_cook_2022, title={Evaluation of synthetic hydroxyapatite as a potential phosphorus fertilizer for application in Forest plantations}, volume={18}, ISSN={["2158-0715"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85136474133&partnerID=MN8TOARS}, DOI={10.1080/21580103.2022.2115149}, abstractNote={Abstract Synthetic hydroxyapatite (HA) was compared against triple superphosphate (TSP) and two unprocessed phosphate rocks (PR1, PR2) to (1) quantify and assess a synthetic lamellar structured-HA for its solubility and diffusiveness under acidic, sandy, soil conditions, (2) Evaluate synthetic lamellar structured-HA as a phosphorus early rotation fertilizer for Eucalyptus saplings. Soil incubation experiments verified that HA released more diffusive phosphorus into the soil than non-synthetic phosphate rock and had similar amounts of diffusive phosphorus as TSP. The solubility of HA at pH 3 and pH 6 was higher than that of raw ground phosphate rocks (apatites). Total dry-matter yield (DMY) and shoot-length of Eucalyptus seedlings grown for 154 days in acid soil (pH 4.9) were increased significantly by the application of HA compared to the control, PR2, and mixed (HA + PR2). The lack of a DMY response using TSP indicates that phosphorus may not have been the limiting factor. However, considering TSP and HA had similar solubilities and released diffusive phosphorus at similar levels, the only variable we failed to control for was the CaCO3 provided by the HA and not the TSP. Further experimentation is needed to confirm this hypothesis. Overall, HA is a promising candidate to supplement traditional phosphorus fertilizers for acidic sandy Eucalyptus silviculture.}, number={3}, journal={FOREST SCIENCE AND TECHNOLOGY}, author={Hackman, Jacob and Ozyhar, Tomasz and Chien, S. H. and Hilty, Florentine and Woodley, Alex and Cook, Rachel L.}, year={2022}, month={Jul}, pages={127–134} }
 @article{machanoff_vann_woodley_suchoff_2022, title={Evaluation of the use of polyethylene mulches in the production of organic flue-cured tobacco}, volume={7}, ISSN={["1435-0645"]}, url={https://doi.org/10.1002/agj2.21100}, DOI={10.1002/agj2.21100}, abstractNote={AbstractWeed and insect pest management in organic flue‐cured tobacco (Nicotiana tabacum L.) is challenging due to lack of effective and affordable approved control options. Polyethylene plastic mulches are used in vegetable and berry production to manage in‐row weed populations, buffer soil temperatures, limit rain‐induced soil loss, and maintain soil moisture. Mulch color can affect plant growth, soil temperature, and insect pest populations in vegetable crops. Field trials were conducted in Kinston, NC, in 2019 and 2020 and Whiteville, NC, in 2020. Red, white, black, and silver polyethylene mulch (with drip irrigation) and bare ground with and without drip irrigation were compared to evaluate effects on tobacco yield, quality, and pests. Tobacco yields were elevated by at least 290% in mulch treatments compared with bare ground with irrigation in 2020 (p < .05), but did not differ in 2019 due to precipitation and temperature differences that conveyed an increased benefit in 2020. Opaque mulches successfully suppressed weed emergence. Fewer aphids were present in highly reflective silver mulch than all other treatments with irrigation in both years. Black and red mulch warmed soils while silver cooled them, affecting nitrogen mineralization rates. Higher levels of plant available nitrogen were maintained in mulch treatments, but tobacco nitrate levels and overall quality were not affected. These results are consistent with plasticulture research in other crops. The factors that make plasticulture well suited to intensively managed, high value crop production may benefit organic flue‐cured tobacco production especially when grown in rotation with other intensively managed crops.}, journal={AGRONOMY JOURNAL}, author={Machanoff, Cordelia A. and Vann, Matthew Christopher and Woodley, Alex L. and Suchoff, David}, year={2022}, month={Jul} }
 @article{bloszies_reberg-horton_heitman_woodley_grossman_hu_2022, title={Legume cover crop type and termination method effects on labile soil carbon and nitrogen and aggregation}, volume={114}, ISSN={["1435-0645"]}, url={https://doi.org/10.1002/agj2.21022}, DOI={10.1002/agj2.21022}, abstractNote={AbstractGrowers use cover crops to provide nutrients for crops and build soil organic matter (SOM). Termination methods may alter the effects of cover crops on soil labile C and N. We examined how two cover crops and three termination methods affected soil microbes, soil aggregates, and C and N pools in an organic grain system. We compared crimson clover (Trifolium incarnatum L.) (CC), hairy vetch (Vicia villosa Roth) (HV), and a control together with disking, mowing, or a roller‐crimper for effects on hot‐water‐extractable carbohydrates, microbial biomass carbon (MBC) and microbial biomass nitrogen (MBN), potentially mineralizable C and N, and aggregation (quantified by mean weight diameter [MWD]). Disking comprised flail mowing plots and then cultivating. Roller‐crimping occurred via a roller with blades. Vetch soil contained 14% higher MBC than no cover crop pretermination, possibly because of enhanced rhizodeposition. Planting CC resulted in 44% higher MBC than no cover crop a week after termination, likely due to its higher biomass C/N ratio. Disking decreased MWD relative to flail mowing in no cover crop soils at 4 wk after termination across both years at 0‐to‐5‐cm depth. In addition, MWD was lower under CC than under no cover crop for both the flail mowed and roller‐crimped treatments at 4 wk after termination across both years from 0 to 5 cm. This is possibly due to enhanced desiccation of the soil in bare plots after termination. Our results indicate that quantity and quality of biomass of different legume species, rather than termination methods, dominated effects on labile C.}, number={3}, journal={AGRONOMY JOURNAL}, publisher={Wiley}, author={Bloszies, Sean A. and Reberg-Horton, S. Chris and Heitman, Joshua L. and Woodley, Alex L. and Grossman, Julie M. and Hu, Shuijin}, year={2022}, month={Apr} }
 @article{kulesza_manning_vann_suchoff_woodley_mcginnis_2022, title={Organic nitrogen fertilizer sources for field production of flue-cured tobacco (Nicotiana tabacum L.)}, volume={2}, ISSN={["1435-0645"]}, url={https://doi.org/10.1002/agj2.20989}, DOI={10.1002/agj2.20989}, abstractNote={AbstractDespite rapid expansion of organic tobacco (Nicotiana tabacum L.) production in the US, limited research has been conducted comparing the numerous organic fertilizer sources. Organic flue‐cured tobacco traditionally relies on feather meal as the organic N fertility source, as it is readily available, but there is limited information on alternative organic N fertilizers. The objective of this research was to investigate seven different organic fertilizer sources to determine their effect on the growth and development of flue‐cured tobacco. From 2018 to 2019, field sites were established at four locations in North Carolina. Fertilizer treatments included sodium nitrate, composted layer manure, feather meal, corn gluten, soy protein, blood meal, and seabird guano. Both years, these organic N treatments were banded at sidedress (10 d after transplanting) at a rate of 78 kg total N ha−1. Sodium nitrate resulted in higher foliar nitrate‐N concentration than composted layer manure at layby and higher cured leaf yield compared with feather meal and composted layer manure. However, soy protein and seabird guano were often similar to sodium nitrate in yield response and resulted in higher yields when compared with other sources of organic N, such as feather meal and composted layer manure. While feather meal and composted layer manure resulted in a 10 and 11% reduction in yield, respectively, there was no significant difference in tobacco value among treatments. Our results suggest that organic tobacco farmers have other options for N selection beyond the current feather meal standard.}, journal={AGRONOMY JOURNAL}, publisher={Wiley}, author={Kulesza, Stephanie B. and Manning, Nicholas J. and Vann, Matthew C. and Suchoff, David H. and Woodley, Alexander L. and McGinnis, Michelle M.}, year={2022}, month={Feb} }
 @article{gross_vann_brown_formella_gibbs_gurganus_heiniger_hurry_jordan_leary_et al._2021, title={Agronomic management of early maturing soybeans in North Carolina}, volume={9}, ISSN={["2374-3832"]}, DOI={10.1002/cft2.20122}, abstractNote={AbstractInterest in producing indeterminate, early maturing soybean [Glycine max (L.) Merr.] varieties [maturity group (MG) ≤IV] has increased in the southeastern United States as producers seek ways to increase soybean yields. The objective of this experiment was to generate agronomic management recommendations for early maturing soybean varieties across the southeastern United States and compare these management recommendations to historical recommendations for later‐maturing varieties through identification of the optimal seeding rates, row spacing, planting dates, and fertility management. Experiments were conducted across North Carolina at seven environments in 2018 and at four environments in 2019. Two MGs were used in this study: MG III and MG IV. Data on soybean yield and soybean seed quality were collected. Row spacing recommendations were similar to recommendations for later‐maturing varieties with narrow rows providing a 7.3 bu acre–1 yield advantage across environments on average, with more pronounced yield advantages in high‐yield environments. Seeding rate impacted soybean yield but not seed quality. An economic analysis was conducted for seeding rate, suggesting that 80,000 to 120,000 seeds per acre will optimize both profit and yield across environments with May planting. Planting date sometimes impacted yield and seed quality, suggesting that earlier planting with these varieties could be critical to optimizing soybean yield and seed quality. Fertility applications at R1 (beginning of flowering) did not have an impact on soybean yield or seed quality.}, journal={CROP FORAGE & TURFGRASS MANAGEMENT}, author={Gross, MaKayla Raquel and Vann, Rachel and Brown, Austin and Formella, Adam and Gibbs, Andrea and Gurganus, Rod and Heiniger, Ryan and Hurry, Jarette and Jordan, David and Leary, Matthew and et al.}, year={2021}, month={Sep} }
 @article{kulesza_woodley_heather_kilroy_2022, place={111 RIVER ST, HOBOKEN 07030-5774, NJ USA}, title={Cover crops can increase ammonia volatilization and reduce the efficacy of urease inhibitors}, volume={1}, ISSN={["1435-0661"]}, url={https://doi.org/10.1002/saj2.20367}, DOI={10.1002/saj2.20367}, abstractNote={AbstractSurface application of urea can result in high nitrogen (N) losses through ammonia (NH3) volatilization. While management practices aim to increase the efficiency of nutrient cycling and prevent N loss, it is unknown whether the combination of multiple practices will have a synergistic or antagonistic effect. Therefore, laboratory volatilization studies were conducted to determine the effect of five cover crop treatments (surface clover [Trifolium incarnatum L.] and rye [Secale cereale L.], incorporated clover and rye, and bare soil), three N application timings (2, 4, and 8 wk after cover crop addition), and two N sources (untreated and treated urea) on the effectiveness of a urease inhibitor. Soils were incubated according to N application timing treatment, amended with the appropriate N source, and placed in chambers which captured NH3 over 7 d. There were significant interactions between cover crop treatment and N source and N source and N application timing on cumulative NH3 loss, ranging from 29 to 174 kg N ha−1. Losses were highest from treated urea when applied 2 wk after residue addition (75.9 kg N ha−1) or on top of surface residues (85.8 kg N ha−1). There was no significant effect of application timing on cumulative NH3 loss from untreated urea. However, inhibitor effectiveness did increase when residue was applied eight weeks after residue addition (77%) as compared with 2 wk after residue addition (45%). Future research should focus on alternate dosing or application timing to overcome high residue scenarios in these systems.}, number={2}, journal={SOIL SCIENCE SOCIETY OF AMERICA JOURNAL}, publisher={Wiley}, author={Kulesza, Stephanie B. and Woodley, Alex L. and Heather, Kayleigh and Kilroy, Grace}, year={2022}, month={Jan} }
 @article{agomoh_drury_reynolds_woodley_yang_phillips_rehmann_2021, title={Stover harvest and tillage effects on corn seedling emergence}, volume={113}, ISSN={["1435-0645"]}, url={https://doi.org/10.1002/agj2.20738}, DOI={10.1002/agj2.20738}, abstractNote={AbstractCorn (Zea mays L.) stover is an increasingly important feedstock for biofuel and bioproduct production; however, excessive harvest of corn stover from agricultural fields may affect corn seedling emergence and subsequent plant population which may reduce corn growth and yield. Field experiments were conducted over four consecutive growing seasons in southwestern Ontario to determine under continuous corn cropping system the effects of no‐tillage (NT), conventional tillage (CT), and five rates of stover harvest (0, 25, 50, 75, and 100 wt. %) on corn seedling emergence in a Harrow sandy loam and in a Brookston clay loam. Time to achieve 50% seedling emergence (t0.5), emergence rate constant (kG), and final seedling population (MG) were adequately simulated using the Gompertz function. Irrespective of stover removal rate and soil type, t0.5 was 2 d longer, and kG was 32% lower, under NT compared to CT. In Harrow sandy loam, stover removal from NT reduced t0.5 in 1 out of 4 yr. The 100% removal reduced t0.5 relative to 0, 25, 50, and 75% removal by 1.1–2.2 d in 2015. Averaged across both tillages and all removal rates, kG was greater in Harrow sandy loam than in Brookston clay loam. Stover removal rates had no effect on MG but averaged over all removal rates and soil types, MG was 9% lower for NT compared to CT in 2016. No‐tillage practice under corn production can impede seedlings emergence early in the growing season and stover removal from the field can help mitigate against this effect.}, number={4}, journal={AGRONOMY JOURNAL}, publisher={Wiley}, author={Agomoh, Ikechukwu V. and Drury, Craig F. and Reynolds, W. Daniel and Woodley, Alex and Yang, Xueming and Phillips, Lori A. and Rehmann, Lars}, year={2021}, month={Jul} }
 @article{pellegrino_woodley_huseth_2021, title={Understanding the Relationship Between Wireworm (Coleoptera: Elateridae) Damage, Varietal Resistance, and Cover Crop Use in Organic Sweetpotato}, volume={114}, ISSN={0022-0493 1938-291X}, url={http://dx.doi.org/10.1093/jee/toab118}, DOI={10.1093/jee/toab118}, abstractNote={Abstract
               North Carolina is the largest producer of sweetpotato (Ipomoea batatus L.) in the United States but only a small percentage of total production is organic. Transition to organic sweetpotato production has been limited, in part due to a lack of effective non-chemical strategies to control wireworms (Coleoptera: Elateridae). To help bridge this knowledge gap, this study focused on documenting the relationship between wireworm damage to sweetpotato roots and the use of cover crops, a common way to maintain soil health in organic production. This study also tested a wireworm-resistant variety (Monaco) against the widely cultivated susceptible variety (Covington). Two different field studies were used to test the interaction between cover crops and insect-resistant sweetpotato varieties. We first examined a reduced-till cover crop system where cover crop residue remained on the soil surface when transplanting sweetpotato. The following year, we tested a fully incorporated cover crop system with spring termination and intensive tillage before sweetpotato transplanting. To complement these field studies, a greenhouse experiment was conducted to compare the efficacy of the wireworm-resistant variety with two susceptible sweetpotato varieties. Results show that varietal resistance had a strong effect on the amount of wireworm damage observed, with susceptible sweetpotato having more direct wireworm damage than the resistant variety. The effect of the cover crop was not found to be significant in any trial. This study provides important context about the role of varietal resistance in organic production and relatively low risk of cover crop use.}, number={5}, journal={Journal of Economic Entomology}, publisher={Oxford University Press (OUP)}, author={Pellegrino, Alyssa M and Woodley, Alex L and Huseth, Anders S}, editor={Munyaneza, JosephEditor}, year={2021}, month={Sep}, pages={2127–2134} }
 @article{hahn_woodley_vann_2021, title={Winter cover crop management in the production of organic flue-cured tobacco}, volume={113}, ISSN={["1435-0645"]}, url={https://doi.org/10.1002/agj2.20656}, DOI={10.1002/agj2.20656}, abstractNote={AbstractLegume cover crops are not traditionally used in tobacco (Nicotiana tabacum L.) production due to concerns related to unpredictability of N supply and extended mineralization affecting quality of cured tobacco leaf. This study was conducted to determine if cover cropping with legumes could mitigate organic N fertilizer investment in tobacco without compromising yield, value, or quality. In 2018 and 2019, three winter cover crops: hairy vetch (Vicia villosa Roth) (HV); Austrian winter pea (Pisum sativum var. arvense L.) (AWP); and crimson clover (Trifolium incarnatum L.) (CC), were compared to a no‐cover crop control with typical organic N management in Rocky Mount and Kinston, NC. This study found no significant negative effects (α = .05) from legume cover cropping on yield or value of tobacco. In addition, AWP and HV increased yields between 13 and 37% compared to the no‐cover control. Value (US$ ha−1) did not differ from the control in 2018 or 2019 at any location, except at Kinston, where HV increased value 44% in 2019. In‐season soil samples suggest that HV provided N to tobacco up to flowering, however this did not negatively impact quality, yield, or value. Our research did not support grower concerns of prolonged N availability and found evidence that legume cover crops may allow for partial reduction in applied N without compromising the value of the product.}, number={3}, journal={AGRONOMY JOURNAL}, publisher={Wiley}, author={Hahn, Samuel. L. and Woodley, Alex. L. and Vann, Matthew. C.}, year={2021}, month={May} }
 @article{gross_vann_woodley_jordan_2022, title={Winter crop effect on soybean production in the Southeast United States}, volume={114}, ISSN={["1435-0645"]}, url={https://doi.org/10.1002/agj2.20950}, DOI={10.1002/agj2.20950}, abstractNote={AbstractVarious winter crops can be produced before soybean [Glycine max (L.) Merr] in the Southeast United States, however the effect of these winter crops on soybean productivity and the optimum maturity group to use following various winter crops remains unknown. This experiment was conducted in five environments across North Carolina in 2019 and 2020 to understand the effect of winter crop and soybean maturity group (MG) on soybean productivity. Winter crops investigated included cereal rye (Secale cereale L.) as cover crop, cereal rye–crimson clover (Trifolium incarnatum L.) as cover crop mixture, May fallow, wheat (Triticum aestivum L.) for grain, rapeseed (Brassica napus L.) for grain, and June fallow. Three soybean cultivars (MGs III, V, and VII) were evaluated following each winter crop. Data collected were cover crop/residue biomass, winter crop grain yields, soybean stand, soil moisture, soil temperature, soybean chlorophyll content, and soybean yield. Across environments, winter crop did not affect soybean yield despite differences in soybean stand, soil moisture, soil temperature, and soybean chlorophyll content following various winter crops. The results indicate that across the environments evaluated in this experiment, factors such as soybean stand, soil moisture, or N availability were not limiting factors for soybean productivity and that soybean yield response is relatively insensitive to previous crops. Across winter crops, greater yields typically were achieved with a MGs V and VII cultivar than with a MG III cultivar. Results from this experiment demonstrate that the insensitivity of soybean yield to the previous crop allows for flexibility incorporating soybean into rotations and that regardless of the previous winter crop, yield is typically optimized with a MG V cultivar or later when standard management practices are employed.}, number={1}, journal={AGRONOMY JOURNAL}, publisher={Wiley}, author={Gross, MaKayla R. and Vann, Rachel Atwell and Woodley, Alex L. and Jordan, David}, year={2022}, month={Jan} }
 @article{woodley_drury_yang_phillips_reynolds_calder_oloya_2020, title={Ammonia volatilization, nitrous oxide emissions, and corn yields as influenced by nitrogen placement and enhanced efficiency fertilizers}, url={https://doi.org/10.1002/saj2.20079}, DOI={10.1002/saj2.20079}, abstractNote={AbstractEnsuring sufficient fertilizer nitrogen (N) for crops while minimizing N losses requires best management practices optimized for climate, crop, soil, and root zone hydrology. In Ontario, pre‐plant N fertilization of corn (Zea mays L.) is common; however, this practice extends the time between application and significant root interception of N by the plant, potentially increasing the risk of N loss through soil nitrous oxide emissions, ammonia (NH3) volatilization, and nitrate leaching. These losses contribute to greenhouse gas emissions, affect air quality (NH3), and are a substantial financial loss. This study compared three N placement methods (broadcast urea [BrUrea], broadcast incorporated urea [BrIncUrea], and injected urea ammonium nitrate [InjUAN]) and the presence or absence of N metabolite inhibitors (urease inhibitor [UI], urease plus nitrification inhibitor [UI+NI]). Fertilizer N was applied immediately before planting (150 kg N ha−1) to all treatments except for the control. Averaged over 3 yr (2015–2017), NH3 losses were reduced by 34% from BrIncUrea, by 42–55% from BrUrea+UI+NI and BrIncUrea+UI+NI, and by 99% from InjUAN relative to BrUrea (21 kg N ha−1). On average, N application increased corn grain yields by 83% relative to the control (6 t ha−1). There were no annual yield differences among N placement methods. It was concluded that incorporation or injection of N in soil and use of urease and nitrification inhibitors reduced NH3 emissions when N fertilizer was applied pre‐plant.}, journal={Soil Science Society of America Journal}, author={Woodley, Alex L. and Drury, Craig F. and Yang, Xueming Y. and Phillips, Lori A. and Reynolds, Daniel W. and Calder, Wayne and Oloya, Tom Okello}, year={2020}, month={Jul} }
 @article{carr_cavigelli_darby_delate_eberly_fryer_gramig_heckman_mallory_reeve_et al._2020, title={Green and animal manure use in organic field crop systems}, volume={112}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85080050121&partnerID=MN8TOARS}, DOI={10.1002/agj2.20082}, abstractNote={AbstractDual‐use cover/green manure (CGM) crops and animal manure are used to supply nitrogen (N) and phosphorus (P) to organically grown field crops. A comprehensive review of previous research was conducted to identify how CGM crops and animal manure have been used to meet N and P needs of organic field crops, and to identify knowledge gaps to direct future research efforts. Results indicate that: (a) CGM crops are used to provide N to subsequent cash crops in rotations; (b) CGM‐supplied N generally can meet field crop needs in warm, humid regions but is insufficient for organic grain crops grown in cool and sub‐humid regions; (c) adoption of conservation tillage practices can create or exacerbate N deficiencies; (d) excess N and P can result where animal manures are accessible if application rates are not carefully managed; and (e) integrating animal grazing into organic field crop systems has potential benefits but is generally not practiced. Work is needed to better understand the mechanisms governing the release of N by CGM crops to subsequent cash crops, and the legacy effects of animal manure applications in cool and sub‐humid regions. The benefits and synergies that can occur by combining targeted animal grazing and CGMs on soil N, P, and other nutrients should be investigated. Improved communication and networking among researchers can aid efforts to solve soil fertility challenges faced by organic farmers when growing field crops in North America and elsewhere.}, number={2}, journal={Agronomy Journal}, author={Carr, P.M. and Cavigelli, M.A. and Darby, H. and Delate, K. and Eberly, J.O. and Fryer, H.K. and Gramig, G.G. and Heckman, J.R. and Mallory, E.B. and Reeve, J.R. and et al.}, year={2020}, pages={648–674} }
 @article{drury_woodley_reynolds_yang_phillips_rehmann_calder_2021, title={Impacts of corn stover removal on carbon dioxide and nitrous oxide emissions}, volume={85}, ISSN={["1435-0661"]}, url={https://doi.org/10.1002/saj2.20104}, DOI={10.1002/saj2.20104}, abstractNote={AbstractHarvesting corn (Zea mays L.) stover for production of biofuels, industrial sugars, bioproducts, and livestock bedding is increasing rapidly, but little is known of the impacts of stover removal on soil‐borne greenhouse gas (GHG) emissions. This study evaluated the impacts of removing surface corn stover (0, 25, 50, 75, 100 wt. % removal) on carbon dioxide (CO2) and nitrous oxide (N2O) emissions from a sandy loam soil cropped to monoculture corn using conventional moldboard plow tillage (CT) and no‐tillage (NT). Stover removal systematically decreased CO2 emissions from CT, whereas stover removal had little effect on CO2 emissions from NT. In particular, the CT 0% stover removal treatment produced 47% greater CO2 emissions (5.75 Mg CO2–C ha−1) than the CT 100% removal (3.91 Mg CO2–C ha−1) treatment. Stover removal increased N2O emissions from both tillage treatments, producing up to a 75% increase under CT (2.79 kg N ha−1 at 0% removal; 4.87 kg N ha−1 at 100% removal) and up to a 95% increase under NT (1.75 kg N ha−1 at 0% removal; 3.41 kg N ha−1 at 100% removal). Cumulative nitrate exposure increased in comparable patterns to N2O emissions when stover residues were removed. There was a trade‐off in GHG emissions resulting from stover removal under CT, whereby increasing stover removal reduced CO2 emissions but increased N2O emissions. In contrast, stover removal did not affect CO2 emissions under NT but it increased N2O emissions especially at the 100% removal rates.}, number={5}, journal={SOIL SCIENCE SOCIETY OF AMERICA JOURNAL}, author={Drury, C. F. and Woodley, A. L. and Reynolds, W. D. and Yang, X. M. and Phillips, L. A. and Rehmann, L. and Calder, W.}, year={2021}, month={Sep}, pages={1334–1348} }
 @misc{carr_cavigelli_darby_delate_eberly_gramig_heckman_mallory_reeve_silva_et al._2019, title={Nutrient Cycling in Organic Field Crops in Canada and the United States}, volume={111}, ISSN={["1435-0645"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85078252023&partnerID=MN8TOARS}, DOI={10.2134/agronj2019.04.0275}, abstractNote={Organic farmers have identified soil fertility and weed management as the two highest research priority areas. No review exists of research on soil nutrient management in organic field crop systems. We conducted a comprehensive review to identify the principles and factors governing nutrient management, knowledge gaps, and future research needs in organic grain and other field crop systems in Canada and the United States. We compared results from research conducted in different climates, soils, and crop rotational sequences. Results indicate that (i) dual‐use cover/green manure crops and/or animal manure are the most common sources of plant available N and other nutrients in organic field crop systems; (ii) soil nutrient deficiencies can develop through sole reliance on cover/green manure crops; (iii) dependence on animal manure can lead to N and P excesses; (iv) conventional soil testing procedures may not accurately predict crop nutrient needs; (v) greater knowledge of microbial processes governing nutrient cycling is needed; and (vi) better understanding of the impact of weeds on soil fertility may create weed and nutrient management synergies. Knowledge gaps include a lack in understanding of how the soil and plant biomes influence nutrient‐use efficiency and how crop diversity and rotations impact soil fertility, sustainability, and resilience in organic field crop systems. Likewise, interactions between weeds, crops, soil fertility, and weed management strategies are poorly understood.Core Ideas

Soil, climate, fertility sources, and land use impact organic nutrient management strategies.
Cover/green manure crops and animal manures are used to maintain soil fertility on organic farms.
Conventional soil testing may not be ideally suited to organic systems.
Tracking soil nutrient temporal changes can improve comprehensive nutrient management plans.
More research of how weeds and soil microbial community structure/function impact nutrient cycling and crop production is needed.
}, number={6}, journal={AGRONOMY JOURNAL}, author={Carr, Patrick M. and Cavigelli, Michel A. and Darby, Heather and Delate, Kathleen and Eberly, Jed O. and Gramig, Greta G. and Heckman, Joseph R. and Mallory, Ellen B. and Reeve, Jennifer R. and Silva, Erin M. and et al.}, year={2019}, pages={2769–2785} }
 @article{woodley_drury_reynolds_calder_yang_oloya_2018, title={Improved acid trap methodology for determining ammonia volatilization in wind tunnel experiments}, volume={98}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85042844678&partnerID=MN8TOARS}, DOI={10.1139/cjss-2017-0081}, abstractNote={Abstract: Nitrogen loss through ammonia volatilization is an environmental and economic concern. When acid traps are used with wind tunnels to measure ammonia volatilization, loss of solution volume is observed. As the loss mechanism affects volatilization estimates, a field study was conducted to determine if solution loss from acid traps was due to either selective loss of water through evaporation, loss of bulk solution, or a combination. Two methods for calculating air flow volume through the acid traps were also examined. Solution losses from acid traps averaged 40 mL d-1 (±9.2 mL) from an initial 100 mL, and ammonium concentration increased in close accordance with the dilution–concentration relationship for aqueous solutions. Hence, solution loss was due to evaporation, with virtually no ammonium loss, confirming that the flux calculations using corrected acid trap volumes are required. Failure to correct for the reduced volumes resulted in 9%–224% overestimation of ammonium concentrations. Air flow volumes through acid traps were underestimated by 18.5% when initial and final air flow rates were used compared with continuous cumulative flow measurements. Using cumulative flows and accounting for evaporation loss from acid traps help ensure that treatment differences are not masked by the inherent variability in field-based measurements.}, number={2}, journal={Canadian Journal of Soil Science}, author={Woodley, A.L. and Drury, C.F. and Reynolds, W.D. and Calder, W. and Yang, X.M. and Oloya, T.O.}, year={2018}, pages={193–199} }
 @article{woodley_drury_reynolds_tan_yang_oloya_2018, title={Long-term cropping effects on partitioning of water flow and nitrate loss between surface runoff and tile drainage}, volume={47}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85049473924&partnerID=MN8TOARS}, DOI={10.2134/jeq2017.07.0292}, abstractNote={Surface runoff and tile drainage are the main pathways for water movement and entry of agricultural nitrate into water resources. The objective of this 5‐yr study was to characterize the partitioning of water flow and nitrate loss between these pathways for a humid‐temperate Brookston clay loam soil under 54 to 59 yr of consistent cropping and fertilization. Cropping treatments included monoculture corn (Zea mays L., MC), continuous bluegrass (Poa pratensis L.) sod (CS), and a corn–oat–alfalfa (Medicago sativa L.)–alfalfa rotation (RC–RO–RA1–RA2). Fertilization treatments included annual fertilizer addition (F) and no fertilizer addition (NF). Tile drainage and surface runoff occurred primarily during the nongrowing season (November–April), and they were highly correlated with the mean saturated hydraulic conductivity of the near‐surface soil profile. Tile drainage accounted for 69 to 90% of cumulative water flow and 79 to 96% of cumulative nitrate loss from fertilized rotation and CS, whereas surface runoff accounted for the majority of the nitrate losses in MC (i.e., 75–93% of water flow and 65–96% of nitrate loss). Cumulative nitrate losses were highest in the RC‐F (152 kg N ha−1), RC‐NF (101 kg N ha−1), RA2‐F (121 kg N ha−1), and RA2‐NF (75 kg N ha−1) plots, and these high losses are attributed to N mineralization from the plowed alfalfa and fertilization (if applicable). Fertilization increased cumulative nitrate loss in tile drainage from all treatments, whereas no fertilization increased cumulative nitrate loss in surface runoff from the rotation. Cropping system and fertilization on clay loam soil changed how water flow and nitrate loss were partitioned between tile drainage and surface runoff.Core Ideas
Water partitioning is highly correlated with mean saturated hydraulic conductivity.
Tile drainage was the main pathway of water flow and nitrate loss in rotation plots.
Surface runoff was the main pathway of water flow and nitrate loss in monoculture corn.
Fertilization increased nitrate loss and water flow through tile drainage.
Average nitrate loss was 36% greater in the rotation plots versus monoculture corn.
}, number={4}, journal={Journal of Environmental Quality}, author={Woodley, A.L. and Drury, C.F. and Reynolds, W.D. and Tan, C.S. and Yang, X.M. and Oloya, T.O.}, year={2018}, pages={820–829} }
 @article{woodley_drury_yang_reynolds_calder_oloya_2018, title={Streaming urea ammonium nitrate with or without enhanced efficiency products impacted corn yields, ammonia, and nitrous oxide emissions}, volume={110}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85042845695&partnerID=MN8TOARS}, DOI={10.2134/agronj2017.07.0406}, abstractNote={Core Ideas
Streaming urea ammonium nitrate resulted in 11% lower corn yields compared to injected urea ammonium nitrate.Ammonia volatilization (NH3) begins immediately after application for streaming urea ammonium nitrate.In 2015–2016, NH3 loss was 3.6 fold greater for streaming urea ammonium nitrate compared to injected urea ammonium nitrate.Urease and nitrification inhibitors did not increase corn yields with streaming urea ammonium nitrate.Streaming urea ammonium nitrate with a urease inhibitor increased N2O emissions by 18.7%.
Surface streaming urea ammonium nitrate (UAN) into corn (Zea mays L.) at side‐dress (v4–v6) or later in the season (v12–v14) is an emerging N fertilizer application method as it is rapid, reduces soil disturbance, and allows for flexible application times. In 2013 and 2014, side‐dress N application (130 kg N ha−1) using three streaming UAN sources was evaluated for their ability to maintain grain yield, reduce ammonia (NH3) volatilization, and mitigate nitrous oxide (N2O) emissions. The products included streaming of urea ammonium nitrate (StrUAN), urea ammonium nitrate with a urease inhibitor (StrUAN‐UI), urea ammonium nitrate with urease inhibitor plus nitrification inhibitor (StrUAN‐UI+NI), and a control (no N). The efficacy of streaming relative to traditional shallow‐injected urea ammonium nitrate (InjUAN) was also assessed. Delayed NH3 sampling related to wind‐tunnel installation in 2013 and 2014 led to additional NH3 measurements in 2015 and 2016. Average yields from StrUAN were 11% lower relative to InjUAN. The use of inhibitors did not improve yields relative to StrUAN. Ammonia volatilization was not significantly different between StrUAN and InjUAN losing 14 and 20% of applied N (2‐yr average), respectively. However in 2015 and 2016, NH3 volatilization from StrUAN was 3.6‐fold greater than InjUAN when measurements were started immediately after application. Hence lower yields in 2013 and 2014 from StrUAN likely reflect N loss to rapid volatilization during or shortly after application. The StrUAN‐UI treatment increased 2‐yr average N2O emissions by 17.3 to 18.7% relative to StrUAN or StrUAN‐UI+NI. For humid‐temperate clay loam soil, UAN streaming with/without inhibitors was not effective for maintaining yields or reducing NH3 volatilization.}, number={2}, journal={Agronomy Journal}, author={Woodley, A.L. and Drury, C.F. and Yang, X.M. and Reynolds, W.D. and Calder, W. and Oloya, T.O.}, year={2018}, pages={444–454} }
 @article{drury_yang_reynolds_calder_oloya_woodley_2017, title={Combining urease and nitrification inhibitors with incorporation reduces ammonia and nitrous oxide emissions and increases corn yields}, volume={46}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85029676634&partnerID=MN8TOARS}, DOI={10.2134/jeq2017.03.0106}, abstractNote={Less than 50% of applied nitrogen (N) fertilizer is typically recovered by corn (Zea mays L.) due to climatic constraints, soil degradation, overapplication, and losses to air and water. Two application methods, two N sources, and two inhibitors were evaluated to reduce N losses and enhance crop uptake. The treatments included broadcast urea (BrUrea), BrUrea with a urease inhibitor (BrUrea+UI), BrUrea with a urease and a nitrification inhibitor (BrUrea+UI+NI), injection of urea ammonium nitrate (InjUAN), and injected with one or both inhibitors (InjUAN+UI, InjUAN+UI+NI), and a control. The BrUrea treatment lost 50% (64.4 kg N ha−1) of the applied N due to ammonia volatilization, but losses were reduced by 64% with BrUrea+UI+NI (23.0 kg N ha−1) and by 60% with InjUAN (26.1 kg N ha−1). Ammonia losses were lower and crop yields were greater in 2014 than 2013 as a result of the more favorable weather when N was applied in 2014. When ammonia volatilization was reduced by adding a urease inhibitor, N2O emissions were increased by 30 to 31% with BrUrea+UI and InjUAN+UI compared with BrUrea and InjUAN, respectively. Pollution swapping was avoided when both inhibitors were used (BrUrea+UI+NI, InjUAN+UI+NI) as both ammonia volatilization and N2O emissions were reduced, and corn grain yields increased by 5% with BrUrea+UI+NI and by 7% with InjUAN+UI+NI compared with BrUrea and InjUAN, respectively. The combination of two N management strategies (InjUAN+UI+NI) increased yields by 19% (12.9 t ha−1) compared with BrUrea (10.8 t ha−1).Core Ideas
Ammonia volatilization resulted in 50% loss of applied urea over 2 yr.
When urease inhibitors were added with urea, ammonia volatilization was reduced by 64%.
Injection of UAN reduced ammonia volatilization by 60% compared with broadcast urea.
N2O emissions were increased by 30 to 31% when urease inhibitors were applied.
Pollution swapping was avoided when both urease and nitrification inhibitors were used.
}, number={5}, journal={Journal of Environmental Quality}, author={Drury, C.F. and Yang, X. and Reynolds, W.D. and Calder, W. and Oloya, T.O. and Woodley, A.L.}, year={2017}, pages={939–949} }
 @inbook{woodley_audette_fraser_arcand_voroney_knight_lynch_2014, title={Nitrogen and phosphorus fertility management in organic field crop production}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84937570091&partnerID=MN8TOARS}, DOI={10.1201/b16044}, booktitle={Managing Energy, Nutrients, and Pests in Organic Field Crops}, author={Woodley, A. and Audette, Y. and Fraser, T. and Arcand, M.M. and Voroney, P. and Knight, J.D. and Lynch, D.H.}, year={2014}, pages={59–106} }