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1. Bandded Phosphorus Applications to Winter Wheat - 1985-86While many producers recognize the importance of a sound P fertilization program for profitable wheat production? there are many potentially responsive wheat acres not receiving any fertilizer P - resulting in reduced grain yields and farmer profitability. over the years there have been many research studies conducted by land grant Universities throughout the Great Plains indicating the importance of fertilizer P applications for wheat production on low P testing soils. In the mid to late 1970's... |
2. Using Sufficiency and Recommendation Information to Calculate Fertilizer Response Curve and Profitability Estimates.The importance of sound fertility programs in efficient, profitable farming operations is well known - especially in times of low crop prices. Likewise, the importance of a sound soil testing program - and recommendation guidelines that relate these soil test values to credible, long-term research results - is recognized as the best way of obtaining maximum economic returns from fertilizer dollars. Unfortunatly, there are few tools available for evaluating the profitabi1it.y of a specific fertility... |
3. Small Grain Response to Potassium and Chloride AdditionsStudies have been conducted over a three-year period to determine the frequency and the cause of small grain response to KC1 additions on high K soils. During the first two years responsiveness of hard red spring wheat, spring barley, and oats were compared at six locations in eastern South Dakota. Broadcast applications of 167 lbs/A of KC1 caused grain yield increases significant at the 0.05 probability level at four sites for wheat and two sites for barley while no oat yield increases were measured.... |
4. Nitrogen Management for no-till Grain SorghumField experiments evaluating the effects of nitrogen management for no-till dryland grain sorghum were coacted in 1985 and 1986. Nitrogen rates (0, 50, 100 lbs N/A and placement methods for urea ammonium nitrate solution (UAN) have been evaluated in eastern Kansas. Placement methods have included surface broadcast, surface banded, pressure injected, and knifed. Results to date shm that nitrogen consistently increases yields and tissue and grain N contents, and that method of UAN placement produces... |
5. The Components of Sustainable AgricultureSustainable agriculture has become a rallying phrase for many concerned about agricultural profitability and environmental quality in the rural sector. Advocates of sustainable agriculture seem to be convinced that the policies and structure of the agricultural industry are responsible for increasing environmental problems, low farm profitability, declining farm numbers, and reduced quality of life in rural America. The agricultural popular press has published numerous stories about those concerned... |
6. Nitrogen Management for Cool Season Grass ProductionStudies were initiated in 1985 on established smooth bromegrass and tall fescue to evaluate urea granule size effects on forage production and quality. Other work, evaluating N source by previous source effects and UAN placement methods and the addition of ATS, was conducted on established smooth bromegrass. Nitroger1 rates were also evaluated in all these studies, and the addition of N significantly increased forage yields and N concentrations in each study. Use of large (1.0g) urea granules produced... |
7. Summary of P Fertilizer use Effects on Soil Test PhosphorusOver the years, much research has centered on the use of various soil P extractants for developing soil fertility programs. While P soil test values are most reliable for estimating the historical probability of obtaining a crop response from fertilizer P application and tracking the effects of past P fertility programs - P soil tests are more commonly used as to estimate future fertilizer P rate requirements. Depending on the objectives of a grower, P soil testing is used to predict future P rate... |
8. Calcium Chloride Effects on Nitrogen Uptake by Small GrainsApplying calcium chloride (CaC12) with urea stimulated nitrogen uptake by small grains in six greenhouse studies. The effect was most dramatic for a sandy soil, moderate for a loam soil, and not observed for a clay soil. Allowing the urea to nitrify before plant uptake negated the CaC12 effect. In field studies, these effects were generally not observed, probably because the nitrification of the applied N was too rapid. However, this concept deserves further investigation, for example, when established... |
9. Forage Quality Management- A Key to Successful Cattle Nutrition ProgramsIn 1992, the USDA reported 59.6 million acres were harvested for hay with an average yield per acre of 2.5 ton per acre. These values gave a projected total yield of 149.1 million tons of harvested hay. Using an average market price of $72.10 per ton, total value of hay produced exceeded 10.5 billion dollars. Also in 1992, alfalfa production represented over 50 percent of the forage harvested with 79.6 million tons produced. In addition to stored forage. pasture is also a significant source of forage... |
10. Strategies for Establishing Management Zones for Site Specific Nutrient ManagementRecent precision agriculture research has focused on the use of management zones as a method to define areas for variable application of crop inputs. The goal of our work was to determine the relative importance of terrain information, aerial photographs, magnetic induction maps, and yield maps to define management zones. This work was conducted on a center-pivot irrigated field located near Gibbon. NE that has been planted to continuous corn for at least five years. Remotely sensed bare-soil images,... |
11. Adjusting N Recommendations Based on a Previously Grown CropNitrogen recommendations in North Dakota are based on a yield goal multiplied from some empirically derived factor in a linear formula. There are a three adjustments to the N recommendations that result form these formulas (Franzen and Cihacek, 1996). They are the soil test nitrate-N to some depth, a sampling date adjustment ifthe sampling was conducted in the fall prior to September 15, and a previous crop credit. Two of these three adjustments are based on some knowledge regarding mineralization... |
12. Site-Specific Management of Iron Deficiency in CornThe addition of FeS04mH20 in the seed row increases corn (Zea mays L.) yield in areas with Fe deficiency-induced chlorosis. Our objectives were to determine the correct application rate of FeS04.H20 for irrigated corn, identi9 the spatial distribution of Fe deficiency, and alleviate deficiency symptoms with targeted FeS04.H20 applications. Eleven site-years were selected for small-plot studies in western Kansas. At these fields, soil CaC03 content in chlorotic or problematic deficient areas of the... |
13. Yield Goal Versus Delta Yield to Predict Nitrogen Need in CornFertilizer nitrogen (N) needs of corn can vary widely both among and within fields. Many states use a yield goal to identi@ differences in fertilizer N need combined with an N credit system to adjust for N provided by the soil from sources such as soil organic matter, residual inorganic N and crop residues. Some have questioned yield-goal derived fertilizer N recommendations because of its poor correlation with fertilizer N need, leading some states to eliminate yield goal from their N recommendation... |
14. Nitrate Leaching Characteristics for Various Nitrogen Management Strategies on Irrigated CornEfficient use of nitrogen (N) fertilizer for corn production is important for maximizing economic return to the producer and minimizing NO3 leaching to groundwater. This is especially important on irrigated, sandy soils due to the high infiltration and saturated conductivity and potential risk to the local water supplies. This study is being conducted to quantifL the NO3 leaching potential in the irrigated sands along Kansas' waterways under current and alternative N and water management strategies... |
15. Evaluation of the Amino Sugar-N Based Soil test in Iowa Corn ProductionAn important improvement in estimating economic N applications for corn production would be to predict the soil N supply capacity each year. The objective of this research is to evaluate the adaptability and potential calibration of the amino sugar-N based Illinois N Soil Test in corn production fields across diverse Iowa soils. Nitrogen rate trials were conducted at multiple sites over several years, many on producer fields. Soil samples were collected at 0-6 and 0-12 inch depths in the fall and... |
16. Fertilizer Management for Strip-till and No-till Corn ProductionStrip-tillage for corn production can be advantageous over no-till. particularly in areas with heavy soils and high rainfall during spring months. Under these conditions in no-till systems. planting delays andlor slow. uneven emergence are common. Strip-tillage creates a narrow tilled area for the seedbed while maintaining the inter-row residue cover, allowing for erosion protection associated with no-till. yet providing an area in the rowr where the soil will dry out and warm up earlier in the season.... |
17. Providing Flexibility in P and K RecommendationsHistorically, land grant Universities have generally provided a single rate recommendation for nutrients such as phosphorus (P) and potassium (K). Depending on the particular University in question, these nutrient rate recommendations are generally based on two widely recognized approaches to managing soil and fertilizer P and K - the nutrient sufficiency approach and the build-maintenance approach. The goal of a nutrient sufficiency based soil fertility program is to apply just enough P andior K... |
18. Comparison of Nitrogen Recommendation Models for Corn in Two Cropping SystemsSeveral lnodels exist to generate N recommendations, and the model selected can have both economical and environmental implications. A study was initiated in 1998 to compare the response of corn to N in two ci-opping systenls (corn following corn and corn following soybeans). All plots received a starter N rate of 45 kg N ha-' (2 x 2 placement). and five rates of sidedress N (0, 22, 90, 157, and 224 kg N hi') were applied at gro~vth stage V6 either as anhydrous arnmonia or urea-ammonium rli trate... |
19. Development of Insite VRN as an Effective Nutrient Management ToolGrowers have significantly increased their yield levels in corn and wheat in the last 10 years. As yields increase. the amount of nutrients required has also increased to supply the crop with needed plant nutrition. Fertilizer application rates in excess of plant needs can increase the likelihood that the fertilizer may end up in ground water and streams. Mosaic developed a nutrient application tool, called Ins i te VRN, which illore accurately positions the fertilizer where it is needed for maximum... |
20. Relationship of Mehlich-3 ICP and Mehlich-3 Colorimetric Phosphorus Determinations with the Bray-P1 ExtractantThe Bray P1 extractant has traditionally been the common extractant used for soil testing in the Midwest and Great Plains. while the Olsen P tests has been the dominant phosphorus (P) extractant used in many westem states. The use of the Meldich-3 extractant for determining soil test P in private and state operated soil test laborato~ies becotne more commonplace in recent years. The ability to extract multiple elements is a 11lajor advantage of the Mehlich-3 test. While the Mehlich-3 test is often... |
21. Impact of Nitrogen and Sulfur Fertilization on Wheat Yield and QualitySulfur (S) contributed by rainfall has decreased by 50% over the last twenty-seven years and may increase the need for S supplementation by fertilization. Nitrogen (N) application is typically split applied in Ohio with some applied in the fall and remainder applied in the spring near first green-up. The objective of this study was to compare N application source and timing with and without S fertilization. Two experimental locations were established in the fall of 2004. Urea and urea-ammonium nitrate... |
22. Introgressing Unique Sources of Germplasm to Improve N Use in Temperate MaizeThe vast majority of maize breeding efforts have been conducted under high N environments that primarily select for only one component of NUE, N uptake. Furthermore, these studies have employed US. and European genotypes, which have been selected for performance at high N. Historically, maize was grown in numerous low N tropical environments, suggesting that evaluation of adapted maize lines containing tropical germplasm may harbor useful genetic variation and novel alleles for improving NUE. The... |
23. An Environmental Assessment of Sensor-Based Variable-Rate Nitrogen Management in CornIn order to address the problem of nitrate contamination of surface and ground waters, various methods have been used to try to account for spatial variability of N within agricultural fields. One approach to account for this variability and thereby reduce nitrate pollution is in-season site- specific N application according to economic optimal N rate (EONR). Recently, active crop canopy sensors have been tested for mid-season, on-the-go N fertilizer application in corn. This 2004 and 2005 study... |
24. Assessment of the Combined Effects of Soil pH and Carbonates on Soybean Yield and Development of Iron Deficiency ChlorosisSoybean is extensively grown in areas of the Midwest where fields often have areas of acid to calcareous soils intermingled in complex spatial patterns. Soil pH is highly buffered by carbonates, and measured pH usually ranges from 7.5 to 8.3 depending on the concentration of C02 and other factors. Soybean grown on high-pH calcareous soils often shows iron (Fe) deficiency chlorosis (IDC). Symptoms of IDC include yellowing of interveinal areas of young leaves and, as the deficiency becomes severe,... |
25. Corn Yield Response to Residual Forage Crop Rotation and Manure Amendment Effect in Potato RotationsAccurate prediction of multiple-year N availability froin organic sources is difficult and can complicate nitrogen management for producers using these sources. The objective of this study was to use corn yield and soil N monitoring to evaluate long-term nutrient availability from rotational systems on an irrigated Alfisol in central Michigan. Over a 5-year period, multiple crop sequences were grown with either annual liquid dairy manure at 12,260 L ha-' or conventional mineral fertilizer application... |
26. Development of Field InSite as an Effective Nutrient Management ToolNitrogen. phosphorus, and potassium are essential nutrients for crop production. Crop nutrient management is critical to the success of any farming operation. Land stewardship is a concern for most producers as long as yields and profitability are not affected significantly. While farmers are eager to improve the efficiency with which they apply nutrients, maintaining expected crop revenue per acre is equally important. Higher fertilizer costs have increased the desire to find better ways to apply... |
27. Impact of Nitrogen and Sulfur Fertilization on Wheat Yield and Quality in 2006Historically, wheat has not responded to supplemental sulfur (S) on fine to medium textured soils with adequate organic matter. However, improved sulfur scrubbers in the industrial sector have decreased the amount of S contributed annually by rainfall. Annual S deposition in Ohio has decreased by 50% over the last twenty-seven years (NADP, 2005). This may lead to greater demand for S in Ohio crops. Recent Oho research showed a positive response to ammonium sulfate but did not have the parameters... |
28. Sulfur and Nitrogen Starter Fertilizer for Corn in Northern ClimatesThe combination of cool and wet weather in early spring can reduce the amount of S and N released in soil by decomposition and mineralization of organic matter, particularly in reduced- tillage or no-till cropping systems. Recent changes to S emission regulations have decreased the amounts of S that is deposited to the soil through attnospheric channels. Field studies were initiated in 2005 at five corn (Zea mays L.) sites in Michigan to evaluate the effects of S and N starter fertilizer on nutrient... |
29. Field Measurements of Nitrous Oxide Emissions across a Nitrogen Fertilizer Gradient for Corn Cropping SystemsSignificant reductions in nitrous oxide (N 2O) emissions from corn (Zea maize L.) cropping systems may be possible by reducing N fertilizer i nputs with relatively little impact on crop grain yield or economic return. To te st this hypothesis, experiments we re conducted at 4 locations in corn production in Michigan in 2007. All sites were under a corn-soybean rotation. Prior to planting, six rates of urea fertilizer (0-200 lb ac -1) were broadcast and incorporated into four replicate plots (RCBD)... |
30. Value of Tillage Practices and Nitrogen Rates for Corn ProductionMost N recommendations for corn (Zea mays L.) production in the U.S. Midwest do not consider tillage as a factor when an appropriate N rate is determined. Our objectives were to determine the response of grain yield and RTN to increasing rates of fertilizer N for corn grown in three tillage systems. Tillage by N rate experiments we re conducted at eight Central Illinois site-years at three locations and years (1998-2000). Tillag e systems employed were: zero-till, where no tillage was performed at... |
31. Evaluation of the Greenseeker Active Sensor for Sugarbeet Cropping System Nitrogen ManagementThe application of adequate, non-excessive rates of N fertilizer to sugarbeets ( Beta vulgaris L.) continues to increase in importance with rising fertilizer costs and industry transitions from yield-based payments to payments weighted towa rd crop quality. The objective of this study is to evaluate the use of an optical sensor for its potential in assessing in-season sugarbeet N status, in-season yield prediction, and total N in foliage on day of harvest. Six N fertilizer treatments, from 0 to 224... |
32. In-Season Nitrogen Management for Corn ProductionWater quality impairment related to nitrogen (N) continues to be a concern in Iowa, including the nitrate drinking water standard, USEPA proposed surface water quality nutrient criteria, and the Gulf of Mexico hypoxia. Addressing these issues could include strict guidance for N input to corn and resultant N use practices that require very high level of management and risk, with unknown economic consequences. Rate of N application is an important ma nagement factor in corn production related to nitrat... |
33. Triple-Stacks, Genetics, and Biotechnology in Improving Nitrogen Use of CornGenetic improvement in N use efficiency (NUE) is a clear strategy fo r enhancing yield and fertilizer N management of corn ( Zea mays L.), and has been the subj ect of our ongoing research. Calculation of the N requirement (N fertilizer usage/grain yield) based on statewide average grain yields and fertilizer sales shows a stead y decrease since the mid 1980's, suggestive of a genetic improvement in N use. Direct comparis on of the response to N for a 1980�۪s hybrid with its modern counterpart... |
34. NUE in Practice: Will N-efficient Corn Hybrids Sell?Efficient use of nitrogen (N) fertilizer is becomi ng increasingly important in corn production due to rising N fertilizer prices and growing concer ns about N contamination of ground and surface waters. Seed companies are also beginning to develop hybrids with N use efficiency (NUE) improved through trait introduction. The introduc tion of such hybrids will bring new questions about the value of higher NUE, and about risk ma nagement associated with decreasing, or not increasing, N use rates as... |
35. Nitrogen Recalibration for Wheat in North DakotaThe general formula for determining N fertilizer ra te in North Dakota for about thirty-five years has been N-rate = (2.5 X Yield Potential (or Yield G oal) less credits from previous crops and soil test nitrate-N from a 2-foot soil core composite. Historically high fertilizer N costs and the ability to fertilize within fiel ds rather than whole field N management has resulted in a reexamination of N calibration data, and an effort to expand the modern N calibration database with new field experiments.... |
36. Delayed-Release Nitrogen Fertilizer Effects on In-Season Soil Nitrogen for Michigan Sugarbeet ProductionDelayed-release N fertilizers have received attention for Michigan sugarbeet production as producers seek to improve the timing of N ava ilability to better match plant demand and to maximize plant N use efficiency. The N release ch aracteristics of these products are particularly important in sugarbeet production, where excessive N availability late in the season can have adverse impacts on crop quality. The objective of this research was to evaluate delayed-release N fertilizer sources, alone... |
37. Incorporating Cover Crops into No-till Production SystemsAlthough no-till soil management has many benef its, including protecting the soil from erosion, improving soil organic matter, and improving soil moisture storage, depending on environmental conditions there could be a number of potentia l problems. Implementation of no-till soil management in eastern South Da kota can lead to wet and cold soils at the time of planting. Cover crops have the potential to utilize exce ss soil moisture and improve soil conditions at planting. A field experiment was... |
38. Evaluation of Wavelength from Ground-Based Active Optical Sensors for Corn Yield Prediction in North DakotaGround-based active-optical (GBAO) crop sensors have been used successfully to predict crop yield when used during early growth stages. The objective of this study was to evaluate two GBAO sensors wavelengths regarding their usefulness under North Dakota corn (Zea mays, L.) growing conditions. Thirty experimental sites were used in North Dakota to conduct N rate trials on corn during 2011 and 2012. All sites were designed as randomized complete blocks with four replications and six nitrogen (N) treatments;... |
39. Can Soil Information Better Inform Canopy Sensor Algorithms for Corn?Corn production is often limited by the loss of nitrogen (N) due to leaching, volatilization and denitrification. The use of canopy sensors for making in-season N fertilizer applications has been proven effective in matching plant N requirements with periods of rapid N uptake (V7-V11), reducing the amount of N lost to these processes. However, N recommendation algorithms used in conjunction with canopy sensor measurements have not proven accurate in many fields of the U.S. Cornbelt, resulting in... , N.R. Kitchen, J. Camberato, P.R. Carter, R.B. Ferguson, F.G. Fernandez, D.W. Franzen, F.G. Fernandez, E.D. Nafziger, C.J. Ransom, , J. Shanahan, G.M. Bean |
40. Determining Cropping System and Topsoil Depth Effects on Phosphorus and Potassium Nutrient DynamicsUnderstanding the effects of fertilizer addition and crop removal on long-term change in soil test phosphorus (STP) and soil test potassium (STK) is crucial for maximizing the use of grower inputs on claypan soils. Due to variable topsoil depth, nutrient supply from subsoils, and crop removal across fields, accurate P and K fertilizer management can be challenging. Current Missouri fertilizer recommendations rely on a single buffering capacity for all soils throughout the state for P, and are only... |
41. Evaluation of Phosphorus and Potassium Fertilization on Corn and Soybean Yields and Soil Test Levels in OhioThe most recent fertilizer phosphorus (P) and potassium (K) recommendations for corn and soybean grown in Ohio were established in the mid-90s and research is required to verify the appropriateness of these recommendations after 20 years. In this study, corn and soybean rotations were established and maintained at three sites from 2006 to 2014 and fertilizer P and K were applied at 1) zero rates, 2) estimated nutrient removal rates and 3) twice the estimated nutrient removal rates for each rotation.... |
42. Topsoil Depth Influences Switchgrass Nitrogen Managment on Claypan SoilsSwitchgrass (Panicum virgatum L.) is an attractive forage or bioenergy crop option for eroded portions of claypan landscapes where grain crop production is marginally profitable. Topsoil depth to the claypan can vary widely within fields and little information exists on the impacts of the topsoil depth on nitrogen (N) management of switchgrass. Therefore, a study was initiated in 2009 at University of Missouri South Farm located near Columbia, MO on a site known as Soil Productivity Assessment for... |
43. Nitrogen Management: Unraveling the Effect of Timing and FormImprovement of nitrogen use efficiency by co rn production would decrease the potential for nitrogen loss into the environment. A study ha s been conducted in Ames, Iowa on 16 different forms and rates of nitrogen in both a continuous corn and corn-soybean production systems. There were differences among treatments; howeve r, the most consistent treatment was the SuperU applied as a 150 lb A -1 preplant or as 50 lb A-1 preplant and 100 lb A-1 sidedress and UAN with Agrotain adde d to both the 50... |
44. Switchgrass Response to Nitrogen: Trade-offs between Quantity and QualityIn 2009 and 2010, a study was conducted at four loca tions in southwest Wisconsin to determine optimal nitrogen (N) fertilizer rates and harvest timings for switchgrass quantity and quality. The study was conducted as a randomized complete bloc k, split plot design with five main plot treatments (0, 56, 112, 168, and 224 kg ha -1 of N) and three split plot treatments (mid-fall, late- fall, and early spring harvest). Dry matter (D M) yields increased between 2009 and 2010 and were most often maximized... |
45. Soybean foliar manganese recommendations on chronically Mn deficient soils.Soil Mn availability decreases with increasing pH and organic matter concentrations, leading to seasonal Mn deficiency symptoms in soybeans pr oduced on these soils. In Michigan, high pH conditions are often found in alluvial calcareous lakebed soils where conditions lead to low Mn solubility. High organic matter co ncentrations in organic soils reduce Mn availability due to formation of unavailable chelated Mn 2+ compounds and organic complexes in the soil. While Mn deficiencies on lakebed soils... |
46. Nitrogen Recalibration for Spring Wheat and Durum in North DakotaNorth Dakota will begin using new fertilizer r ecommendations beginning Dec. 1, 2009. Previous recommendations required a yield guess by growers with no rega rd to economics of nitrogen application. The new recommendations recogni ze different N response curves with yield and grain protein within three state agri-climatology zones. The reco mmendations use the "return to N" method, which vary the N recommendation based on crop price and N costs. The resulting rate is adjusted based on... D. Franzen, G. Endres, J. Lukach, R. Ashley, J. Staricka, K. Mckay |
47. What are the Benefits of Canopy Sensing for Variable-Rate Nitrogen Corn Fertilization?Canopy reflectance sensing for assessing crop N health has been proposed as a technology on which to base top-dress variable-rate N applicat ion. The objective of this research in Missouri was to evaluate the economic a nd environmental benefit of activ e-light crop-canopy reflectance sensors for corn N rate decisions. A total of 16 field-scale experiments were conducted over four seasons (2004-2007) in three major soil areas. Mu ltiple blocks of randomized N rate response plots traversed the length... |
48. Chloride Fertilization on Wheat, Corn, and Grain SorghumResearch in the Pacific Northwest and the Northern Great Plains has documented positive cereal grain responses to chloride (CI) fertilization. Field research was conducted in Kansas evaluating CI fertilization on winter wheat, corn, and grain sorghum. Chloride fertilization consistently and significantly increased plant CI concentrations in all crops. Chloride fertilization increased grain yields or one or more winter wheat cultivars at 3 of 4 sites. The most dramatic yield increases were at the... |
49. Nitrogen benefits when interseeding red clover into continuous cornInformation 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 |
50. Nitrogen Application, Biological N Fixation, and N UptakePrevious collaborative research in the Midwest has shown that there is likely little to no need of N for soybean, except under certain conditions (such as when low soil moisture limits N fixation, or when low initial soil nitrate-N limits overall N availability). However, none of the site-years used in this synthesis analysis were on sandy soils. Because sandy soils supply little nitrate-N, the potential impact of N on crop yield is greater in sandy environments than on silt loam soils. However,... A.M. Walters, M.D. Ruark, J.M. Gaska, C. Zegler, S.P. Conley |
51. Integrating Management Zones and Canopy Sensing for Improved Nitrogen Recommendation AlgorithmsActive 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 |
52. Comparison of Ground-Based Active Crop Canopy Sensor and Aerial Passive Crop Canopy Sensor for In-Season Nitrogen ManagementCrop 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 |
53. The Effect of Agricultural Management Practices on Labile Soil Carbon and Nitrogen in WisconsinAmid ever-increasing enthusiasm for soil health there remains uncertainty about how best to measure it, to interpret the results, and to adapt agricultural management accordingly. One factor of particular interest to farmers is the capacity of a soil to mineralize organic matter, making nutrients available to crops. This research takes a survey-based approach to identify how labile carbon (C) and nitrogen (N) – as permanganate oxidizable carbon (POxC), potentially mineralizable carbon (PMC)... G. Richardson, M. Ruark, E. Silva, M. Chawner, E. Olson, A. Radatz, C. Zegler |
54. Corn Tissue Nutrient Concentration Related to Soil Fertility LevelsSoil health metrics, such as active carbon or soil respiration, may be important factors influencing corn nutrient uptake. The push for increasing soil health has promoted the question of how soil health and soil fertility interact. This research determined how different soil health metrics impact early-season corn tissue potassium (K), sulfur (S), or phosphorus (P) nutrient content. Research conducted in 2019 on 35 producer Missouri fields encompassed many soil types and management practices.... M.B. Henry, N.R. Kitchen, K.S. Veum, J.D. Svedin |
55. Nitrogen Timing Fertilization Strategies for Winter Wheat in WisconsinEconomically optimum winter wheat (Triticum aestivum L.) production relies on effective N application rate and timing. Previous research in Wisconsin indicates a need to better understand winter wheat response to N rate and application timing for growing conditions specific to the state. This study evaluated the effect of N application timing on yield, economic optimum N rate (EONR), agronomic N use efficiency (NUE), and profitability. A three-year study was conducted at three locations... J.D. Jones, C.A. Laboski, T.W. Andraski |
56. Practical Farmers of Iowa On-farm Research ProgramPractical Farmers of Iowa (PFI) has been leading and conducting on-farm research since 1987. The organization has staff scientists to help design experiments based on questions from participating farmers. Farmers are cooperators in research and they often collaborate with other farmers on the same project. Ideas for projects are considered at the annual Cooperators’ Meeting in December each year. Cooperators describe what was done on their farm, why they did it, and what they found. They... S. Gailans |
57. Does Nitrogen Management in Winter Wheat Affects Its Yield and Nitrate-N Leaching in a Wheat-Soybean Double Cropping System?Conventional corn (Zea mays L.)-soybean (Glycine max L.) rotation contributes to nitrate-N and phosphate leaching to waterbodies causing water quality concerns. Two strategies that could minimize N and P losses include (i) incorporating winter rye (Secale cereale L.) (WR) as a cover crop to capture residual nutrients or (ii) intensifying the corn-soybean rotation with winter wheat (WW) (Triticum aestivum L.) (Double cropping). Double cropping WW at a right N... A. Sadeghpour, O. Ola, O. Guzel, K.L. Gage, K. Williard, J. Schoonover, S. Mueller |