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Moran Duran, S
Rogers, C
Lauriault, L
Koenig, R
Spackman, J.A
Sainju, U
Moody, J
McGuire, A
Reid, C
Stockert, C
Neuman, J
Sannar, R.E
Blaylock, A
Creech, E
Shafer, S
Snyder, E
Southard, R
Jayawardena, D.M
Geary, B.T
Love, S
Massey, M
Johnston, W
Nunez, H
Potter, M
Stapley, S
Sannar, L.K
Kleinman, P
Lambert, A.M
Koeshall, S
Miller, B
Price, S
Ohm, J
Tindall, T
Cartwright, A
Mikkelsen, R
Pattnaik, R
Leytem, A
Hoefer, B
Penton, C
Golob, C
Light, S
Ghimire, R
Stark, J
Schierer, R
Moore, A
Julian, J
Ellickson, S
Ransom, C
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Authors
Evans, C
Moore, A
Sullivan, D
Fernandez, F.G
Spackman, J.A
Cole, D.L
Heidenreich, D.T
Stapley, S.H
Lambert, A.M
Buck, R.L
Hopkins, B.G
Deakin, J.W
Potter, M
Cartwright, A
Hortin, J
Sparks, D
McLean, J.E
Britt, D.W
Anderson, A.J
Jacobson, A.R
Ghimire, R
Salehin, S
Jeliazkova, E
Moore, A
Spring, J
Wilson, T
Geary, B.T
Fahning, S.R
Hopkins, B.G
Stapley, S
Hopkins, B
Moore, A
Gent, D
Verhoeven, B
Walsh, O.S
Shafian, S
Jayawardena, D.M
Walsh, O.S
Jayawardena, D.M
Rogers, C
Thurgood, G
Dari, B
Marshall, J
Walsh, O.S
Schroeder, K
Loomis, G
Verhoeven, B
Moore, A
Sullivan, D
Gonzalez-Mateu, M
Koenig, R
Proctor, C
Johnston, W
Golob, C
Koenig, R
G. Davis, J
Ippolito, J
Massey, M
Sheffield, R
Mikkelsen, R
Yost, R
Pattnaik, R
Porter, G
Norton, J
Habteselassie, M
Stark, J
Miller, B
Ross, A
Saint Pierre, C
Peterson, C
Ohm, J
Verhoeven, M
Larson, M
Hoefer, B
G. Davis, J
Schierer, R
Zumbrunnen, J
Smart, D
Whiting, M
Stockert, C
Stark, J
Love, S
McIntosh, C
Tindall, T
Valencia-Gica, R
Yost, R
Porter, G
Pattnaik, R
Walworth, J
Pond, A
Nunez, H
Wood, B
Kilby, M
Grossl, P
Koenig, R
Jones, C
Trolove, S
Moore, A
Alva, A
Collins, H
Boydston, R
Andrews, N
Sullivan, D
Julian, J
Pool, K
Hopkins, B
Webb, B
Hill, M
Ransom, C
Lauriault, L
McGuire, A
Moore, A
Brown, B
Ippolito, J
Hines, S
de Haro Marti, M
Falen, C
Chahine, M
Fife, T
Norell, R
Tindall, T
Mooso, G
Pettygrove, S
O'Geen, T
Southard, R
Hopkins, B
Ransom, C
Lenssen, A
Sainju, U
Goosey, H
Snyder, E
Hatfield, P
Hopkins, B
Blair, T
Hill, M
Ransom, C
Deenik, J
Penton, C
Popp, B
Bruland, G
Engstrom, P
Mueller, J
Tiedje, J
Smith, R
Blaylock, A
Ellison, E
Sanchez, C
Ghimire, R
Norton, J
Moore, A
Moore, A
Satterwhite, M
Ippolito, J
Mooso, G
Tindall, T
Hettiarachchi, G
Hopkins, B
Ransom, C
Taysom, T
LeMonte, J
Hopkins, B
Sutton, L
Ransom, C
Blair, T
Moody, J
Manning, K
Bergsten, S
Blair, T
Ransom, C
Hosford, P
Svedin, J
Sutton, L
Winchester, A
Manning, K
Hopkins, T
Hopkins, B
Blaylock, A
Flynn, R
Heerema, R
Moran Duran, S
Leytem, A
Sullivan, D
Light, S
Horneck, D
Mooso, G
Tindall, T
Hopkins, B
Ransom, C
Ruth, M
Blair, T
Sutton, L
Bradshaw, D
Campbell, K
Hopkins, B
Blair, T
Selman, J
Ransom, C
Hopkins, T
Hopkins, B
Svedin, J
Ransom, C
Buss, J
Blair, T
Rogers, C
Shafer, S
Atoloye, I
Reeve, J
jacobson, A
Creech, E
De, M
Moore, A
Mikkelsen, R
Adeleke, K
Reeve, J
Creech, E
Atoloye, I
Evans, S
Hansen, N
Blaylock, A
Blaylock, A
Rogers, C
Dari, B
Neibling, H
Neuman, J
Sullivan, D
Moore, A
Pound, C
Yost, M
Creech, E
Cardon, G
Russell, K
Despain, D
Gale, J
Heaton, K
Kitchen, B
Pace, M
Price, S
Reid, C
Palmer, M
Nelson, M
Stapley, S
Buss, J
Hopkins, B
Clark, N
Lundy, M
Nelsen, T
Leinfelder-Miles, M
Light, S
Galdi, G
Getts, T
Mathesius, K
Yost, M
Baker, M
Gale, J
Creech, E
Cardon, G
Yost, M
Baker, M
Gale, J
Cardon, G
Creech, E
Sannar, L.K
Hopkins, B.G
Hopkins, T.J
Ellickson, S
Moore, A
Zemetra, R
Hagerty, C
Messman, C.H
Moore, A
Sullivan, T
Yost, M
Boren, D
Creech, E
Bugbee, B
Blaylock, A
Jones, C
Miller, P
Carr, P
Koeshall, S
Fordyce, S
Souza, J
Vetch, J
Moore, A
Leytem, A.B
Cox, A
Moore, A
Auld, R
Moore, A
Moore, J
Zhang, Y
Rogers, C
Moore, A
Ellickson, S
Rogers, C
Simpson, Z
Mott, J
Kleinman, P
Hopkins, B
Bell, G
Nelson, S.V
Sannar, R.E
Sannar, R.E
Bremer, E
Greer, K
Hopkins, B
Topics
Liming and Soil Acidity
Fertilizer Evaluations
Crop Nutrient Management
Nutrient Management of Horticultural Crops
Nutrient Management of Agronomic Crops
Organic Amendments, Cover Crops, and Soil Health
Sensors and Other Technologies for Nutrient Management
4R's for N, P, K, S
General
Environmental and Agricultural Nutrient Management
Invited Oral Presentation
Student Posters
Type
Oral
Poster
Year
2021
2007
2009
2011
2013
2015
2017
2019
2023
2025
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Filter results82 paper(s) found.

1. Evaluation of Lime Requirement Estimation Methods for Oregon Agricultural Soils

Soil testing labs in the Pacific Northwest are considering non-hazardous alternatives to the Shoemaker-McLean-Pratt (SMP) buffer method for lime requirement estimation (LRE). While alternative LRE methods have been adopted in other parts of the U.S., they have not been evaluated for Oregon soils.  The goal of this study was to evaluate several LRE methods for agricultural soils from western and eastern Oregon, applying the lime incubation method for actual lime requirement. Twenty-four acidic... C. Evans, A. Moore, D. Sullivan

2. 15Nitrogen Uptake and Use Efficiency in Corn in Response to Fertilizer Rate and Timing

Urea fertilizer applications at planting are becoming increasingly common for U.S. upper Midwest corn (Zea mays L.) production but wet spring conditions may result in significant nitrogen (N) fertilizer loss. Split-applications may avoid wet conditions and improve fertilizer uptake and use efficiency. Six field studies were performed to determine the effect of urea fertilizer rate and application timing on fertilizer-derived N (FDN) and soil-derived N (SDN) plant uptake over two consecutive... F. Fernandez, J. Spackman

3. New Hydroponic System for Testing Mineral Nutrient Deficiencies: Quinoa

Correlating plant tissue nutrient concentrations with visual symptoms is valuable in combating mineral nutrient deficiencies and toxicities. Major crops tend to have adequate information regarding nutrient concentrations and visual symptoms of deficiencies, but this is often lacking for minor crops, including quinoa (Chenopodium quinoa L.) Because nutrient concentrations can be easily controlled, hydroponics effectively demonstrate isolated specific nutrient related symptoms. However,... D.L. Cole, D.T. Heidenreich, S.H. Stapley, A.M. Lambert, R.L. Buck, B.G. Hopkins

4. Is Mitigation of Drought Stress By Zinc Oxide Nanoparticles Driven By a Nano-Specific Mechanism or Alleviation of Micronutrient Deficiency?

It has been reported that zinc oxide (ZnO) nanoparticles (NPs) can promote drought tolerance in crops when used as soil amendments. However, many of these experiments were conducted in Zn-deficient growth media with no comparison to currently available Zn fertilization methods, making it unclear if the benefits from adding ZnO NPs were caused by a nano-specifc mechanism or simply by the mitigation of a micronutrient deficiency. A review of the literature shows that of 12 published experiments... J.W. Deakin, M. Potter, A. Cartwright, J. Hortin, D. Sparks, J.E. Mclean, D.W. Britt, A.J. Anderson, A.R. Jacobson, L. Yen

5. Soil Organic Carbon and Nitrogen Dynamics Under Dryland Sorghum in New Mexico

Sorghum [Sorghum bicolor (L.) Moench] serves as a low-cost alternative to corn (Zea mays L.) in semi-arid regions of the world because of its high N and water use efficiencies. However, there has been a concern regarding N loss to the atmosphere as nitrous oxide (N2O) from semi-arid drylands. This study investigated various soil C and N components, including CO2 and N2O emissions, and crop yield with a dairy compost (13.5 Mg ha-1) and... R. Ghimire, S. Salehin

6. Evaluating Nutrient Uptake and Partitioning for Hybrid Carrot Seed Production in Central Oregon

Hybrid carrot seed production is prominent in Central Oregon, however plant nutrient uptake dynamics in this crop are not well understood. The aim of this research was to evaluate nutrient uptake and partitioning during the production cycle of a modern Nantes-type hybrid carrot. Trials were conducted in two commercial carrot seed production fields planted to ‘Nantes 969’. Below- and above-ground plant biomass was destructively sampled and separated into roots, tops, and umbels throughout... E. Jeliazkova, A. Moore, J. Spring, T. Wilson

7. Enhanced Efficiency Nitrogen Fertilizer: Coated Urea

Nitrogen is the most common fertilizer applied to crops, as it is typically the limiting nutrient in plants. However, about half of the nitrogen added to soil as fertilizer is either emitted to the atmosphere as ammonia, nitrous oxide or other gaseous forms, or finds its way into surface or ground waters as nitrate (Kibblewhite, 2007). The inefficient use of fertilizers depletes natural resources, and increases atmospheric emissions and environmental pollutants. With the use of enhanced efficiency... B. Geary, S.R. Fahning, B.G. Hopkins

8. Stacking and Intersecting Nutrient 4Rs and Using In-Season Canopy Health and Petiole Nitrate Analysis on Russet Burbank Potatoes

The 4Rs of nutrient management is a global outreach with an aim to improve the sustainability of major cropping systems and the environment. The objective for this project is to evaluate individual and stacked 4R management practices and how they intersect in Russet Burbank potato at a field near Grace, Idaho in 2020. Nitrogen (N) fertilizer treatments included all combinations of two sources [urea vs polymer coated urea (PCU)], two rates (207 vs. 247 kg ha-1), and two timing/placements... S. Stapley, B. Hopkins

9. Assessing Nutrient Uptake and Accumulation in Oregon Hop Production

Commercial hop production practices and cultivars have changed in the past 25 years and there is a need for updated nutrient management information under cotemporary practices. Current nutrient accumulation curves are only available for nitrogen (N). Current regional nutrient management guides from Oregon State University and Washington State University date back to the 1990’s or earlier. In the meantime, market forces and breeding efforts have led to a proliferation of new varieties, many... A. Moore, D. Gent, B. Verhoeven

10. Nitrogen and Water Management for Optimized Sugar Beet Yield and Sugar Content

Sugar beet (SB) production is based on maximizing: root yield, and sucrose content, and sucrose recovery efficiency. Efficient nitrogen (N) and water management are key for successful SB production. Nitrogen deficits in the soil can reduce root and sugar yield. Overapplication of N can reduce sucrose content and increase nitrate impurities which lowers sucrose recovery. Application of N in excess of SB crop need leads to vigorous canopy growth, while compromising root development and sugar production.... O.S. Walsh, S. Shafian, D. Jayawardena

11. Sensor-Based Nitrogen for Spring Wheat

Management of nitrogen (N) fertilizer during wheat production needs to vary depending on the variety as they have different N requirements. Though many growers prefer planting older varieties that they are already familiar with, increasing the knowledge on N requirements of newly released varieties will help to improve the adoption of these varieties by growers. Therefore, the main goals of this study were to assess grain yield, grain N uptake and N use efficiency (NUE) of new and traditional... D.M. Jaywardena, O.S. Walsh

12. Residue Decomposition of Surface and Incorporated Barley, Corn, and Wheat at Varying Fertilizer-N Rates

Cereal crops are commonly grown in southern Idaho and most parts of the western United States. These cereal crops are routinely harvested for their grain with the remaining plant material (chaff, stems, leaves, etc.) left in the field to decompose prior to planting of following spring crops. Understanding the effects of post-harvest residue management on barley (Hordeum vulgare L.), corn (Zea mays L.), and wheat (Tritcum aestivum L.) residue is important for optimizing... C. Rogers, G. Thurgood, B. Dari, J. Marshall, O.S. Walsh, K. Schroeder, G. Loomis

13. Is Residue Management an Important Factor in the Soil Health of Perennial Grass Seed Production Systems?

Residue management in agricultural systems is a crucial pathway of nutrient and organic matter flow and is predicted to affect soil health indices. In Western Oregon, perennial grasses for seed are a major crop, occupying roughly 150,000 ha in the Willamette Valley. Current estimates are that 80-85% of producers remove straw residue, exporting more than 650,000 US tons of straw annually. The primary objectives of this study were: i) evaluate soil health outcomes under residue retention and removal... B. Verhoeven, A. Moore, D. Sullivan, M. Gonzalez-mateu

14. Improving Nutrient Use Efficiency in Irrigated Areas of Western Agriculture

Much of Western US crop production requires irrigation for optimum performance. Irrigated cropping systems often include high-value crops grown with intensive nutrient management. Irrigation management is integral with nutrient management, especially for nitrogen. The predominant form of plant-available nitrogen in soils is nitrate, which is highly mobile and greatly affected by irrigation management. Irrigation, therefore, adds complexity to already intensive management and introduces challenges... A. Blaylock

15. Irrigated Cereal Response to Nitrogen Applications to Improve Efficiencies for Yield and Protein

High yielding and quality barley (hordeum vulgare L.) is critical for producing malt. Research trials investigating the impact of final irrigation timing cutoffs [i.e., late boot, soft dough, and soft dough + 7 days (SD7)] and nitrogen (N) rates (0 to 150 lb N/ac) at the Kimberly Research and Extension were conducted during the 2015 growing season. Our study measured yield and quality factors as well as N uptake and partitioning. Cutoff of irrigation at the boot stage severely stressed plants... C. Rogers, B. Dari, H. Neibling

16. Cover Crops As A Source Of Plant-Available Nitrogen: Effect Of Residual Soil N And Cover Crop Species

Fall-planted brassica and small grain cover crops have the potential to serve as catch crops by taking up residual soil nitrogen (N) in the soil. While plant species is often considered when estimating N release rates from cover crop residues, variation in residual soil N is rarely considered. The first objective of this study was to quantify the effect of N fertilizer application rate (to simulate varying residual soil N levels) on tissue N concentrations of several cover... J. Neuman, D. Sullivan, A. Moore

17. Nitrogen Management in Small Grains After Alfalfa

Small grains are commonly grown following alfalfa in Utah and the Intermountain West, especially during drought years as small grains require less irrigation than corn. Several studies across the country have shown that corn following alfalfa rarely needs N fertilizer, yet relatively few have evaluated the N needs of small grains. Furthermore, research on the N needs of small grains grown as forage vs. grain are even more sparse. The objectives of this research are to quantify the... C. Pound, M. Yost, E. Creech, G. Cardon, K. Russell, D. Despain, J. Gale, K. Heaton, B. Kitchen, M. Pace, S. Price, C. Reid, M. Palmer, M. Nelson

18. Polymer Coated Urea in Kentucky Bluegrass

Nitrogen (N) is a commonly over-applied nutrient in urban environments. This over-application has led to nutrient pollution of the atmosphere and hydrosphere. The losses of N to the environment can be mitigated with the use of enhanced efficiency fertilizers, such as polymer coated urea (PCU). Some PCU labels state that a single annual application is a best management practice. The objective of this study was to evaluate a PCU compared to monthly applications of ammonium sulfate/urea.... S. Stapley, J. Buss, B. Hopkins

19. Evaluation of Soil Tests for Potentially Mineralizable Soil Nitrogen in Snake River Plain Soils in Idaho

Soil testing is a critical component of fertilizer management strategies for ensuring optimal nutrient applications for agricultural crop production while minimizing potentially negative environmental impacts due to excess fertilizer applications. Research to determine accurate soil test methodologies dates back over 150 y; however, a rapid soil test for the determination of potentially mineralizable nitrogen (N) that consistently provides reliable results has alluded researchers. A recent resurgence... C. Rogers

20. Sustaining Agriculture and the Environment Through Healthy Soils

Soil health can be defined as the continued capacity of soil to function as a vital living ecosystems that sustains plants, animals, and humans. Land management practices that enhance soil health offer many opportunities to respond effectively to current challenges to agricultural sustainability and environmental quality. Practices such as cover crops and no-till can enrich mineral soils with organic carbon, enhance water infiltration, and increase the available water holding capacity... S. Shafer

21. Effects of a One-time Compost Addition on Soil Health in a Rainfed Dryland Organic Wheat System

Maintaining adequate soil fertility and health is a challenge in dryland organic wheat systems. This research examines the short-term impact of a one-time addition of compost on the soil health in a rainfed dryland organic winter-wheat (Triticum aestivum L.) fallow system. Field plot experiments were established in 2015 in a semiarid dryland organic wheat field in Snowville, Utah with the following treatments: control (C), compost at 12.5 Mg/ha dry weight (CM1), 25 Mg/ha (CM2), 50 Mg/ha... I. Atoloye, J. Reeve, A. Jacobson, E. Creech

22. Accumulation and Partitioning of Nutrients by Irrigated Sugar Beets During the Growing Season in Southern Idaho

Amounts and rates of dry matter and nutrients for irrigated sugar beets (Beta vulgaris L.) during growing season have received limited attention. A study was conducted during the 2014, to evaluate amounts, rates, and partitioning dynamics of dry matter, macro- (N, P, K, Ca, Mg, S, and NA), and micro- (Fe, Mn, Zn, Cu, and B) nutrients accumulated by sugar beet in different growth stages under minimum-stress field environment on an irrigated Portneug silt loam soils of southern idaho. Urea, mono-ammonium... M. De, A. Moore, R. Mikkelsen

23. Effect of Cover Crops and Compost on Soil Water Availability in Organic Dryland Wheat

In low input semi-arid regions, water is the major limiting factor in crop production. Cover crop biomass and compost are good source of organic matter, that improve biological activity and water holding capacity of soils. However, dryland organic wheat growers rarely apply soil amendments due to cost and cover crops can lead to the depletion of soil water which decreases the yield of subsequent winter wheat. This study investigates the potential for a synergy between compost addition and cover... K. Adeleke, J. Reeve, E. Creech, I. Atoloye

24. Nitrogen Management and Water Productivity of Grain Crops Under Drought or Limited Irrigation

The interactions of nitrogen management and water have been the subject of many studies that have improved crop management practices. Water scarcity however, has become a pressing contemporary challenge for agricultural and food sustainability, especially in many arid and semi-arid regions of the world. As the amount of available water for irrigation decreases, more studies must shift their focus to how nitrogen fertilizers influences water use efficiency. Numerous strategies are currently employed... S. Evans, N. Hansen, A. Blaylock

25. Phosphorus and Organic Acid Bonding Impacts at Varying Soil pH

Phosphorus (P) fertilizer is essential for crop production, but reductions are warranted to conserve resources and minimize environmental impacts. Several lab, glasshouse, growth chamber, and field studies have been performed over the past six years with a new P fertilizer (Carbond P; CBP; Land View Fertilizer, Rupert, ID, USA) mostly in calcareous, low OM soil. Studies comparing CBP to ammonium polyphosphate (APP) and monoammonium phosphate (MAP) applied to soil show season-long increases in... T. Blair, C. Ransom, P. Hosford, J. Svedin, L. Sutton, A. Winchester, K. Manning, T. Hopkins, B. Hopkins

26. Understanding Crop Response to Micronutrients

There are many factors that affect crop response to micronutrients, and response to micronutrients is often less predictable than response to N, P, and K. Responses to micronutrients may be dramatic if the nutrient is deficient, but more often, responses are incremental yield increases or even only maturity or quality improvements. Micronutrient chemistry in the soil is complex and there are numerous interactions with other nutrients and environmental conditions. While predictability of micronutrient... A. Blaylock

27. Pecan Response to Foliar Nickel Applications

New Mexico’s pecan industry is one of the state’s most important agricultural assets. In 2010, pecan growers in Dona Ana County produced 19,504 kg of pecans, on over 10,000 ha and was worth over $123 million dollars, making Dona Ana county the number one pecan producing county in the nation. Nickel (Ni) is a component of the enzyme urease which is critical for the mobilization of nitrogen within the pecan tree. Deficiency symptoms are often expressed in pecan as a “mouse-ear”... R. Flynn, R. Heerema, S. Moran duran

28. Nitrogen Balances in Dairy Production Systems in Southern Idaho

Nitrogen (N) is essential for agricultural production, but excess quantities can be detrimental to both water and air quality. The increase in dairy cattle populations in the Magic Valley of southern Idaho has lead to concerns over the impact of N losses to the environment and the impact on both water and air in the region. This work examines the N flows and balances at the production facility, whole farm and regional scale. At the production facility, approximately 60% of N imported was lost... A. Leytem

29. Chloride Effects on Nitrogen Uptake in Potato Production

Potassium (K) can be supplied by potassium chloride (KCl) or sulfate (K2SO4) salts. Past research has shown that potatoes can take up and accumulate large amounts of chloride (Cl). Plant uptake of Cl can sometimes reduce petiole nitrate-N (NO3-N) concentration and it may have other effects on potato tuber yield and quality. In contrast, sulfate-S (SO4-S) typically does not compete strongly with NO3-N for plant uptake. This research was designed to evaluate the effect of Cl application on petiole... D. Sullivan, S. Light, D. Horneck

30. Utilizing Low Salt Liquid NPK Fertilizers to Establish Triticale As a Cover Crop

The use of cover crops in sustainable agricultural systems is receiving renewed attention. New initiatives in soil health promote cover crops as amanagement tool to improve soil quality and health. Successful establishment of cover crops depends on an adequate soil fertility program. Low salt NPK liquid fertilizers can improve cover crop establishment without concern of the impact of high salt index of some conventional fertilizers. This paper presents some of the success that have been observed... G. Mooso, T. Tindall

31. Turf Response to Reduced Rates of Polymer-coated Urea

Polymer-coated urea (PCU) is a controlled-release fertilizer which can enhance nitrogen (N) use efficiency (NUE), reduce N pollution, reduce the need for repeated fertilizer applications, and reduce turfgrass shoot growth and associated costs. A PCU fertilizer rated for 120 d was applied at 50, 75, and 100% of the recommended full rate and compared to an unfertilized control and urea, applied either all at once or split monthly at the full recommended rate. Spring applied PCU showed no initial... B. Hopkins, C. Ransom, M. Ruth, T. Blair, L. Sutton, D. Bradshaw, K. Campbell

32. Phosphorus and Organic Acid Bonding Enhances Uptake Efficiency and Yield Response in Crop Plants

Phosphorus (P) fertilizer is essential for crop production, but reductions are warranted to conserve resources and minimize environmental impacts. Several lab, glasshouse, growth chamber, and field studies have been performed over the past seven years with a new P fertilizer (Carbond P; CBP; Land View Fertilizer, Rupert, ID, USA) in calcareous, low OM soil. This paper will be a review of a portion of that data. Studies comparing CBP to ammonium polyphosphate (APP) and monoammonium phosphate (MAP)... B. Hopkins, T. Blair, J. Selman, C. Ransom, T. Hopkins

33. Evaluation of Nitrogen Gas Loss from Polymer Coated and Polymer Sulfur Coated Urea

Previous research showed reduced nitrogen (N) gas emissions from polymer coated (PCU) and polymer sulfur coated urea (PSCU) when surface applied to soil. To further verify and quantify (N) loss, experiments were conducted to measure N gas emissions. Fertilizer prills were surface applied in a semi enclosed system to allow atmospheric gases in but to prevent loss of N gases from the headspace. Nitrous oxide (N2O) and ammonia (NH3) emissions were continuously measured every 20 minutes using photoacoustic... B. Hopkins, J. Svedin, C. Ransom, J. Buss, T. Blair

34. Phosphorus and Organic Acid Bonding Enhances Uptake Efficiency in Crop Plants

Phosphorus (P) fertilizer is essential for crop production, but reductions are warranted to conserve resources and minimize environmental impacts. Several lab, glasshouse, growth chamber, and field studies have been performed over the past five years with a new P fertilizer (Carbond P; CBP; Land View Fertilizer, Rupert, ID, USA) in calcareous, low OM soil. This presentation will be a review of that data. Studies comparing CBP to ammonium polyphosphate (APP) applied to soil show season-long increases... B. Hopkins, T. Blair, M. Hill, C. Ransom

35. Nitrogen Transformations in Flooded Agroecosystems: a Case Study with Taro (Colocassia Esculenta)

Wetland agriculture covers an estimated 170 million ha and contributes significantly to global food supply. Nitrogen fertilizers are subject to numerous potential transformation pathways in flooded systems. The present research was focused on improving our understanding of N transformations in a flooded agricultural system by addressing the following two broad objectives: 1) determine whether the presence of anammox bacteria and its activity contribute significantly to N losses, and 2) evaluate... J. Deenik, C. Penton, B. Popp, G. Bruland, P. Engstrom, J. Mueller, J. Tiedje

36. Exploring Controlled Release Nitrogen Fertilizers for Vegetable and Melon Crop Production in California and Arizona

Various forms of polymer coated urea (PCU) were examined as sources of controlled release nitrogen for production of cauliflower, watermelon, carrot, and spinach in Arizona or California. Studies were designed to demonstrate the effectiveness of PCU for supplying 100 percent of the fertilizer nitrogen needed for an entire growing season in a single pre-plant application. In each study, two or more N rates were tested. PCU having an appropriate release time for a given set of growing conditions... R. Smith, A. Blaylock, E. Ellison, C. Sanchez

37. Nitrogen Dynamics in Conventional, Reduced Tillage and Organic Irrigated Systems: Results of a Four-year Experiment in Wyoming

Soil nitrogen (N) is critically important for crop production. A field experiment was conducted in eastern Wyoming to evaluate soil mineralizable (mineralized in 14 days incubation) and inorganic N contents as influenced by conventional, organic and reduced-tillage management approaches for cash-crop and forage production in eastern Wyoming. Soil samples were collected from all treatments (2 production systems x 3 management approaches) during 2009-2012 and analyzed for soil mineralizable and... R. Ghimire, J. Norton

38. Integrating Fertilizer and Manure Nitrogen Sources in Irrigated Agriculture

Sharp increases in fertilizer prices are pushing growers to consider alternative nutrient sources for their crops. For growers in the western U.S. who produce crops in regions that also contain intensive animal production, manure can be a very affordable alternative nutrient source to chemical fertilizers. However, manure does not have the appropriate balance of nitrogen (N), phosphorus (P), potassium (K), and other nutrients to meet the nutrient needs of most crops. The goal of this article is... A. Moore

39. Soil Copper Thresholds for Potato Production

A rising concern with the application of dairy wastes to agricultural fields is the accumulation of copper (Cu) in the soil. Copper sulfate (CuSO4) from cattle footbaths is washed out of dairy barns and into wastewater lagoons. The addition of CuSO4 baths on dairies can increase Cu concentration significantly in manure slurry. The Cu-enriched dairy waste is then applied to agricultural crops, thus raising concerns about how soils and plants are impacted by these Cu additions. Repeated applications... A. Moore, M. Satterwhite, J. Ippolito

40. Phosphorus Use Efficiency in Crop Production

The limited availability of phosphorus (P) in calcareous and acidic soils can be a major factor that limits crop production. The objectives of this study were to investigate the mobility and availability of P from monoammonium phosphate (MAP), diammonium phosphate (DAP) and ammonium polyphosphate (APP) fertilizers alone and with AVAIL, a fertilizer enhancement product. Two different soil types were used to examine the relationship between P reaction products and available P. Soils were incubated... G. Mooso, T. Tindall, G. Hettiarachchi

41. Polymer Coated Urea (ESN): Impacts on Potato Crop and N Losses

Potato (Solanum tuberosum L.) production is sensitive to a steady, adequate supply of nitrogen (N). Synergistically optimizing grower profits while maximizing N use efficiency (NUE) is critical to conserve nonrenewable natural resources used to manufacture N fertilizer and minimize N pollution to water and the atmosphere. Polymer coated urea (PCU, Environmentally Smart N or ESN®) is one type of N fertilizer which uses temperature-controlled diffusion to control N release to better match plant... B. Hopkins, C. Ransom, T. Taysom, J. Lemonte

42. Polymer Coated Urea (Duration) in Turfgrass: Impacts on Mowing, Visual, and Loss to Environment

Fall and spring applied N fertilizer trials were conducted over two years in an effort to determine if various slow and controlled release N fertilizers were equivalent to traditional urea and to determine if a reduced rate of controlled release N could be used for improved N use efficiency. An unfertilized control was compared to sulfur coated urea (SCU), polymer and sulfur coated urea (XCU), polymer coated urea (Duration 75 or 125; DR) at 50, 75, and 100% (full) rate, and urea either applied... B. Hopkins, L. Sutton, C. Ransom, T. Blair, J. Moody, K. Manning, S. Bergsten

43. Development and Use of the OSU Organic Fertilizer and Cover Crop Calculator

Farm advisory visits in Oregon highlighted the need for decision tools to help farmers and agricultural professionals estimate nitrogen (N) mineralization from organic fertilizers and cover crops, design balanced fertilizer plans and identify the most cost effective nutrient management options. Laboratory and field research was conducted to develop N mineralization models for organic fertilizers and compost based on the total percent N. Field methods for estimating cover crop biomass and total... N. Andrews, D. Sullivan, J. Julian, K. Pool

44. Improving Phosphorus Use Efficiency with Carbond P

Phosphorus (P) fertilizer is integral for maximizing crop production and is used abundantly to achieve desired yields. However, reduction of P fertilizer is warranted, as it is the primary source of nutrient pollution in surface waters (eutrophication leading to hypoxia) and is derived from non-renewable mineral resources. Two research studies were conducted in 2009 to evaluate a new fertilizer product, Carbond® P against traditional fertilizers ammonium polyphosphate (APP) and monoammonium... B. Hopkins, B. Webb, M. Hill, C. Ransom

45. Managing Alfalfa Under Low Water or Drought Conditions

... L. Lauriault

46. The Dos and Don’ts of High Residue Farming in the Irrigated Far West

... A. Mcguire

47. Influence of Dairy Manure Applications on Corn Nutrient Uptake

Corn silage is the predominant crop in Idaho used for recovering phosphorus (P) that has accumulated in soils from dairy manure applications. However, little is known about how much phosphorus and other nutrients are being recovered under Idaho conditions. The objective of the study is to estimate phosphorus removal by irrigated corn silage crops cultivated throughout Southern Idaho with variable soil test P concentrations, and to identify effects of increasing soil test P on potassium (K), calcium... A. Moore, B. Brown, J. Ippolito, S. Hines, M. De haro marti, C. Falen, M. Chahine, T. Fife, R. Norell

48. Nitrogen and Phosphorus: Mechanisms of Loss from the Soil System and Effects to Slow Those Losses and Increase Plant Availability

Nutrient management issues associated with production agriculture are becoming more of a concern and a focal point of discussion. Management considerations are no longer focused on just meeting yield goals or improved crop performance, but now include questions on how their use on agriculture lands impacts surface water, watersheds, soil quality, long-term health benefits and economic viability for the producer. ... T. Tindall, G. Mooso

49. K Fixation and Significance for Crop Production

Some cultivated soils in California found on the east side of the San Joaquin Valley (SJV) and derived from granitic parent material have the capacity to fix added K, making it unavailable or less available to crops. The main soil mineral responsible for K fixation is vermiculite, which is a weathering product of mica, and which can occur in the clay, silt, and fine-sand size fractions. We have developed a model that predicts the location of K-fixing soils in the region and a practical soil test... S. Pettygrove, T. O'geen, R. Southard

50. Dicarboxylic Acid Polymer (Avail®) Phosphorus Fertilizer Additive: Review

Improving P use efficiency (PUE) is desirable but difficult due to poor P solubility in soils. A dicarboxylic acid copolymer (AVAIL®) fertilizer additive may enhance PUE due to increased P solubility as a result of sequestering of interfering cations. Field trials have been conducted on a wide variety of crops, with results to AVAIL addition to P fertilizer mixed—seemingly related primarily to soil test P concentrations and fertilizer P rate. Positive results were seen in many of these... B. Hopkins, C. Ransom

51. Sheep Grazing Effect on Dryland Soil Carbon and Nitrogen in the Wheat-fallow System

Weed control by sheep grazing during fallow periods in the dryland wheat-fallow system may influence soil C and N levels. The effects of fallow management for weed control and soil water conservation [sheep grazing (grazing), herbicide application (chemical), and tillage (mechanical)] and cropping sequence [continuous spring wheat (CSW), spring wheat-fallow (SW-F), and winter wheat- fallow (WW-F)] on wheat biomass (stems + leaves) yield and soil organic C (SOC) and total N (STN) at the 0-120 cm... A. Lenssen, U. Sainju, H. Goosey, E. Snyder, P. Hatfield

52. Phosphorus Dynamics in Organic Matter-amended Soils

Generally, phosphorus (P) is considered immobile in calcareous soils. Yet, numerous studies have found that the addition of organic wastes (e.g. manures) can enhance P mobility in these soils. We believe that the soluble organic matter present in these wastes increases P solubility by inhibiting the sorption of inorganic P on soil colloidal surfaces and subsequently preventing the formation of insoluble calcium phosphates. This results in increased P bioavailability. Likewise, tests used to assess... P. Grossl, R. Koenig, C. Jones, S. Trolove

53. Biofuel Byproducts As Nitrogen Sources for Crops

The new development of ethanol and biodiesel plants in the United States is creating a large, and potentially excessive, quantity of byproducts in the forms of distillers grains and oilseed meals. The organic nitrogen (N) compounds in these byproducts rapidly mineralize in soils, showing the potential to be used as a N fertilizer source to plants. The objective of this research is to evaluate the application of biofuel byproducts on yield, size distribution, and nutrient uptake for Russet Umatilla... A. Moore, A. Alva, H. Collins, R. Boydston

54. Urea and Ammonia Volatilization in Dryland Grass Seed Systems1

The purpose of this study was to evaluate the influence of grass seed production conditions and management practices on NH3 volatilization, Kentucky bluegrass seed yields and N recovery from urea. Laboratory incubations suggest the potential for NH3 volatilization is greater from stands in which post-harvest residue is baled and removed than from stands in which residue is burned. Both burned and unburned stands have a surface pH > 7.9, although pH declined with time in the burned... R. Koenig, C. Proctor, W. Johnston, C. Golob

55. Phosphorus Dynamics and Wheat Response to Applied P in a Spatially Variable Environment1

Considerable spatial and temporal variability exists in soil chemical and physical properties across farm landscapes in eastern Washington State. The purpose of this research is to investigate changes in P mineralogy across the Palouse landscape and ultimately to determine the influence of mineralogy on plant-available P and fertilizer P responses at different landscape positions. Soil samples were collected from landscape positions with varying soil pH and soil test P concentrations. Mineral... R. Koenig

56. Reducing Dairy Effluent Phosphorus Content Through Struvite Production

Forced precipitation of struvite (magnesium ammonium phosphate hexahydrate, MgNH4PO46H2O) in wastewater treatment has recently received increased attention as a method of phosphorus (P) recycling. Dairy lagoon P concentrations can be lowered, and the recovered struvite has the potential to be marketed and used as a fertilizer. Struvite may even be useful in organic production on calcareous soils, where rock P (PR) is not an option. A new organic treatment method, based on an existing... J. G. davis, J. Ippolito, M. Massey, R. Sheffield

57. Managing Potassium for Organic Crop Production

An adequate potassium (K) supply is essential for both organic and conventional crop production. Various organic certification agencies have different regulations governing allowable sources of K. The release of K from soil minerals is discussed along with the behavior of various allowed K sources for organic crop production. ... R. Mikkelsen

58. Removing Nitrogen, Phosphate, and Fecal Coliform from Dairy Effluent Using Multi-soil-layer (Msl) Systems

Dairy effluent disposal has long been a concern in Hawaii. Dairies often establish multiple lagoons to accumulate and store effluent. Occasionally, the lagoons overflow leading to the transfer of nutrients, such as nitrogen (N) and phosphorus (P), and other contaminants such as pathogenic bacteria to surface, subsurface, and coastal waters. The objective of this study was to quantify the effectiveness of MSL systems in removing inorganic nitrogen, phosphate, and fecal indicator organisms (Fecal... R. Yost, R. Pattnaik, G. Porter

59. Manure Treatments Change Nitrogen Cycling in Soils Receiving Repeated Applications of Dairy-wastes

Our objective was to assess effects of treated dairy-waste on soil N pools, nitrification, plant N availability, and yield in a silage cornfield treated with ammonium sulfate (AS), dairy-waste compost (DC) or liquid dairy-waste (LW) as N sources at two levels of application over 5 years. Increases in soil C and N, nitrate and available P and K were observed for the DC treated soils throughout the 5-year period. Soil organic C increases for the high-level DC treated soil doubled the C pool resulting... J. Norton, M. Habteselassie, J. Stark, B. Miller

60. Grain Protein Content and Composition of Winter Wheat Cultivars Under Different Levels of N and Water Stress

This study investigated the combined influences and interactions of N fertilization and moisture deficit during grain-fill on wheat grain protein content and grain protein composition of nine white winter wheat cultivars. Grain was obtained from seven HWW wheat cultivars and two soft white winter (SWW) wheat cultivars grown under line-source irrigation systems at two Oregon locations during two years. The low N level treatment consisted in a single fertilization of 150 lb N/a in March,... A. Ross, C. Saint pierre, C. Peterson, J. Ohm, M. Verhoeven, M. Larson, B. Hoefer

61. Predicting Phosphorus Runoff from Calcareous Soils

Studies have shown that as extractable soil P levels increase, runoff P levels also increase. This relationship has been found on many different soils, but tends to be unique for each soil series. Very little research exists evaluating this relationship in calcareous soils. The objectives of this study were to determine soil series specific relationships between soil test phosphorus (STP) and runoff P for three calcareous soils, to compare the use of different soil extractants for runoff P prediction... J. G. davis, R. Schierer, J. Zumbrunnen

62. Remote Sensing of Grape K Deficiency Symptoms Using Leaf Level Hyperspectral Reflectance

Potassium (K) is an important nutrient for grape because it sustains charge neutrality during organic acid transport, is a major ion involved in osmoregulation and stomatal function and contributes to pH status in grapes and wines. We assessed the utility of a number of vegetation indexes for detection of K deficiency symptoms in a commercial vineyard of Vitis vinifera cv Pinot Noir. A hyperspectral field spectroradiometer for the 350-2500 nm spectral region was used to measure light reflectance... D. Smart, M. Whiting, C. Stockert

63. Evaluation of N Uptake Analysis As a Tool for Determing Potato N Status

Plant tissue testing has become the primary method for evaluating nitrogen availability for potatoes during the growing season. This study was conducted to determine if plant N uptake rates referenced to absorbed solar radiation could also be used as a tool to quantitatively assess plant N status of different potato varieties. Nitrogen fertilizer, as NH4NO3 (34-0-0), was applied to Russet Burbank, Gem Russet, Bannock Russet and Summit Russet at three rates (0, 100, or 300 kg N/ha) using two... J. Stark, S. Love, C. Mcintosh

64. Recent Advances in P Fertilizer Technologies—polymer Coatings and Avail Technology

Phosphorus fertilizers are an essential part of plant production and have been recognized as such for well over 100 years. Phosphorus utilization by crops is related to both soil availability as well as an individual plants metabolic process that allows P to be taken up by a plant as well as utilized for a wide variety of developmental processes. ... T. Tindall

65. Nutrient Cycling in Effluent-irrigated Soil (Mollisol) Planted to Tropical Grasses in a Tropical Island Environment

Dairy producers accumulate large quantities of effluent in lagoons. Lagoons occasionally overflow causing the nutrients and other contaminants in effluent to pollute the land and water bodies. Alternative uses of effluent are, therefore, urgently needed for a sustainable and environment-friendly dairy production. This study determined the sustainable effluent application rate and assessed the effects of effluent irrigation on plant and soil (Cumulic Haplustoll) properties. Five tropical grasses—... R. Valencia-gica, R. Yost, G. Porter, R. Pattnaik

66. Soil Zinc Application for Southwestern Pecan

Pecan trees grown in the alkaline soils of the southwestern United States are prone to zinc deficiency unless supplemental zinc is regularly applied. Standard treatment involves multiple foliar zinc applications. Soil zinc application would provide several advantages. A field study was initiated in 2005 with three soil zinc treatments: no zinc (control), ZnSO4 (74 kg.ha-1 Zn), or ZnEDTA (19 kg.ha-1 Zn) were applied one time in March, 2005 in bands 18 cm deep and 1.2 m on both sides... J. Walworth, A. Pond, H. Nunez, B. Wood, M. Kilby

67. Improved Small Grain Nitrogen Use Efficiency with California Site-specific Decision Support

Small grains are grown throughout the state of California (CA) on approximately 500,000 acres annually. They are generally fall-sown and grown during the winter months when most precipitation occurs. Because precipitation and irrigation patterns vary across CA and there is a strong interaction between total water and plant available nitrogen (N), determining fertilizer N application recommendations is particularly challenging in this cropping system. With recent fertilizer price volatility,... N. Clark, M. Lundy, T. Nelsen, M. Leinfelder-miles, S. Light, G. Galdi, T. Getts, K. Mathesius

68. Performance of Public and Private Fertilizer Recommendations for Corn, Alfalfa, and Small Grains

There are many sources that growers utilize to determine fertilizer needs for crops such as private and public labs, crop advisors, and fertilizer dealers. In many cases, these sources provide recommendations for a specific crop that can vary greatly, and the resulting fertilizer and application rates recommended can lead to large differences in costs for the grower. Evaluating the effectiveness and economics of current fertilizer guidelines and recommendations will help growers to make better-informed... M. Yost, M. Baker, J. Gale, E. Creech, G. Cardon

69. Evaluating Zinc Requirements of Corn, Small Grains, and Alfalfa

Many growers and crop advisors in the Intermountain west have recently reported Zn deficiencies in major cereal and forage crops. Further, many common fertilizer blends now include Zn. Most Zn fertilizer guidelines indicate that 5-10 lbs of Zn per acre should be applied when critical soil test Zn levels are less than about 0.8 ppm Zn. These guidelines in Utah and many other states in the region were developed decades ago and need to be reassessed. Therefore, we established Zn response and rate... M. Yost, M. Baker, J. Gale, G. Cardon, E. Creech

70. Sus-Terra Enhanced Efficiency Phosphorus Fertilizer on Potato Grown in Calcareous Soil

Potato (Solanum tuberosum L.) has a relatively high demand for phosphorus (P), especially on calcareous soil where the availability of P in hindered by poor solubility. Sus-Terra is claimed to be an enhanced efficiency fertilizer compared to other P sources. The objective of this trial was to evaluate the differences in uptake efficiency and yield for multiple P sources compared to a no P control applied to Russet Burbank potato. Field trials with six replications in a RCBD were... L.K. Sannar, B.G. Hopkins, T.J. Hopkins

71. The Effects of Calcium Source and Placement on Soil Factors and Wheat Performace Factors

Wheat production is a critical component of U.S. Pacific Northwest agriculture, with approximately 80% of the global soft white wheat grain supply originating from this region. Ammonium-based nitrogen fertilizers are widely used on typically alkaline soils in Eastern Oregon dryland production areas by wheat growers. However the nitrification process that biologically converts ammonium to nitrate increases the soil concentration of H+. This process ultimately creates acidic soil conditions, which... S. Ellickson, A. Moore, R. Zemetra, C. Hagerty

72. Alfalfa Fertility Survey of Oregon, Washington, and Idaho

Understanding alfalfa nutrient status in plants and soils allows researchers and growers identify the greatest nutrient needs for this important crop. A survey of PNW alfalfa fields is being conducted to accurately summarize alfalfa nutrient uptake and biomass yield potential in response to soil agronomic properties to address this question. Forty alfalfa fields throughout alfalfa production regions in Oregon, Washington, and Idaho were selected for the 2022 survey. The number of fields collected... C.H. Messman, A. Moore

73. Nutrient Management for Semi-arid Cannabis Production

The industrial hemp (Cannabis sativa L.) industry rapidly emerged in Utah in 2019 with nearly 480 new hectares of hemp production. Production declined and stabilized during 2019-2022 due to low returns in a flooded pharmaceutical market. Though small and specialized, the hemp production industry is still viable in Utah and surrounding states. Many questions remain on optimal production practices for this new and potentially high-value crop. Research throughout the United States... T. Sullivan, M. Yost, D. Boren, E. Creech, B. Bugbee

74. The Ammonia Rainbow

Agriculture has been identified as a major contributor to atmospheric carbon dioxide with nitrogen fertilizer production as a key component. Recent scrutiny of nitrogen production processes has identified ammonia production processes to reduce carbon output from traditional Haber-Bosch processes.  These different ammonia production processes are often described with color descriptions to designate the processes used and qualitatively identify their carbon footprint, such as “green ammonia”,... A. Blaylock

75. Evaluation of Soil Sulfur Tests for Montana

There are no sulfur (S) fertilizer rate guidelines in Montana due to inconsistent yield responses, high S soil levels in many regions, a minimal number of S fertility trials in the state, and the lack of Montana and regional data that identify the best soil S tests to use. A study was initiated in 2023 to fill this research void. Three crops (spring canola, pea, and wheat) were grown at three sites, and fertilized with 0, 7.5, 15, and 30 lb S/ac using two S sources (potassium sulfate, gypsum)... C. Jones, P. Miller, P. Carr, S. Koeshall, S. Fordyce, J. Souza, J. Vetch

76. Dairy Manure Applications to Potatoes: Soil Property, Plant Nutrient, and Tuber Quality Response

Dairy manure applications have become a common practice in Idaho potato production, however the impacts on soil and plant agronomic properties are not well understood. Our objectives were to determine (1) how repeated dairy manure applications impact soil properties and plant nutrient uptake, and (2) how these changes influence plant nutrient interactions, tuber yield, and quality. Stockpiled dairy manure was fall-applied over a 6-year period to two adjacent potato production... A. Moore, A.B. Leytem

77. Application Timing, Soil Type, and Source Effects on Elemental S Availability

The reduction in acid rain due to increased regulation of manufacturers in the U.S. has led to S deficiencies in agricultural crops. In response, elemental sulfur (S) fertilizer products are becoming more widely available to growers, but have not been evaluated for their S availability and S oxidation characteristics. The objective of our research was to evaluate the S availability and S oxidation rates of five elemental S fertilizer products. The evaluation was done using two Oregon soil types... A. Cox, A. Moore

78. Soil Property Effect on Nitrogen Mineralization of Dairy Manure in the Pacific Northwest

Growers often use total nitrogen (N) concentration of dairy to manure to estimate plant available N for crop production. This estimate, however, ignores the role that soil properties may have on N mineralization (Nmin) rates. This study aims to determine how soil physiochemical properties impact Nmin rates of dairy manure and composted dairy manure by aerobic incubation. Sixteen soils, sampled from 0-12 inch depths (0-30.5 cm) were collected from dairy production regions in Oregon, Washington,... R. Auld, A. Moore, J. Moore, Y. Zhang, C. Rogers

79. Greenhouse Lime and Gypsum Placement Strategies for Addressing Soil Acidity in No-till

Dryland soft white winter wheat growers in the inner Pacific Northwest states including Washington, Oregon, and Idaho practice no-till to preserve the health and structure of their soil. Beginning in the 1960's, due to the usage and ammonium fertilizers and the nitrification of these fertilizers, the natively alkaline soils in this region have become increasingly acidic resulting is issues like low soil pH, mineral nutrient deficiencies, and aluminum toxicity. Generally,... A. Moore, S. Ellickson

80. Converting Between Mehlich-3P and Olsen-P Soil Tests: What Can Go Wrong?

Varying methodologies for extracting plant-available phosphorus (P) have been proposed since the initiation of soil test development in the early 1900s. Two tests that were developed and are still used widely in both the United States and Europe are the Olsen and Mehlich-3 test. Olsen P is predominately used in high-pH soils and Mehlich-3 is  more common in neutral to acidic soils due to the nature of the extracting solutions. Many Western US soils are high pH and, thus, have used Olsen P... C. Rogers, Z. Simpson, J. Mott, P. Kleinman

81. Quinoa Mineral Nutrient Deficiency Symptoms and Concentrations

Major crop nutrient symptoms are well documented. In contrast, there is often minimal or no similar information for minor crops, including quinoa (Chenopodium quinoa Willd.). This knowledge gap can be efficiently filled by using hydroponic systems. However, creating multiple nutrient deficiencies with plants in the same study is challenging because nutrients are often added as dual nutrient salts. For example, if potassium sulfate is the potassium (K) source, varying K concentrations... B. Hopkins, G. Bell, S.V. Nelson, R.E. Sannar

82. Recovered Carbon Black from Pyrolyzed Tires as a Zinc Fertilizer for Field Corn in Calcareous Soils

Waste tires exist in immense quantities, representing a substantial pollution source containing a variety of environmentally concerning components, including the heavy metal zinc (Zn) added as Zn oxide (ZnO) during tire manufacture. Pyrolysis under high vacuum is a potential disposal solution. One of the by-products of this process is recovered Carbon Black (CB) that is enriched in Zn, an essential plant nutrient. Our objective was to determine if recovered CB from can serve as a fertilizer Zn... R.E. Sannar, E. Bremer, K. Greer, B. Hopkins