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Graham, C
Platero, M
Ruiz Diaz, D.A
Burt, J.P
Sweets, L.E
Bastos, L
Ritchey, E.L
McGrath, J
Lindsey, L.E
Joern, B.C
Burdick, B.A
Nelson, K.A
Grant, C
McVay, K.A
Davis, J.G
Grigera, M.S
Stevens, W.E
Roa , G
Dietrick, K.A
Wortmann, C
Shaver, T
Fairchild, D
West, J
Sharma, L
Lehman, M
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Authors
Schulz, E
Franzen, D.W
Graham, C
Sharma, L.K
Wortmann, C
Shapiro, C
Schmer, M
Bardella, G
Flaten, D
Lawley, Y
Heard, J
Lange, D
Grant, C
Franzen, D.W
Sharma, L
Bu, H
Hankinson, M
Lindsey, L.E
Barker, D
Culman, S
Kaur, G
Motavalli, P.P
Nelson, K.A
Fritschi, F.B
Buchholz, D.D
Stecker, J.A
McVay, K.A
Wollenhaupt, N.C
Schmitt, M
Fairchild, D
Burt, J.P
Rehm, G.W
Lamb, J.A
Malzer, G.L
Davis, J.G
Baxter, C.A
Joern, B.C
Adeola, O
Motavalli, P.P
Nelson, K.A
Stevens, G
Phurahong, S
Grigera, M.S
Drijber, R.A
Wienhold, B.J
Abunyewa, A
Ferguson, R
Wortmann, C
Lyon, D
Mason, S
Tarkalson, D
Shetley, J.M
Nelson, K.A
Burdick, B.A
Motavalli, P.P
Stevens, W.E
Sweets, L.E
Dietrick, K.A
Mullen, R.W
Dygert, C.E
Wortmann, C
Shapiro, C
Ferguson, R
Mainz, M
Franzen, D.W
Sharma, L
Bu, H
Franzen, D
Sharma, L
Franzen, D.W
Sharma, L
Bu, H
Francis, H
Ruark, M
Zegler, C
Smith, D
West, J
Weber, C
Ruiz Diaz, D.A
Bastos, L
Crowther, J
Parrish, J
Ferguson, R
Luck, J
Glewen, K
Shaver, T
Krull, D
Thompson, L
Mueller, N
Krienke, B
Mieno, T
Ingram, T
Parrish, J
Ferguson, R
Luck, J
Glewen, K
Thompson, L
Krienke, B
Mueller, N
Ingram, T
Krull, D
Crowther, J
Shaver, T
Mieno, T
Fitzgerald, L
Ritchey, E
McGrath, J
Shockley, J
Poffenbarger, H
Roa , G
Ruiz Diaz, D
Roa, G
Ruiz Diaz, D
Rutter, B
Winter, C
Clark, J
Lehman, M
Xu, S
Ireland, S
Roa , G
Ruiz Diaz, D
Sadeghpour, A
Adeyemi, O
Guzel, O
Kula, C
McGrath, J
Sener Guzel, G
Sadeghpour, A
Guzel, M
McGrath, J
Adeyemi, O
Arnall, B
Guzel, O
Singh , G
Lory, J.A
Nelson, K.A
Davis, M
Abendroth, L
Kaur, G
Calhoun, J
Chlapecka, J
Bourns, M.A
Nelson, N.O
Ruiz Diaz, D
Roa, G
Ritchey, E.L
Grove, J.H
Teutsch, C
Javid, M
McGrath, J
Babaei, S
Sheikhi Shahrivar, F
Sadeghpour, A
Adeyemi, F
Adeyemi, O
McGrath, J
Armstrong, S
Sadeghpour, A
Guzel, O
Sadeghpour, A
McGrath, J
Platero, M
Morinigo Ferreira, P
Ruiz Diaz, D
Tomlinson, P
Topics
N fixation in cover crop systems
Comparisons of “new” soil test methods
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Filter results39 paper(s) found.

1. No-till Nitrogen Management Research in Missouri

No-till nitrogen management research on corn in Missouri has focused on the field response of N sources and placement. Results suggest consistent significant response to the use of a non-volatile N source when broadcast on the soil surface compared to N sources that contain urea and potentially can lose ammonia through volatilization. Knifed application of N in no-till has . consistently provided higher yields and N uptake compared to either surface band or broadcast application of potentially volatile...

2. Economic Perspective on Variable Rate Fertilization

Soils form a continuum across every farmer's field, constantly changing in both physical and chemical characteristics. Sometimes these changes are visible; sometimes they are completely masked to the eye. Variables such as organic matter, water-holding capacity, pH, and soil nutrient levels differ, and combined, they affect crop yield goals. In either case, these differences should result in different management practices, including fertilizer applications, being recommended for different soils within...

3. What's Ahead- Soil Conservation Service Nutrient Management Plans

Farmers have been going through a major change in their relationship with Government during the past ten years. Many in the agricultural community are anticipating possibly more changes in the future from such Legislation as the Clean Water Act and the Endangered Species Act. Each act has potential of having even more impact on the agricultural community. Immediately following those two acts will be the 1995 Farm Bill. The last two Farm bills have been slanted more to environmental concerns than...

4. Spacial Variability of Soil Test Phosphorus in a Northern Corn Belt Field

For some time, an increasing number of fertilizer dealers, crop consultants, and farmers have reported substantial year-to- year variability in soil test values for phosphorus (P) and potassium (K). Frequently, this variation could be explained by such factors as extremes in soil moisture content at the time of sample collection. In many situations, however, this variation was due to the fact that soil samples were not collected from the same location in the field in two consecutive years. The introduction...

5. Dietary P Management to Reduce Soil P Loading from Pig Manure

The potential use of phosphorus (P) based land application limits for animal manure has increased the importance of optimizing animal feed P management. The specific objectives of this study were to determine the impacts of using high available P (HAP) corn and phytase on 1) P uptake and excretion by young pigs, and 2) total P, PA-P, and water-soluble P (WSP) levels in fiesh manure generated by these pigs during a seven day digestibility trial. Our results show that, compared to the control diet,...

6. Foliar Applications of K on Soybeans

Use of foliar K fertilization has been extensively researched starting in the 1970's with relatively variable and inconsistent soybean yield response. However recent developments which have increased the observed incidence of I glyphosate-resistant soybeans nlay make foliar I fertilization practice may improvc the flexibility of growers to respond to decreased K availability during the growing season because of changes in environmental and rnanagement conditions. This paper details the results of...

7. Arbuscular Mycorrhizal Dynamics Throughout Corn Growing Season

Phosphorous is an essential plant nutrient and is the second most common fertilizer nutrient applied in crop production. The role of mycorrhizal fungi in phosphorous (P) nutrition of corn (Zea mays L.) in high fertility soils in unclear. A study was conducted to determine the effect of extractable P on myco~hizal biomass and to evaluate the temporal dynamics of mycorrhizal fungi during the growing season in two irrigated corn fields in Nebraska. The objectives were addressed by the installation of...

8. Skip-Row Configuration and Plant Density Effects on Sorghum Grain Yield and Yield Component in Southern Nebraska

Equal spacing of sorghum rows typically results in the highest grain yield when soil water is adequate throughout the season, but skip-row plan ting may be a means to reduce water deficits during reproductive growth stages. We evaluated the effect of skip-row planting configuration and plant population density on grain yield, yield components and water use efficiency at five locations in a transect across southern Nebras ka where annual mean precipitation ranges from 300 to 900 mm yr -1. Three row...

9. Use Of Corn Height To Improve The Relationship Between Active Optical Sensor Readings And Yield Estimates

Pre-season and early in-season loss of N continues to be a problem in corn (Zea mays, L.). One method to improve nitrogen use efficiency is to fertilize based on in-season crop foliage sensors. The objective of this study was to evaluate two different ground-based, active-optical sensors and explore the use of corn height with sensor readings for improved relationship with corn yield. Two different ground-based active-optical sensors (Greenseeker�, Trimble, Sunnydale, CA; and Holland Crop Circle...

10. Crop Yield Relationship to Remote Sensing Data Using Intensified Weighted Nonlinear Regression Models

Yield prediction is important for making in-season agronomic input decisions as well as for greater logistical decisions. In predicting the crop yield based on ground-based active optical sensing data, the ordinary statistical unweighted linear or nonlinear regression models are the most popular choices. However, these unweighted models may not be accurate enough for practical use because they are based on the assumption that each data point for regression is obtained with equal precision and that...

11. Nitrogen Rate Revisions for Corn in North Dakota

Nitrogen rates in North Dakota have been based on a yield-goal or yield-potential formula for over forty years. The currently published formula (Franzen, 2010) is: Recommended N rate = (Yield Potential, bushels per acre) X 1.2 less N credits from previous crops and soil test nitrate to 2 feet in depth. A yield-based strategy was practical when N costs were relatively low and yields in North Dakota were at most 100 bushels per acre. However, due to improved germplasm developed at North Dakota State...

12. Nitrogen and Phosphorus Recalibration for Sunflower in the Northern Great Plains

Sunflower producers in the northern Great Plains states of North Dakota, South Dakota, and Minnesota are presently directed to N and P recommendations that originate from research performed in the late 1960s and early 1970s. These three states alone produce more than 80% of the sunflowers in the United States on a yearly basis (USDA-NASS, 2015). The current general formulas determining N and P fertilizer rate in these top-producing states are equivalent. The N recommendation is represented here by...

13. Residue Harvest Effect on Irrigated, No-till Corn Yield and Nitrogen Response

Immobilization of applied N is expected when much high C:N crop residue remains in the field as is typical following corn grain harvest. Immobilization of N is expected to be less if crop residue is less. The effect of reduced immobilization on N availability may more than compensate for N removed in residue harvest. Therefore, applied N requirement for a following corn crop may be less if crop residue is reduced through harvest. Residue removal decreased the economically optimal N rate (EONR) by...

14. 4R Phosphorus Management for Soybeans in the Northern Frontier: Rate and Placement Effects on Plant Stand, Biomass and Seed Yield

Very little research has been conducted to determine the best rate, source, placement, and timing of P fertilizer for modern soybean cultivars grown in the Canadian Prairies. Preliminary results of the two years of field studies at 10 locations in Manitoba showed that typical agronomic rates of seed row P did not decrease plant stand and seed yield at any sites; nor was seed yield increased at any site, even with Olsen P concentrations as low as 3 ppm....

15. North Dakota Corn Recommendations for Preplant and Sensor Directed Sidedress N

Nitrogen rates for preplant N application in North Dakota have been drastically revised. The former yield-based strategy may have served when N costs were stable and relatively low and high yields in North Dakota were rarely higher than 100 bushels per acre. Due to improved germplasm developed at North Dakota State University and other northern Land-Grant Universities with favorable adaptation to North Dakota climate and soil conditions corn has become one of the most planted crops in the state....

16. Effect of Starter Fertilizer and Plant Date on Soybean Growth, Nodulation, and Yield

Environmental conditions at the time of planting are a crucial determinant to soybean (Glycine max) yield potential. In recent years, it has become common in Ohio to begin planting earlier in the growing season, as soon as mid- or late-April in some cases. However, soil conditions are typically cooler and wetter at this time as opposed to later planting dates, and nutrient availability may be limited. When planting soybeans into cool and wet soil, the application of a starter fertilizer may be beneficial...

17. Use of Nitrogen Fertilizer Sources to Enhance Tolerance and Recovery of New Corn Hybrids from Early Season Soil Waterlogging

Corn (Zea mays L.) production losses due to temporarily flooded or saturated soils resulting from excessive precipitation are a persistent problem in Missouri and the Midwest Region of the United States. In 2011 alone, monetary losses for corn and soybean (Glycine max) production due to excessive flooding in the Midwest were calculated to be more than $1.6 billion. Application of different sources of nitrogen (N) fertilizer may promote increased flood tolerance and recovery in interaction with different...

18. Irigated Soybean Response to Nitroen Applied During Early Pod Formation

High yield soybean ( Glycine max L.) has a high rate of N uptake during grain fill with maybe 2/3 of the N derived from the atmosphere. The rema ining needs to come from the soil. Previous research has found that the probability of response to N applied at early pod development (R3) for yield trials, including 44 with mean yield >60 bu/A, we re conducted in Nebraska to determine effect on soybean yield of applying N and S to the soil at R3. With 27 lb/A N applied and >60 bu/A yield, mean yield increases...

19. Foliar Fertilizer and Pyracolstrobin Fungicide Combinations for Corn

Incorporating a foliar applied fert ilizer with fungicide application could reduce application costs, improve disease suppression, increase nutrient re sponse, and enhance the management of crop response to environmental conditions within th e growing season. A two-year field trial was initiated in 2008 at three sites in northeast, southeast and northwest Mi ssouri. Treatments consisted of a factorial arrangement of 13 diffe rent commercially-available foliar fertilizers containing both macro- and...

20. Impact of Phosphorus and Potassium Fertilization on Corn and Soybean Productivity and Soil Nutrient Levels

A common production practice in the Eastern Corn Belt is to supply enough phosphorus (P) and potassium (K) in the fall prior to corn planting to satisfy the nutrient needs of both corn and soybeans in a rotation. This practice is most likely a viavle option for fields with more than adequate soil nutrient levels, but on marginal fields this practice may be limiting production (specifically with regard to K). Two field experiements were estabished to evauate the impact of P and K fertilization... K.A. Dietrick, R.W. Mullen, C.E. Dygert

21. Nitrogen benefits when interseeding red clover into continuous corn

Information pertaining to the benefits of intereseeding cover crops is lacking. Red clover is a leguminous cover crop that can grow in low radiation environments, is winter hardy for much of the northern USA, and is a low cost weed suppressant that has been shown to provide a nitrogen credit and improve corn yield. While it is clear that red clover is a cover crop that can provide immediate economic benefits in grain-based cropping systems, the potential N credit and the effect of interseeding... H. Francis, M. Ruark, C. Zegler, D. Smith, J. West

22. Evaluation of Soil Test Methods and Crop Response to Phosphorus Fertilization in Kansas

Wheat (Triticum aestivum) is typically considered the most responsive crop to phosphorus (P) fertilization in Kansas. This study was conducted to evaluate wheat response to P fertilization using modern genotypes and soil test calibration/interpretation for Kansas soils. The study was conducted during the 2018-2019 growing season with eleven locations in Kansas. Randomized complete block design was used for four different... C. Weber, D.A. Ruiz diaz

23. Not All Litter is Created Equal: Differences in Nitrogen Mineralization Among Broiler Litter Types

Over three fourths of U.S. broiler chicken production is located in the Southeast and generates a substantial amount of broiler litter (BL). Broiler litter is a mixture of bedding material and manure that can be a valuable nutrient source for row crop production when properly used. New technologies provide farmers with the opportunity to use a combination of BL and inorganic fertilizers with minimal environmental impact. The first part of the project evaluated integrated N management systems that... L. Fitzgerald, E. Ritchey, J. Mcgrath, J. Shockley, H. Poffenbarger

24. Nitrification Inhibitor Value in Irrigated Corn: Insights From a Long-term Study

Proper nitrogen (N) nutrition is key to optimizing corn yields. Due to its dynamic behavior in soils, N can be lost through different pathways and negatively impact corn production. Nitrification inhibitors (NI) decrease the rate of ammonium transformation to nitrate in the soil, potentially decreasing denitrification and leaching potential. However, NI only has a positive effect on yield if environmental conditions are conducive to loss to the point of N becoming limiting to crop performance.... L. Bastos

25. Integrating Management Zones and Canopy Sensing for Improved Nitrogen Recommendation Algorithms

Active crop canopy sensors have been studied as a tool to direct spatially variable nitrogen (N) fertilizer applications in maize, with the goal of increasing the synchrony between N supply and crop demand and thus improving N use efficiency (NUE). However, N recommendation algorithms have often proven inaccurate in certain subfield regions due to local spatial variability. Modifying these algorithms by integrating soil-based management zones (MZ) may improve their accuracy... J. Crowther, J. Parrish, R. Ferguson, J. Luck, K. Glewen, T. Shaver, D. Krull, L. Thompson, N. Mueller, B. Krienke, T. Mieno, T. Ingram

26. Comparison of Ground-Based Active Crop Canopy Sensor and Aerial Passive Crop Canopy Sensor for In-Season Nitrogen Management

Crop canopy sensors represent one tool available to help calculate a reactive in-season nitrogen (N) application rate in corn. When utilizing such systems, corn growers must decide between using active versus passive crop canopy sensors. The objectives of this study was to 1) determine the correlation between N management by remote sensing using a passive sensor and N management using proximal sensing with an active sensors. Treatments were arranged as field length strips in a randomized complete... J. Parrish, R. Ferguson, J. Luck, K. Glewen, L. Thompson, B. Krienke, N. Mueller, T. Ingram, D. Krull, J. Crowther, T. Shaver, T. Mieno

27. Corn Response to Phosphorus Fertilization and Evaluation of Soil Test Methods in Kansas Soils

Phosphorus is a critical nutrient in corn (Zea mays L.) production, and limitation in P availability can result in significant yield reduction. The objective of this study was to evaluate corn response to phosphorus fertilization and evaluate multiple soil test methods in Kansas soils. The study was conducted in 13 locations across Kansas during 2021. Fertilizer treatment consisted of five rates of phosphorus (P) fertilizer (0, 30, 60, 90, and 120 lbs. P2O5 acre–1), using mono-ammonium... G. Roa , D. Ruiz diaz

28. Evaluation of Plant Tissue Analysis to Assess Phosphorus Nutritional Status in Corn and Soybean

Plant phosphorus (P) tissue analysis can be used to identify the nutritional status and potential response to P fertilization. This study aimed to determine critical P tissue concentration at different growing stages for corn and soybean. The experiment was conducted across multiple corn and soybean locations in Kansas. Tissue samples were collected as whole plant V6 stage and ear leaf R1 stage in corn, whole plant V4 stage, and trifoliate R3 for soybean. Plant tissue samples were dried, ground,... G. Roa, D. Ruiz diaz, B. Rutter

29. Conservation Practices Lower Soil Test Phosphorus Requirements and Optimize Crop Yield

Sustainable P management in cropping systems is a challenge in modern agriculture. The implementation of conservation practices of no-till, retaining high levels of residue in the field, and diverse crop rotations may create a more suitable environment for arbuscular mycorrhizal fungi (AMF) to accumulate. A greater AMF population may subsequently increase the P available to crops, lowering the soil test P amount needed to optimize crop yield. At the Dakota Lakes Research Farm in Pierre, South... C. Winter, J. Clark, M. Lehman, S. Xu, S. Ireland

30. Assessing Sulfur Response, Utilization Efficiency, and Diagnostic Tools for Corn in Kansas

Efficient sulfur (S) utilization is crucial for crops' productivity and the sustainability of agricultural systems. This study aims to evaluate the effect of sulfur application on corn production across various Kansas sites and determine how sulfur fertilization affects different growth parameters and diagnostic tools for corn. The study was conducted over the 2021-2022 growing seasons, with a comprehensive field experiment carried out across 26 sites in Kansas. A randomized complete block... G. Roa , D. Ruiz diaz

31. Corn Nitrogen Requirement in Winter Cereal Cover Crop Trials in Southern Illinois

Winter cereal cover crops, including wheat (Triticum aestivum L.) and winter rye (Secale cereale L.) are recommended as the best in-field management strategy by the Illinois Nutrient Loss Reduction Strategy (INLRS) to minimize nitrate-N leaching to the Mississippi River Basin and the Gulf of Mexico. We evaluated the effect of wheat and winter rye on corn grain yield, and nitrogen (N) requirement. Treatments were laid out in a randomized complete block design with four replicates... A. Sadeghpour, O. Adeyemi, O. Guzel, C. Kula, J. Mcgrath, G. Sener guzel

32. Does Sensor-based Nitrogen Management Maintain Crop Production and Decrease Nitrate-N Leaching?

To improve water quality, nitrogen (N) management in corn production systems should shift from current N decision support system [maximum return to N (MRTN)] which suggests a single rate N addition to sensor-based (GreenSeeker) active N management (variable N rate approach). Single rate N recommendations often result in under- and over-N addition and either increase environmental N losses or cause corn yield penalty. Our objectives were to evaluate corn optimum nitrogen N requirement (EORN) in... A. Sadeghpour, M. Guzel, J. Mcgrath, O. Adeyemi, B. Arnall, O. Guzel

33. Revamping Nitrogen Fertilizer Recommendations for Missouri

Multiple nitrogen fertilizer rate decision tools have been developed over the years for recommending nitrogen to growers. These tools are based on mass balance equations with expected yield and yield goal, economically optimum nitrogen rate, preplant soil nitrate test, pre-sidedress and late spring soil nitrate test, plant tissue nitrogen, crop growth models, and canopy reflectance sensing. These tools rarely include biological nitrogen in the rate recommendations. Advances in soil health assessment... G. Singh , J.A. Lory, K.A. Nelson, M. Davis, L. Abendroth, G. Kaur, J. Calhoun, J. Chlapecka

34. Developing a Sustainable Sufficiency Paradigm

Sustainable conservation practices must align agronomic productivity and environmental protection goals to facilitate widespread and consistent adoption on-farm. Agricultural phosphorus (P) management is a critical control point for detrimental environmental consequences of P loss in surface runoff from agricultural fields. Reduced P fertilizer inputs are recognized as an effective and necessary control measure to limit P loss; however, current P fertilizer recommendation systems do not support... M.A. Bourns, N.O. Nelson, D. Ruiz diaz, G. Roa

35. Comparing the Effectiveness of Calcium Products in Neutralizing Soil Acidity

Proper pH management is the foundation of a good soil fertility program. Soil pH influences nutrient availability, root growth and function. Acid soils are neutralized by the addition of carbonates, oxides, and hydroxides present in limestone products. However, there is a common perception that calcium is responsible for the neutralization of acid soils rather than the carbonates associated with calcium in the limestone. The effectiveness of three calcium products in raising soil pH were compared... E.L. Ritchey, J.H. Grove, C. Teutsch

36. Assessing Fall Applied Phosphorus Sources and Wheat Cover Crop on the Following Soybean Performance

Growers often maintain soil test phosphorus (STP) using ammonium phosphate fertilizers, such as diammonium phosphate (DAP, 18-46-0) or monoammonium phosphate (MAP, 11-52-0) and employ fall application to avoid competition for time and wet field conditions, both prevalent in the spring. However, fall application of nitrogen (N) with these P fertilizers presents a risk of N loss over the fallow period. One source that could minimize N loss during the fallow period is triple superphosphate (TSP;... M. Javid, J. Mcgrath, S. Babaei, F. Sheikhi shahrivar, A. Sadeghpour

37. Impact of Nitrogen Application Timing on Corn Yield and Farm Profitability in Different Wheat Cover Cropping Systems

The continuous increase in the concentrations of nitrogen (N) and phosphorus (P) in the Upper Mississippi River Basin (UMRB), has led to the introduction of mitigation strategies with the use of winter cereal cover crop such as winter wheat (Triticum aestivum). The understanding of the use of these winter cereal cover crops in relation to soil N and its impact on corn yield is imperative. The study investigates the impact of cover crop termination and N application timing on corn production... F. Adeyemi, O. Adeyemi, J. Mcgrath, S. Armstrong, A. Sadeghpour

38. Assessing the Effectiveness of Green-Seeker Algorithm in Minimizing Nitrogen Loss in Corn Production Systems

To improve water quality, nitrogen (N) management in corn production systems should shift from current N decision support system [maximum return to N (MRTN)] which suggests a single rate N addition to sensor-based (GreenSeeker) active N management (variable N rate approach). Single rate N recommendations often result in under- and over-N addition and either increase environmental N losses or cause corn yield penalty. Our objectives were to evaluate corn optimum nitrogen N requirement (EORN) in... O. Guzel, A. Sadeghpour, J. Mcgrath

39. Enhancing Nitrogen Fertilizer Efficiency in Sorghum to Boost Yields and Reduced Nitrogen Loss

Nitrogen management is crucial in modern farming as it plays a major role in achieving higher yields. This study aimed to identify the optimal nitrogen application rate and best management practices to prevent over-application, nitrogen losses, and nitrogen deficiency in crops. Kansas, a leading state in sorghum production, served as the study's setting. Research was conducted at four sites during 2021 and 2022 on rain-fed fields in North-East and North-West Kansas. The objectives... M. Platero, P. Morinigo ferreira, D. Ruiz diaz, P. Tomlinson