Download the
Conference Proceedings

 
Get your copy of the 2024 North Central Soil Fertility Conference proceedings today! Download the PDF file and view all of the available proceedings.
NCSFC Proceedings 2024.pdf

Proceedings

Find matching any: Reset
Wayment, J
Chessman, D
Walker, Z
Wolthuizen, J
McDaniel, M
Taylor, R.K
Nielsen, R
Warren, J.J
Flaten, D
Edwards, C.L
Nafziger, E
Vasey, E
Hankinson, M
Teeter, A
Clay, D
Krill, T.L
Oltmans, R
Krull, D
Eckert, D.J
Wilhelm, W.W
Kravchenko, A.N
Add filter to result:
Authors
Hornaday, C
Camberato, J
Nielsen, R
Krienke, B
Ferguson, R
Luck, J
Thompson, L
Parrish, J
Mueller, N
Mieno, T
Crowther, J
Shaver, T
Ingram, T
Krull, D
Glewen, K
Lee, J
Camberato, J
Nielsen, R
Moser, M
Nielsen, R
Camberato, J
Shafer, M
Camberato, J
Carter, P
Ferguson, R
Fernandez, F
Franzen, D
Kitchen, N
Laboski, C
Nafziger, E
Nielsen, R
Sawyer, J
Shanahan, J
Walker, Z
Yost, M
Russelle, M
Venterea, R
Coulter, J
Mallarino, A
Lauer, J
Bardella, G
Flaten, D
Lawley, Y
Heard, J
Lange, D
Grant, C
Edwards, C.L
Ruiz Diaz, D.A
Gutierrez, M.N
Ruiz Diaz, D.A
Edwards, C.L
Rosa, A.T
Rosa, A.T
Ruiz Diaz, D.A
Gutierrez, M.N
Edwards, C.L
Gardner, T
Lorence, A
Eckert, D.J
Hopkins, D
Vasey, E
Eckert, D.J
Reed, K.A
Eckert, D.J
Eckert, D.J
Ritchie, K.B
Hoeft, R.G
Nafziger, E.D
Gonzini, L.C
Warren, J.J
Krill, T.L
Ritchie, K.B
Hoeft, R.G
Gonzini, L.C
Warren, J.J
Nafziger, E.D
Hoeft, R.G
Nafziger, E.D
Mulvaney, R.L
Gonzini, L.C
Warren, J.J
DeJoia, A.J
Young, K
Schmidt, J.P
Taylor, R.K
Hoeft, R.G
Nafziger, E.D
Gonzini, L.C
Warren, J.J
Mathesius, J.J
Daverede, I.C
Kravchenko, A.N
Hoeft, R.G
Nafziger, E.D
Bullock, D.G
Warren, J.J
Gonzini, L.C
Guebert, K.S
Hoeft, R.G
Nafziger, E.D
Adee, E.A
Dunker, R.E
Paul, L.E
Gonzini, L.C
Warren, J.J
Varvel, G.E
Schepers, J.S
Wilhelm, W.W
Shanahan, J.F
Francis, D.D
Shanahan, J.F
Wilhelm, W.W
Wienhold, B.J
Edwards, C.L
Diaz, D.R
Mengel, D
Sanyal, D
Wolthuizen, J
Karki, D
Clark, J
Bly, A
Sanyal, D
Rahhal, A
Bielenberg, H
Wolthuizen, J
Clark, J
Bly, A
McGlinch, G
Lindsey, L
Shrestha, R
Hankinson, M
Chessman, D
Bourns, M
Flaten, D
Heard, J
Bartley, G
McDaniel, M
Walters, D
Bundy, L
Laboski, C
Scharf, P
Drijber, R
Horwath, W
Sawyer, J
Sawyer, J
Castellano, M
Oltmans, R
Mallarino, A
Teeter, A
Andraski, T
Laboski, C
Preza-Fontes, G
Nafziger, E
Christianson, L
Pittelkow, C
Rahhal, A
Sanyal, D
Wolthuizen, J
Bielenberg, H
Clark, J
Bly, A
Bielenberg, H
Clark, J
Bly, A
Sanyal, D
Wolthuizen, J
Rahhal, A
Wayment, J
Fernandez, F.G
Sharma, V
Bhattarai, D
Clark, J
Clay, D
Ahlersmeyer, A
Clark, J.D
Clay, D
Osterloh, K
Nafziger, E
Sawyer, J
Ahlersmeyer, A
Clark, J
Osterloh, K
Clay, D
Topics
Positive and negatives of cover crops
Crop genetic and soil fertility interactions
State Report
N Management with Cover Crops
Soil Health Metrics
General
Invited
Graduate Award Student Poster
Type
Oral
Poster
Year
2016
2015
2014
1985
1986
1989
1990
1995
1996
1997
1998
1999
2002
2006
2008
2013
2019
2017
2018
2020
2021
2022
Home » Authors » Results

Authors

Filter results42 paper(s) found.

1. Educational Applications of Digitized Soil Surveys

The North Dakota Agricultural Experiment Station Soil Survey of McHenry County Organized Irrigation Districts is approaching publication and represents a first for soil survey in North Dakota. The decision was made to digitize the soil maps to facilitate acreage tabulations and improve methods of generating soil interpretations. While the digitization procedure is costly in terms of start-up labor (programming) and data entry, the benefits allow more flexibility than conventional soil surveys. The...

2. Rye Cover Crops in No-till Corn Production

Field studies have been conducted for several years in Ohio to determine the effects of including a ry.e cover crop in no-till production situations. These studies were conducted at two locations, on a moderately well drained Canfield silt loam at Wooster, and a very poorly drained, but tiled, Hoytville silty clay at Hoytville. At Wooster, no-till corn was planted into corn or soybean residue, with or without a fall-seeded rye cover crop (2 bu/A seeding rate). Individual plots received 200 lb N/A...

3. Managing UAN Solutions in No-tillage Corn

Studies in many states over the past several years have indicated some type of inefficiency associated with broacasting N (nitrogen) as UAN (urea-anmnium nitrate) solution in no-tillage corn production situa- tions. Broadcasting UAN has often given lower yields when ccmpared to injected anhydrous amnonia or broadcast amnonium nitrate. Several theories have been proposed to account for this inefficiency, including volatilization of the urea canponent of the UAN, inmobilization of N during breakdown...

4. Nitrogen Source Affects Manganese Nutrition of No Till Corn

A study evaluating response of no-till continuous corn to different rates of N as injected anhydrous ammonia and broadcasted urea-ammonium nitrate solution (UAN) was conducted on a Canfield silt loam near Wooster, Ohio. Repeated use of anhydrous ammonia on this naturally acid soil resulted in relatively large concentrations of Mn (often > 200 ug/g) in corn plant ear leaves at silking. Ear leaf Mn concentrations were less when UAN was used. For both N source treatments, ear leaf Mn concentrations...

5. Ammonium Thiosulfate Effects on Corn Production

Ammonium thiosulfate ((NH,),S,O,, ATS) and urea-ammonium nitrate solution (UAN) were applied in different combinations to corn grown in five site-year studies to assess any effects of ATS on corn performance. Ammonium sulfate ((NH4),S04, AS) was included in three of these comparisons as an alternate sulfur (S) treatment. Adding ATS to UAN increased corn yield in one comparison, decreased it in another and had no effect on yield in others. Adding AS had no effect on corn yield. Neither S material...

6. Nutrient Management and Starter Fertilizer for No-till Corn

No-till corn acreage has steadily increased in Illinois. No-till presents unique problems of nutrient stratification, increased surface residue, and cool, wet soils which may influence nutrient availability. Two experiments were initiated in 1993 at 4 locations to evaluate the response of no-till corn to: 1) primary N applications of anhydrous ammonia preplant, UAN broadcast preplant, and ammonia sidedressed at V6; 2) starter fertilizers with factorial combinations of N, P, and K banded 2 inches...

7. Yield Monitoring- The Beginning or the End

As site specific management or precision farming gains acceptance with the agricultural producer, the question remains: '.Where do I begin?". As technology creates and makes available new machines for the site specific environment: ''How do they fit into the picture?". As the yield monitor has become the most popular and accepted of these technological innovations for the agricultural producer, what role does it play in the sitc specific management concept? What is site specific management and where...

8. Effect of Time and Rate of N Application on N use Efficiency and Surface Water Contamination with Nitrates

Nitrate levels in excess of the public health standard of 10 mg N/1 in public water supplies along - with concern about hypoxia in the Gulf of Mexico have drawn renewed interest to improving fertilizer N use efficiency. Prior research has indicated that some farmers may be unkaowingly contributing to these problems. The objectives of this research were to: determine the effect of rate and time of N application on nitrate-N concentrations in water from tile lines and to evaluate the effect of previous...

9. Nitrogen Management in Irrigated Corn Using Remotely-Sensed Imagery and Small-Plot Experiments

Nitrogen management for irrigated corn (Zea mays L.) grown along the Arkansas River Valley in Kansas is a concern due to the hig&ly leachable soils and high water tables (ranging fiom 10-50 A). Irrigated corn usually requires a high input of N fertilizer to achieve maximum yields, and most farmers in this area have been applying a uniform rate of nitrogen across their fields every growing season based on the following KSU N recommendation. N Rec = [YG * 1.35 lbs bu-'1 STA - PCA - PYM - PNST N Rec-nitrogen...

10. Effect of Time of N Application for Corn

The economic benefit associated with the application of N fertilizers for corn has been known for over 5 decades. As a result, over 99 % of the farmers in Illinois apply N fertilizers when corn is grown. Unlike phosphorus and potassium, there is no good soil test to predict the amount of N needed, instead, farmers use a factor times yield potential with appropriate credits for legume and other N sources to set N rates. While this works well over a number of years, there are years when less N will...

11. Phosphorus Runoff From Incorporated and Surface-Applied Fertilizer and Manure

Continued inputs of fertiher and manure in excess of crop requirements have led to a build-up of soil phosphorus (I?) levels, creating an environmental rather than agronomic concern (Sharpley et al., 1994). The objective of this study was to evaluate the effects of soil test P level, source of P amendments, tillage, and manure application method on P runoff from agricultural soils. The treatments consisted of swine manure surface applied and injected at rates of 29 and 59 Ib acre-' of P, and triple...

12. Strip till Nitrogen Placement, and Starter Fertilizer Effects on Corn Growth and Yield

Strip tillage, a system where residue is removed and small ridges are formed in the fall in the position of next year's rows, has become an increasingly popular alternative to 0-till for corn in Illinois. Over three years and eight environments in Central and Northern Illinois, tillage had no effect on grain yield: conventional tillage, strip tillage, and 0-till produced 1 1.67, 11.67, 1 1.57 Mg/ha, respectively. There were also no differences in yield due to N timing, N placement, or starter fertilizer....

13. In-Season Nitrogen Recommendations for Corn

Making fertilizer N recommendations involves a great deal of guess work and uncertainty because much, essentially all, of the fertilizer N is applied before the crop is planted and the amount is based on estimated crop use from historical data. In addition, producers, consultants, and fertilizer dealers try to anticipate how much N might be lost because of untimely or excess precipitation or how much additional N might be required if the weather conditions are favorable. Sidedress and in-season...

14. Crop Residue Removal Effects on Soil Properties

Three large challenges facing mankind are the n eed to feed a rapidly growing population, increasing concentration of greenhouse gases in the atmosphere, and reliance on fossil fuels. Expectations from agriculture include produ ction of food and fiber to meet demands, management of agricultural systems to sequester carbon and redu ce emission of other greenhouse gases, and provision of feedstock for a rapidly expanding biofuels industry. Some discussions involving use of crop residue for biofuel...

15. Corn and Soybean Response to Phosphorus Placement under Minimum Tillage System

Producers often question the need for better fertilizer placement methods in reduced tillage systems. The objective of this study was to evaluate the effects of different placements and rates of phosphorus (P) fertilizer for corn (Zea mays) and soybean (Glycine max). The study was conducted at 3 locations from 2005 to 2012 (8 years). This paper presents results from one irrigated location. Tillage system was strip till before planting corn; and soybean was planted without previous tillage. Fertilizer...

16. Do Soil Nitrogen Tests Relate to Nitrogen Mineralization in First-year Corn Following Alfalfa?

Corn (Zea mays L.) is the most frequent first-year crop grown following alfalfa (Medicago sativa L.) in the Upper Midwest. In the majority of cases, first-year corn does not respond to fertilizer N, but sometimes large amounts are needed to optimize yield. The pre-sidedress and Illinois soil N tests (PSNT and ISNT, respectively) are early-season tests used to predict corn yield response to fertilizer N. These tests measure specific fractions of soil N and define a critical concentration to separate...

17. 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....

18. Evaluating the Interaction between Chelated Fe Source and Placement on Phosphorus Availability in Soybean

In agriculture, chelating agents are used to supplement micronutrients, such as iron (Fe). However, little research has been conducted on a field scale to evaluate chelating agent effects on phosphorus (P) uptake. The objectives of this study were to evaluate four commercially available chelated Fe sources on early soybean growth and nitrogen (N), P, and potassium (K) uptake. The study was conducted at two locations, and the experimental design was a randomized complete block with four replications...

19. Evaluation of Secondary and Micronutrient for Soybean Production in Kansas

Secondary and micronutrients are being increasingly studied for their potential to contribute to yield increase. The objective of this study was to evaluate soybean response to secondary and micronutrient fertilizer application to maximize yields. A randomized complete block design was employed with four replications, at five locations during 2013 and five locations in 2014. Treatments consisted of micronutrient fertilizer as individual nutrient for B, Cu, Mn, S and Zn, in addition to a mix of these...

20. Fertilizer Placement and Tillage Interaction in Corn and Soybean Production

Different tillage systems can affect the availability of phosphorus (P) in the soil. The objective of this study was to evaluate the effects and interaction of fertilizer placement, tillage, and varieties/hybrids for corn and soybean. The experiment was established at two locations in Kansas in 2014. The experimental design was a factorial in a randomized complete block with four replications. Three fertilizer treatments were combined with two tillage systems and two varieties/hybrids of soybean...

21. Response of Minimum-till Corn to Starter Fertilizer and ACA

Starter fertilizer containing N and P often increases grain yield under no-till management. but yield responses to starter have riot been consistently observed under conventional tillage. Experiments were established in 1996 and 1997 at six sites varying in latitude, soil type. fertility, and crop rotation to evaluate the effect of starter fertilizers on corn grown under high-residue minimum-till systems. In one experiment, a factorial combination of 3 N. 2 P, and 2 K rates placed in a 2x2 band was...

22. Cover Crops Influence Soil Health and Nutrient Cycling in a Multi-Location Study in South Dakota

Soil without living roots potentially loses mobile nutrients and retains excess water. Unprotected soil degradation and erosion enable the loss of carbon and nutrient rich top soil. Cover crops provide armor for the soil protecting from carbon and nutrient loss. Cover crop blends may influence soil health parameters and nutrient cycling. This multi-locational study depicts the influence of cover crop species blends with varying grass and broadleaf concentrations on established soil-health indicators... D. Sanyal, J. Wolthuizen, D. Karki, J. Clark, A. Bly

23. Do cover crops improve soil health and enhance nutrient availability to cash crops?

Bare soils are prone to erosion and lose soluble nutrients. Cover crops provide protection to the soil against erosion and nutrient loss. We hypothesized that the cover crops should uptake available nutrients from the soils in the fall when there is no cash crop, assimilate the nutrients in their tissues, and in the following spring, should release the nutrients back to the soil during the next cash crop growing season. In our study, we are quantifying the nutrients taken up by the cover crops... D. Sanyal, A. Rahhal, H. Bielenberg, J. Wolthuizen, J. Clark, A. Bly

24. Optimizing Nitrogen Rate to Maximize Winter Malting Barley Grain Yield While Meeting Protein

Winter malting barley (Hordeum vulgare) acreage is increasing across Ohio due to demand from the local craft brewing industry; however, grain used for this market must pass specific quality requirements. The objective of this study was to identify optimum spring nitrogen rates for winter malting barley that maximize yield while meeting protein requirements. Small plot trials were conducted at three locations in Ohio: Northwest Agriculture Research Station (NWARS) in Custar, Western Agriculture... G. Mcglinch, L. Lindsey, R. Shrestha, M. Hankinson

25. Soybean Response to Potassium Fertility and Fertilizer in Manitoba

Soybean acres have increased greatly in Manitoba in recent years, now occupying more than 25% of the province’s annual crop land. Potassium removal by soybean is greater than any other crop grown in Manitoba (1.1 – 1.4 lb K2O/bu). This large removal, accompanied by the large and rapid expansion in soybean acres, has contributed to an increase in province-wide potassium removal rates and likely explains the increase in incidence of potassium deficiency symptoms reported in recent years.... M. Bourns, D. Flaten, J. Heard, G. Bartley

26. A Combination of Soil Incubation and Chemical Extraction Tests Best Predicts Corn Yield Response to Fertilizer Nitrogen

Soil tests in general have served a critical role in the field of soil fertility for over half a century, and have helped to increase crop productivity and promote more efficient use of fertilizers on farms. However, N soil tests have limitations and chemical extraction tests have not predicted well the potentially mineralizable N supplied to corn over a growing season. Thus, these tests often do not accurately predict a corn’s yield response to fertilizer N. We explored 30 soil tests for... M. Mcdaniel, D. Walters, L. Bundy, C. Laboski, P. Scharf, R. Drijber, W. Horwath, J. Sawyer, J. Sawyer, M. Castellano

27. Effects of Sampling Time and Extraction Method on Soil-Test and Nonexchangeable Potassium in Iowa Soils

More research is needed to better understand K cycling and high short-term temporal soil-test K (STK) variation. The objective of this research was to study soil-test K and nonexchangeable K pools across Iowa soils managed with corn-soybean rotations as affected by K application rates, soil properties, parent materials, and time of sampling. Three-year field trials that included a control and several broadcast K fertilizer rates were conducted at 35 Iowa sites. Soil samples (6-inch depth) were... R. Oltmans, A. Mallarino

28. Can Nitrapyrin and Cover Crop Improve Fall Dairy Slurry N Availability to Corn?

Fall applications of manure have the potential for high nitrogen (N) losses. Cereal/grass cover crops have been shown to take up fall applied N. Similarly, using nitrapyrin (Instinct®) has been shown to prevent loss of fall applied N. No studies have been conducted to evaluate combining these tools to prevent N loss. This experiment was performed in 2016 and 2017 on a well-drained and somewhat poorly drained silt loam soils. This study was conducted to determine if using Instinct® and... A. Teeter, T. Andraski, C. Laboski

29. The Importance of Soil Health and the Efforts of NRCS

Since its inception in 1932, USDA-NRCS has worked with agricultural producers and landowners to address natural resource concerns, and improve long-term productivity on the nation’s private working lands. The mission of the agency is accomplished primarily through local field staff who provide technical assistance, and work with interested farmers and ranchers to develop conservation plans that improve identified resource concerns. In addition to site-specific technical recommendations,... D. Chessman

30. Response of Continuous Corn to Varying Rates and Placements of Starter Fertilizer

Previous research has shown that starter fertilizer, a small amount of fertilizer placed with or near the seed at planting, often accelerates early season growth and increases biomass production, but does not always increase grain yield in corn (Zea mays L.). Our objective was to evaluate the effects of starter fertilizer on crop growth and development, as well as grain yield and moisture in continuous corn cropping systems. Treatments consisted of no fertilizer applied at planting (Control),... C. Hornaday, J. Camberato, R. Nielsen

31. Project Sense: Sensors for the Efficient Use of Nitrogen and Stewardship of the Environment. An On-Farm Research Effort to Increase Adoption of Sensor Based N Management

Low nitrogen use efficiency (NUE) has been attributed to several factors including asynchrony between nitrogen (N) fertilizer application, crop demand, and spatial variability (Shanahan et al., 2008). Sidedress applied N synchronizes crop uptake demand for N, but does not address the spatial and temporal variability that exists in a field year to year. Active crop canopy sensors provide an ability to monitor and respond to spatial and temporal N variability for a given field. A three-year project,... B. Krienke, R. Ferguson, J. Luck, L. Thompson, J. Parrish, N. Mueller, T. Mieno, J. Crowther, T. Shaver, T. Ingram, D. Krull, K. Glewen

32. Starter Fertilizer Slows the Movement of Corn Roots Across the Row

Applications of starter fertilizer may alter the root morphology of young developing plants by causing lateral roots to proliferate when the root system enters the highly concentrated fertilizer band. This may affect the timing of root movement across the row when starter fertilizer is used. The timing of root movement across the row was determined by placing 20 12-inch-long perforated cylinders vertically in the soil at the V2 leaf stage. The cylinders were placed approximately every 15”... J. Lee, J. Camberato, R. Nielsen

33. Residual Effects of Nitrogen Fertilization on Soil Nitrogen Pools and Corn Growth

Nitrogen (N) fertilization of corn (Zea mays L.) may increase, decrease, or not affect the N supplying capacity of the soil. Six field-scale corn N rate trials were established in corn-soybean rotations in diverse soil types across Indiana. Six N rates ranging from about 25 to 270 lb N ac-1 were replicated 4 to 6 times at each site and re-applied to the same plots for each of four corn crops. In the fifth corn season, 2015, half of the replications at each location were supplied... M. Moser, R. Nielsen, J. Camberato

34. Variation in Internal N Efficiency of Corn and Impact on Yield-Goal Based N Recommendations

Internal N efficiency (IE) is defined as bushels per acre (GY) produced per pound of N per acre (PMN) in the plant at physiological maturity (R6). Internal N efficiency defines the required amount of plant N content at R6 in a yield-goal based N rate recommendations (currently used in 30 U.S. states) and several commercial N recommendation models. Commonly IE is assumed to be constant at an approximate value of 0.8 bu lb-N-1 in yield-goal based recommendations. Our research objective was... M. Shafer, J. Camberato, P. Carter, R. Ferguson, F. Fernandez, D. Franzen, N. Kitchen, C. Laboski, E. Nafziger, R. Nielsen, J. Sawyer, J. Shanahan

35. Relationship of in-season soil nitrogen concentration with corn yield and potential nitrogen losses

Modeled or measured soil mineral N (SMN) levels during the corn growing season have been used to set sidedress N rates, but there has been little research linking SMN levels at different growth stages to yield to help guide this process. The degree to which SMN level influences the risk of N losses is also not known. Data from 32 site-years of field experiments in Illinois (2015–2018) that included 12 combinations of N fertilizer rate, timing, and source, were used to evaluate... G. Preza-fontes, E. Nafziger, L. Christianson, C. Pittelkow

36. Cover crops nutrients uptake did not cause yield loss in corn

Bare soils are susceptible to erosion and nutrient loss. Cover crops and residues provide physical protection against erosion and nutrient loss, and improve nutrient cycling as well as biodiversity. We hypothesized that cover crops store available nutrients from the soil in the fall and release them the next spring for the next cash crop, minimizing potential nutrients loss with no adverse effect on cash crop yield. A four site-year study throughout South Dakota was conducted to compare...

37. Can Cover Crops Help to Improve Soil Health While Having a Positive Effect on Corn Grain Yield?

Cover crops have recently gained attention in the U.S. Mid-west because of their potential to increase soil organic matter and improve overall soil health. There is some concern however, that cover crops may negatively impact corn grain yield. This study was conducted to determine the effects that different cover crop mixtures have on soil health measurements and corn grain yield at increasing nitrogen rates. Cover crops were planted in the fall as a dominantly grass mixture, dominantly...

38. Can Kura Clover and Winter Rye Covers Mitigate Nitrate Leaching In Irrigated Sands?

Cover crops are gaining more popularity as a mitigation tool to prevent nitrate (NO3--N) leaching from the corn (Zea mays L.) and soybean [Glycine max (L.) merr.] fields of Minnesota. Leaching of NO3--N is not only a monetary loss for growers, but also results in groundwater contamination.  Winter rye (Secale cereale), a commonly grown cover crop in Minnesota and kura clover (Trifolium ambiguum), a less...

39. No-till corn nitrogen recommendation using precision soil management practices

In long-term no-till fields, South Dakota (SD) farmers reported a reduced fertilizer-nitrogen (N) requirement compared to conventional tillage to obtain optimum corn yield. Reduced fertilizer recommendation may be due to improved soil health resulting from increasing soil organic matter, higher soil microbial activities, and improved water and nutrient use efficiency over the years the no-till system is used. However, the impact of soil health measurements on fertilizer-N requirement has not been... D. Bhattarai, J. Clark, D. Clay

40. Implications of Clay Mineral Analysis for Improved Calibration of Corn Potassium Fertilizer Recommendations

Eastern South Dakota has seen an increase in soil potassium (K) deficiencies. To correct those deficiencies and avoid yield reductions, corn producers rely on accurate K fertilizer recommendations (KFRs). Among the various parameters used to estimate a KFR, clay mineralogy has significant potential to increase KFR accuracy. The study has two objectives: first, to determine the relationships among clay mineralogy, K uptake by corn, and KFRs, and second, to calibrate KFRs in South Dakota to incorporate... A. Ahlersmeyer, J. Clark, D. Clay, K. Osterloh

41. The MRTN Approach: Past, Present, and Future

The method of using crop N response data assimilation, now called the “MRTN approach”, was conceived at a September, 2004 meeting in Bettendorf, Iowa of scientists from several Corn Belt states. This meeting was prompted by findings in field trials that showed substantially lower optimum N rates than those based on using corn yield goal to predict crop N needs; most also showed no correlation between EONR and yield at EONR across trials. The MRTN method is straightforward: yield data... E. Nafziger, J. Sawyer

42. Consideration of Clay Mineralogy for Enhanced Prediction of Optimal Corn Potassium Fertilizer Rates

Properly calibrated potassium (K) fertilizer recommendations (KFRs) are critical for improving crop yields and maintaining environmental stewardship. Recent innovations in soil and crop management suggest that certain soil factors, including clay mineralogy, can be used to predict optimal K requirements in corn. The objectives of this study include 1) correlate soil K levels to corn yield, 2) calibrate KFRs with clay mineralogy data, and 3) determine the relationships among clay mineralogy, K... A. Ahlersmeyer, J. Clark, K. Osterloh, D. Clay