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2021 Western Nutrient Management Conference
2013 Western Nutrient Management Conference
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Authors
Ahola, J
Anderson, A.J
Arthur, D.K
Backman, K
Banuelos, G
Bauder, T
Bergsten, S
Bjorneberg, D
Bjorneberg, D.L
Blair, T
Blaylock, A
Bremer, E
Britt, D.W
Bronson, K
Bronson, K.F
Brown, P.H
Bruland, G
Brummer, J
Bryla, D
Buck, R.L
Bush, T.V
Cahn, M
Carpenter-Boggs, L
Carter, P
Cartwright, A
Chen, C
Cole, D.L
Collins, D
Crowe, V
D'Agati, K
Dari, B
Davenport, J
Davenport, J.R
Davis, A.G
DeVetter, L.W
Deakin, J.W
Deenik, J
Donaldson, A
Dungan, R
Ellison, E
Engstrom, P
Evans, C
Fahning, S.R
Fernandez, F.G
Fransen, S
Geary, B.T
Gent, D
Ghimire, R
Girma, K
Gonzalez-Mateu, M
Greer, K
Griffin, D
Griffin-LaHue, D
Haas, S
Harrison, J
Hartz, T
Heidenreich, D.T
Helseth, C
Heser, J
Hettiarachchi, G
Hill, M
Hoheisel, G.A
Hopkins, B
Hopkins, B.G
Hortin, J
Horwath, W
Housman, M
Howneck, D
Huggins, D
Huggins, D.R
Hunsaker, D
Ippolito, J
Jacobson, A.R
Jayawardena, D.M
Jeliazkova, E
Jensen, T
Jones, C
Kephart, K
Khalsa, S.S
Khan, Q
Kleinman, P.J
Kobza, S.J
Lambert, A.M
LeMonte, J
Lehrsch, G
Lentz, R
Llewellyn, D
Long, R
Loomis, G
Lyons, S.E
Machado, S
Manning, K
Marshall, J
McCauley, A
McCoy, M
McGrath, J.M
McIlquham, M
McLean, J.E
McVay, K
Mcilquham, M
Meyer, R
Michel, L
Miller, P
Miller, R
Mohammed, Y
Mon, J
Moody, J
Moore, A
Moore, E
Mooso, G
Mueller, J
Muhammad, S
Murrell, T
Nichol, C
Noel, B
Norberg, S
Norton, J
Norton, U
Olsen, D
Osmond, D.L
Peachey, R.E
Pearce, A.W
Penton, C
Petrie, S
Pettygrove, S
Popp, B
Potter, M
Ransom, C
Reganold, J
Reganold, J.P
Rhoades, R
Rick, T
Rieser, C
Rodgers, H
Rogers, C
Saa, S
Salehin, S
Sanchez, C
Sanden, B
Sarpong, K
Sarpong, K.A
Satterwhite, M
Schroeder, K
Seely, C.J
Shafian, S
Shawver, C
Shiwakoti, S
Slaton, N.A
Smith, R
Spackman, J.A
Spargo, J.T
Sparks, D
Spring, J
Stacey, N
Stapley, S
Stapley, S.H
Steenwerth, K
Stout, J
Sullivan, D
Sutton, L
Tallman, S
Tarkalson, D
Tarkalson, D.D
Taysom, T
Thurgood, G
Tiedje, J
Tindall, T
Van Vleet, S
Vargas, O
Verhoeven, B
Walsh, O.S
Walworth, J
Wang, G
Waskom, R
Weisshaar, E.M
Westermann, D
Whitefield, L
Wiebe, J
Wieme, R
Wilson, T
Yi, Q
Zabinski, C
Zapata, D
Zhu-Barker, X
van Diepen, L
Topics
Soil Fertility and Soil Health Testing
Manure and Compost Management
Recycled and Repurposed Nutrient Sources
Liming and Soil Acidity
Fertilizer Evaluations
Crop Nutrient Management
Nutrient Management of Agronomic Crops
Nutrient Management of Horticultural Crops
Organic Amendments, Cover Crops, and Soil Health
Type
Oral
Poster
Year
2021
2013
Home » Conference » Results

Conference

Filter results78 paper(s) found.

1. 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 thr... E. Jeliazkova, A. Moore, J. Spring, T. Wilson

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 cons... F. Fernandez, J. Spackman

3. Advancing Nitrogen and Irrigation Management for Row Crops and Biofuel Crops in the Western US

Nitrogen, irrigation and N by irrigation studies from West Texas and central Arizona are discussed. In the first study with surface drip, deficit irrigation, N fertilizer rate response was observed with cotton (Gossypium hirsutum L.) in 50 and 75 % ET replacement, but not with dryland or 25 % ET. Irrigation level response was evident with LEPA in two of three years in Lamesa Texas, but not in a wet, third year. Variable-rate N showed a more consistent response than blanket-rate N in that... K. Bronson, J. Mon, D. Hunsaker, G. Wang

4. 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, m... A. Moore, D. Gent, B. Verhoeven

5. Climate Change and Nutrient Management

Climate change models for the intermountain region of eastern Oregon and Washington project warmer and wetter winters with warmer and drier summers. Crop response to the projected climate change conditions were estimated using CropSyst. The anticipated climate changes and increasing CO2 levels are projected to result in greater yields of winter wheat with relatively small changes in yields of spring wheat, potatoes and apples. Greater yields will require increased nutrient supply and inc... S. Petrie

6. Comparative Analysis of Soil Tests for Soil Health and Nutrient Management

Options for soil tests to address soil health and nutrient management objectives have diversified. We compare different soil test methods to evaluate their similarities for providing recommendations. Traditional soil tests, ion exchange membranes and analyses using the Haney Soil Health Nutrient Tool and Soil Health Index were compared for soil sampled from long-term cropping system trials near Ritzville Washington and from the R.J. Cook Agronomy Farm near Pullman WA. Despite strong... D. Huggins, C. Rieser, J. Reganold

7. Compost Application in California Tomato Cropping Systems

With the implementation of California Assembly Bill (AB) 341 the availability of composts such as green waste (GW) and co-composted green waste and food waste (FW) as a soil amendment is increasing. The use of those organic amendments in agricultural production systems has been recommended as an effective strategy to make full use of organic waste and improve soil health. However, little information is available to tomato growers to reassess N inputs from using GW and FW. This study was condu... Q. Yi, W. Horwath, S. Haas, X. Zhu-barker

8. Cover Crop Suitability for High Altitude Specialty Crop Organic Food Production

There is a growing interest in certified organic, specialty crop food production. With a larger population demanding organic products and organic products offering a higher premium for the producer, farmers are exploring the transition to organic farming. Organic producers in southeatstern Wyoming face multiple challenges in environments with high elevation, low precipitation, and have a short growing season. These challenges include management of persistent weeds, maintaining biodiversity, a... E. Moore, U. Norton

9. Dairy Manure and Fertilizer Effects on Microbial Activity of an Idaho Soil

Dairy manure applications that have occurred in the past can have long-term lingering effects on crop production. Understanding the cause is important for current and future management practices. This study was conducted to assess selected microbial activity among past manure application rates.  In a past study (2014-2016) in Kimberly Idaho, historic manure applications have been shown to have significant positive and negative effects on sugar beet production. The manure treatment histor... D.D. Tarkalson, R. Dungan, D. Bjorneberg

10. Denitrifying Woodchip Bioreactor Performance in the Pacific Northwest

Runoff and tile drainage from agricultural activity is known to be a significant contributor of nitrogen pollution to surface waters.  Denitrifying woodchip bioreactors, also known as Permeable Reactive Barriers (PBR) have been studied as a possible edge-of-field technology for reducing nitrogen concentrations in agricultural runoff.  These units have been studied mostly in the US Midwest and mostly for irrigated crop systems.  Little work has been done in alternative climate r... E.M. Weisshaar

11. Developing a Soil Health Assessment Framework for Specialty Crop Systems and Soils of Washington State

To ensure productive soils, agricultural sustainability, and food security, it is vital to maintain and improve soil health. However, over the decades, intensive agricultural practices have led to a decline in soil health. While most of these intensive agricultural practices negatively affect soil health, research has shown that it is possible to resuscitate soils with practices such as over cropping, and crop rotation. Much of the research on soil health in the US has been done in agronomic ... K.A. Sarpong, M. Mcilquham, L. Michel, D. Griffin

12. Development of Leaf Sampling and Interpretation Methods for Almond and Development of a Nutrient Budget Approach to Fertilizer Management in Almond

A five year research project on the use of N in orchards crops has been conducted to 1) to develop early season sampling protocols, and 2) to determine the response of Almond to various rates and sources of nitrogen (N) and potassium (K) fertilizers, 3) to develop nutrient demand curves and 4) to conduct a long term assessment of nutrient use efficiency with the goal of improving fertilizer management. Leaf and nut samples were taken at 5 stages of development throughout five seasons to deter... P.H. Brown, S. Saa, S. Muhammad, B. Sanden

13. Differences in How Late Season Soil Vs. Foliar Nitrogen Fertilizer Supplements Affects Riesling Yan

During the 2011 and 2012 growing seasons, 0, 15, or 30 lbs/A N was applied in split applications as either soil (simulated drip) or foliar applications to a commercial Riesling vineyard with a history of low vine N. Each treatment was replicated 4 times. To assess the impact of the supplemental N applications on vine vigor, shoot lengths were measured weekly and pruning weights collected during the dormant season (2012/2013 pruning not yet conducted). Fruit was harvested within 2 days of comm... J. Davenport, M. Mccoy

14. Does Post-harvest Nitrogen Application Affect Blueberry Yield or Cold Hardiness?

In central Washington, nitrogen (N) management in blueberries typically consists of all N being applied prior to harvest.  For early cultivars, such as Duke, this means all fertilizer is applied before the end of June, leaving a long period of growth with no supplemental N.  To evaluate the potential for splitting N fertilizer applications into pre- and post-harvest timings, we conducted an experiment in a randomized complete block design with four replicates on a commercial ‘... J.R. Davenport, G.A. Hoheisel, L.W. Devetter

15. Drinking Water Nitrate and Irrigated Agriculture in California

Nitrate contamination of groundwater in California has led to new government regulation of agricultural practices in the state’s Central Valley (CV) and Central Coast Regions (CC, which includes the Salinas Valley). Regulations in 2007 were imposed on dairies in the Central Valley, but more recently, all irrigated farming in both regions has been targeted. These regulations require monitoring and reporting (e.g., of fertilizer and manure applications), nutrient management plans, and adh... S. Pettygrove

16. Dryland Organic Winter Wheat Improvement by the Inclusion of Composted Cattle Manure and Cover Crops

Organic agriculture in semi-arid environments can face several challenges in order to produce a successful crop.  These include nitrogen and phosphorus deficiencies, moisture limitations, and high weed competition.  Organic winter wheat (Triticum aestivum, L.)-fallow systems can be amended with composted cattle manure and with green manure from cover crops grown in the fallow phase to help increase wheat yields and quality.  Cattle manure can improve soil health with t... C. Helseth, U. Norton

17. Effect of Nitrogen Rate and Cropping System on Soil Nutrient Levels in a Long-term Study

Diversified continuous cropping systems in semi-arid regions of the northern Great Plains may enhance sustainability. A study initiated in 2000 in southwest Montana was designed to evaluate crop productivity and economic returns for no- till and organic rotations that included small grains, pulses, and oilseeds. Our specific objective presented here was to compare soil nutrient differences from 2004 to 2012, to learn if economically superior rotations were building or depleting soil nutrients... C. Jones, P. Miller, T. Rick, A. Mccauley

18. Effects of Lime and Micronutrient Amendments for Acidic Soils of the Inland Pacific Northwest

The soil pH of agricultural land in the inland Pacific Northwest has dropped precipitously from native soil levels of near 7.0 pH. Changes that were becoming evident in the 1980’s have reached critical levels, leaving tens of thousands of acres of previous prairie soil at pH under 5.0 and unable to grow an increasing number of aluminum-sensitive crops. Some farmers in the region are beginning to use lime application to neutralize soil acidity. However, pH changes and liming can als... R. Wieme, L. Carpenter-boggs, P. Carter, S. Van vleet

19. Effects of Semiarid Wheat Agriculture on Soil Microbial Properties: A Review

Agricultural management decisions on factors such as tillage, fertilization, and cropping system determine the fate of much of the world’s soils, and ... J. Norton, H. Rodgers, L. Van diepen

20. Efficient N Fertility and Irrigation Management in Vegetable and Berry Production

Nitrogen (N) fertility and irrigation management for vegetable and berry production has historically been done on an ‘agronomic’ basis, with the sole focus on producing the optimal crop. For these crops N fertilizer and water costs are a small portion of overall production costs, and an even smaller portion of crop value; consequently, these inputs have not been scrutinized as closely as they have been for lower value crops. However, throughout the West concern over environmental ... T. Hartz, R. Smith, M. Cahn

21. 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 effic... B. Geary, S.R. Fahning, B.G. Hopkins

22. Enhanced Efficiency Phosphorus Fertilizers

Phosphorus (P) is essential for plants. However, first-year phosphorus fertilizer uptake by plants is low, resulting in economic and environmental impacts. Developments with P Enhanced Efficiency Fertilizer (EEF) sources show improved uptake efficiency and increased yield and/or crop quality, while reducing environmental risk. Research with EEFs (including organic acids, maleic itaconic copolymer, and struvite) all show these improvements, especially when: 1) soil test P concentrations are lo... B. Hopkins, S.J. Kobza, C. Seely

23. Estimating Nitrogen Credits from Organic Matter Sources in Orchards

Orchard crops like almonds can effectively utilize different nitrogen (N) sources to meet the high annual N demand for fruit and tree growth. Different fertilizer formulations like urea ammonium nitrate, calcium ammonium nitrate, ammonium sulfate and potassium nitrate are widely and effectively used, and readily available for uptake. Yet, addressing N availability from organic matter sources in orchards, and in turn estimating appropriate N credi... S.S. Khalsa, P.H. Brown

24. Evaluating Cover Crops for Nitrogen Management in a Walnut Orchard

Cover crops provide numerous benefits in agricultural systems. From increasing soil water storage to reducing fertilizer inputs, quantifying cover crops benefits is crucial in nutrient management, crop productivity, environmental sustainability, and growers' adoption. The goal of this study was to quantify nitrogen (N) and carbon (C) inputs in a walnut  (Juglans regia L. 'Chandler') orchard that implemented three cover crop mixtures. The study site was a 5-year-old w... D. Zapata, X. Zhu-barker, K. Steenwerth, W. Horwath

25. 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 a... C. Evans, A. Moore, D. Sullivan

26. 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 condition... R. Smith, A. Blaylock, E. Ellison, C. Sanchez

27. Factors Influencing Efficacy of Elemental Sulphur Fertilizers

Elemental sulfur is a byproduct of fossil fuel production and produced in large quantities in both the US and Canada.  Fertilizers containing elemental S have a high S content and low manufacturing cost, but may not reliably meet crop requirements for S in the year of application due to the time required for elemental S to be oxidized.  The main factors influencing the oxidation rate of elemental S are particle size, particle dispersion and environmental conditions.  ... E. Bremer

28. Impact of an Enhanced Nitrogen Fertilizer (ESN) on Irrigated Crop Production in South Central Montana

Trials were conducted at the Montana State University Southern Agricultural Research Center in Huntley, MT using ESN (44% N, Agrium Advanced Technologies) in combination with urea (45% N) on three different irrigated crops: spring wheat, corn, and sugar beet. Each experiment was a randomized complete block with 4 replications using either 4 or 6 nitrogen rates in combination with 6 or 4 mixing ratios of ESN:urea, plus one unfertilized check for a total of 25 treatments. Urea and ESN were weig... K. Mcvay, K. Kephart, Q. Khan

29. Impact of Soil Health Practices in an Irrigated Agroecosystem

Regional farming practices in cold semiarid irrigated agroecosystems with short growing seasons are shifting to reduced tillage and overhead irrigation to stay economically viable, but more research is needed on the impact of soil health practices such as crop diversification, reduced tillage, and livestock integration on soil physical and chemical properties in these systems. A multi-year study from 2014-2020 in the Bighorn Basin of Northwest Wyoming used a three-crop rotation (diversificati... T. Vance, V. Crowe, J. Norton

30. Improving Corn Nitrogen Management Recommendations in the Northwest U.S.

The current nitrogen (N) fertilizer recommendations for corn in the  Northwest U.S. were developed from limited research (14 potential site-years) in the 1970’s and 1980’s.   New data is needed to improve N fertilizer recommendations.  Between 2010 and 2017, 17 N rate studies were conducted.  Fifteen site-years were conducted for corn grain and 9 site-years for corn silage. Research was conducted on diverse soil types, tillage systems, irrigation systems, ... D.D. Tarkalson, D.L. Bjorneberg

31. Inhibitors, Method and Time of Nitrogen Application for Improved Winter Wheat Production in Central Montana

The contribution of nitrogen (N) fertilizer to boost yield and improve quality is unquestionable. Inefficient use of applied N is economically significant and environmentally unsafe. Ammonia loss can exceed 40% of applied N. Nitrogen leaching is polluting wells. Use of urease and nitrification inhibitors along with appropriate timing and method of nitrogen application can reduce nitrogen loss, improve yield and quality of wheat. This experiment investigated the effect of timing and method of ... Y. Mohammed, T. Jensen, J. Heser, C. Chen

32. 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 ... A. Moore

33. Irrigation and Nitrogen Management Web-based Software for Lettuce Production

Lettuce growers on the central coast of California are under increased regulatory pressure to reduce nitrate loading to ground and surface water supplies. Two tools available to farmers to improve nitrogen use efficiency of lettuce are the quick nitrate soil test (QNST) for monitoring soil mineral nitrogen levels and weather-based irrigation scheduling for estimating water needs of the crop. We developed a web-based software application, called CropManage (https://ucanr.edu/cropmanage), to fa... M. Cahn, R. Smith, T. Hartz, B. Noel

34. Is Cover Crop Species Mixture and Diversity More Important at Building Soil Health than Shoot Biomass in a Semi-arid Region?

Cover crop mixtures (CCMs) as partial fallow replacements have the potential to increase soil health, yet long-term studies on CCMs, especially in semi-arid environments are relatively rare. An eight-year study at two locations in semi-arid Montana sought to evaluate the effect of functional group (N fixer, tap roots, fibrous roots, brassicacae) and species richness (2, 6, and 8 species in a mix) on a range of biological, physical and chemical soil parameters. Although several soil healt... P. Miller, C. Jones, C. Zabinski, K. D'agati, M. Housman, S. Tallman

35. 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 experimen... 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

36. 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 re... B. Verhoeven, A. Moore, D. Sullivan, M. Gonzalez-mateu

37. Long-term Soil Profile Acidification: Obvious and Hidden Dangers

Soil acidification is occurring in the dryland farming region of the Northwest. Historically, soil acidification in the surface foot has been characterized; however, potential acidification of subsoil is unknown. We examined soil acidification for soil profiles (0 to 5 ft) at the R.J. Cook Agronomy Farm (92 ac) for 17 years following conversion from conventional tillage to continuous No-tillage (NT). Surface soil depths (0-12 in) acidified under continuous NT to below 5. Surprisingly, subsoil... D. Huggins, S. Shiwakoti

38. 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. Ho... D.L. Cole, D.T. Heidenreich, S.H. Stapley, A.M. Lambert, R.L. Buck, B.G. Hopkins

39. 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 pr... O.S. Walsh, S. Shafian, D. Jayawardena

40. 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

41. Nitrogen Management in Blueberries

Three field trials were conducted in Corvallis, OR from 2006 to 2011 to evaluate nitrogen (N) fertilizer practices for establishment of highbush blueberry (Vaccinium corymbosum L.). In the first trial, planted in April 2006, we compared the effects of N fertigation (injection of fertilizer through a drip system) to conventional granular fertilizer application in ‘Bluecrop’ blueberry and found that fertigation produced more growth and less salt injury in young plants than gran... D. Bryla, O. Vargas

42. Nitrogen Management in Wheat

Yields for current wheat varieties are quickly approaching 200 bu/a in high yielding environments. There are many approaches to managing nitrogen in wheat production systems using a variety of products on the market today. Urea, ESN, Agrotain, Arborite, DCD and many other nitrogen products are available for making sound agronomic decisions. Once the wheat plant is grown at about Fekes 7.0 there is the quandary of making protein when hard red winters or DNS types are grown. Choices become endl... D. Howneck

43. 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) evalua... J. Deenik, C. Penton, B. Popp, G. Bruland, P. Engstrom, J. Mueller, J. Tiedje

44. Nutrient Efficiency Concepts for Phosphorus and Potassium

Two measures of phosphorus (P) and potassium (K) efficiency that are of interest to producers are agronomic efficiency (AE) and partial nutrient balance (PNB). Agronomic efficiency considers crop response to a nutrient addition while PNBmeasures nutrient removal to nutrient use. Proper evaluation of AE requires long term monitoring. A single, large application of P or K can, over many years, result in an AE similar to smaller, annual applications. A larger initial dose will inc... T. Murrell

45. Nutrient Management in Pecans

In the desert southwest, commercial pecan growers routinely apply supplemental nitrogen and zinc. Only 40% routinely apply phosphorus, and fewer use boron, iron, and copper. To evaluate nitrogen requirement, rates ranging from 130 to 390 lbs N/a were applied for three seasons in a mature orchard. Nitrogen treatments had little effect on leaf nitrogen concentrations, tree growth, or nut yield. The lower rate of nitrogen application was sufficient to keep leaf nitrogen levels in the sufficient ... J. Walworth

46. On-farm Trials and Statistics

New technologies have made on-farm research easier to do. On-farm research networks exist in several states and are also being run by some national programs. These networks are becoming more common. University and/or government agency scientists and educators typically provide statistical expertise. Historical guidance for experimental design has focused on the randomized complete block design (RCBD). Statistical analyses that can be run easily are for an RCBD conducted in one site and one ye... T. Murrell

47. Permanent Crops - Nutrient Management

In California, environmental regulations are rapidly expanding and moving into new areas of concern at a very rapid pace. Most recent requirements are based primarily on nitrogen and how it fits into a Nutrient Management Program (NMP). CCAs are being asked to assist growers in controlling nitrogen use to reduce/avoid its discharge to the environment. The Regional Water Quality Control Board of California classifies a discharge as lateral movement to surface waters or movement past the root s... K. Backman

48. 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 in... B. Hopkins, T. Blair, M. Hill, C. Ransom

49. Phosphorus and Potassium How Low Can You Go In Alfalfa?

Tissues testing whole alfalfa plants at harvest can more accurately direct nutrient decisions. Developing critical nutrient levels in-season improves recommendations and applications, saving producers time, expense and effort since many growers take samples for hay quality. These three experiments were designed as follows: 1) Phosphorus (P) Rate study with differing rates of P2O5 using monoammonium phosphate (MAP); including: 0, 30, 60, 120, 240 lb P2O5... S. Norberg, S. Fransen, J. Harrison, D. Llewellyn, L. Whitefield

50. 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 incuba... G. Mooso, T. Tindall, G. Hettiarachchi

51. Phytomanagement of Soluble Selenium and Production of Biofuel and Biofortified New Products

In many areas of the western US, excessive concentrations of soluble selenium (Se) in the environment can cause Se toxicity to biological organisms. The use of green plants to manage the soluble Se content in soils by plant uptake and biological volatilization has been considered as a cost-effective strategy. Importantly, the development of economically feasible remediation systems will encourage more widespread implementation of an integrated phytomanagement technology. The objective of this... G. Banuelos

52. 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 applie... B. Hopkins, L. Sutton, C. Ransom, T. Blair, J. Moody, K. Manning, S. Bergsten

53. 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 p... B. Hopkins, C. Ransom, T. Taysom, J. Lemonte

54. Reducing Nutrient Losses in Runoff from Furrow Irrigation

Few studies have comprehensively examined nutrient losses in runoff from furrow-irrigated fields, but the rising cost of fertilizer and finite nature of the resource encourages further research. A 2-yr experiment measured runoff losses of sediment, particulate P and N, and dissolved NO3-N, NH4-N, K, and reactive P (DRP) from fertilized, manured, or non-amended fields. Average nutrient losses were substantial, including 15.6 lbs ac-1 yr-1 dissolved N, P, and K and 73.6 lbs ac- 1 ... R. Lentz, D. Westermann, G. Lehrsch

55. Refining Nitrogen Management for Organic Broccoli Production

Specialty organic fertilizers used in organic vegetable production are expensive. So, from environmental and economic perspectives, growers want to maximize nitrogen (N) fertilizer use efficiency by the crop. This research was conducted to (1) determine sufficient N fertilizer rates for organic broccoli, (2) evaluate the efficacy of a specialty organic fertilizer (feather meal; 12-0-0), and (3) confirm the effectiveness of midseason soil nitrate analyses (0-30 cm) in determining appropriate s... D. Sullivan, R.E. Peachey, A. Donaldson

56. Reliability of Soil and Plant Analyses for Making Nutrient Recommendations

Nutrient management is dependent on the collection of soil and plant samples for analytical testing and assessment. The quality of the analytical test are subject to bias and precision of the measurements made by the testing laboratory. Failure to understand lab analyses uncertainty can lead to over confidence in the management recommendation. Test uncertainty varies by soil and plant test methods utilized and by performance capability of the testing laboratory. Generally soil methods that pr... R. Miller

57. Repurposing Zinc from Mining Tire Waste to a Fertilizer Resource

Zinc (Zn) deficiency is common on high pH soils when growing field crops like Corn, Barley and Wheat.  Not only are crop yields and quality limited by low Zn, but more importantly the dilution of Zn in food stuffs and, thereby, Zn deficiency in the human diet has become a major concern as recognized by the World Health Organization.  At the same time, there is a Global problem in proper repurposing/disposal of used tires that contain between 1-3% ZnO.  In fact, in Chile, t... K. Greer, J. Wiebe, E. Bremer

58. 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 optimiz... C. Rogers, G. Thurgood, B. Dari, J. Marshall, O.S. Walsh, K. Schroeder, G. Loomis

59. Reuse and Reclamation of Phosphogypsum

Phosphogypsum (PG) is a byproduct of phosphate fertilizer production.  It is produced when phosphate rock is treated with sulphuric acid during the manufacture of phosphoric acid, and is composed primarily of  gypsum (CaSO4.2H2O).  It is estimated that over 3 billion tonnes of PG have been accumulated in stacks worldwide and over 150 million tonnes are produced annually.  In North America, PG is stockpiled in stacks that can cover hund... C. Nichol

60. Seasonal Water Distribution in a Drip-irrigated Cabernet Sauvignon Vineyard

Seasonal irrigation is vital to sustainable production of wine grapes in inland Washington. Without supplemental irrigation there is not enough rainfall during summer months to sustain plant health and productivity. Our 5 year project evaluates the effects of several regulated deficit irrigation treatments on soil water distribution throughout the growing season and the subsequent effects on yield and fruit quality in both Cabernet Sauvignon (CS) and Concord grapes; with a focus on wine grape... J. Davenport, J. Stout

61. 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

62. Sidedress Nitrogen Management in Lima Beans

Different rates of sidedress nitrogen were applied to bush baby lima beans, with and without starter fertilizer and rhizobia inoculant in Yolo County, CA in 2012. Results documented that the use of starter fertilizer (nitrogen, phosphorus, and zinc) significantly enhanced yields compared to control plots without starter fertilizer. Use of rhizobia inoculant at planting did not result in enhanced yields compared with no inoculant. Sidedressing with ammonium sulfate at 20, 40, 60 and 80 lbs/acr... R. Long, R. Meyer

63. 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 applica... A. Moore, M. Satterwhite, J. Ippolito

64. Soil Health and Ecological Resilience on the Palouse

Healthy soil is critical for global food security and other essential ecosystem services but is threatened by processes of soil degradation, with at least 33% of global croplands estimated to be moderately or highly degraded. Current soil health assessments provide insight into soil functional performance but often lack diagnostic criteria that assess management effects on soil function over time. We integrate soil health assessments with ecological resilience theory to better understand mana... A.G. Davis, D.R. Huggins, J.P. Reganold

65. Soil Health Changes Following Transition from an Annual Cropping to Perennial Management-Intensive Grazing Agroecosystem

Management-intensive Grazing (MiG) on irrigated, perennial pastures has steadily increased in the western US due to pressure for reducing public lands grazing, overall declining land available for pasture, and decreasing commodity prices. However, there are still many unknowns regarding MiG and its environmental impact, especially with regards to soil health. Over a two-year period, we studied changes in soil health under a full-scale, 82 ha pivot-irrigated perennial pasture system grazed wit... J. Ippolito, C. Shawver, J. Brummer, J. Ahola, R. Rhoades

66. 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) ... R. Ghimire, S. Salehin

67. Soil Phosphorus Availability Differences Between Sprinkler and Furrow Irrigation

Water flowing in irrigation furrows detaches and transports soil particles and subsequently nutrients such as phosphorus (P). To reduce the risk of erosion and offsite P transport, producers in south-central Idaho have been converting from furrow to sprinkler irrigation. We completed research on soil P dynamics in furrow versus sprinkler irrigated soils from four paired-fields in the region. Surface soils (0-2.5 inches) were obtained from fields in September following barley harvest. Furrow i... J. Ippolito, D. Bjorneberg

68. Soil Test Interpretation: Saturated Paste, EC, SAR and CEC

Soils of neutral to alkaline pH of the Western United States often contain elevated levels of soluble salts and / or higher concentrations of sodium.  Elevated concentrations of soluble salts limit crop growth and sodium may impact water management.  Competent agricultural management of these soils is dependent on laboratory analysis of: soil soluble salts and there composition and the irrigation water soluble salt constituents.  Soil analysis based on the satura... R. Miller

69. 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/place... S. Stapley, B. Hopkins

70. Static Range Nitrogen Management in Northwest U.S. Sugarbeet Production

Nitrogen (N) management is important in sugarbeet production. This paper presents data to support a shift from a yield-based N management approach to a static range N management approach in the Northwest U.S. Production data and research show that yield-based N management can result in over application of N. Past research has been critical to improving and understanding sugarbeet N nutrition. However continued research is needed so cumulative data can be evaluated to improve management practi... D. Bjorneberg, D. Tarkalson, D. Olsen

71. Stratified Nutrient and Soil pH Education and Demonstration Project

Columbia County Washington is in the foothills of the Blue Mountain Range and the edge of the Palouse wheat country. The farming region soils are mostly a rich silt loam having a rainfall ranging from 10 inches in the north at the Snake River to 25 inches next to the Blue Mountains. About 90% of the cropping systems have migrated to some variation of conservation or reduced tillage. This has been good for the management of soil erosion but earlier intense soil sampling indicates that it may h... P. Carter

72. Sugar Beet Lime Effects on High pH Soils and Crops in Northwest U.S.

A viable solution to dispose of sugar beet precipitation calcium carbonate (PCC) is needed due to the unsustainable issues associated with storage. Sugar beet PCC is a lime material produced as a waste product from extracting sugar from sugar beet. The three main sugar beet processing factories in the Amalgamated Sugar Company growing area in Idaho and Oregon have stockpiled approximately 11.3 million Mg of PCC.  Each year these three factories produce a total of 350,000 Mg annually. &nb... D.D. Tarkalson

73. The Elasticity of Biochar Across the Farm: Nutrient Capture, Compost Feedstock, and Soil Amendment

When biomass is thermochemically altered through pyrolysis, what results is biochar, a solid, porous material that is high in carbon (C) (e.g. 80%).  Owing to its unique physicochemical properties, biochar has been evaluated as a soil amendment, a compost feedstock, a means to mitigate nutrient loss and a way to sequester carbon.  Biochar is an appealing material as a farm management tool because its potential use is varied.  As part of a Western SARE grant, soil scientists at ... N. Stacey, D. Collins

74. The Fertilizer Recommendation Support Tool (FRST) Initiative: National Survey on Soil Fertility Recommendations and Correlation/Calibration Database

Soil fertility testing is an integral tool used in nutrient management planning, providing information needed to determine where nutrients are required and how much to apply. While a great deal of effort has been successfully invested in standardizing soil test methods in the U.S. over the last few decades, up-to-date correlation/calibration studies are lacking in many states. In most cases, soil test correlation/calibration efforts lead by land-grant universities are on a state-by-state or l... S.E. Lyons, J.T. Spargo, D.L. Osmond, A.W. Pearce, N.A. Slaton, D.K. Arthur, P.J. Kleinman, J.M. Mcgrath

75. Twenty Years of Cotton Nitrogen Management and Cycling Trials in the Southwest: What Have We Learned?

Over 20 site-years of nitrogen fertilizer management and cycling trials have been conducted in Lubbock Texas and Maricopa Arizona from 1998 to 2019.  Furrow, overhead sprinkler (OSI), subsurface drip irrigation (SDI) were used.  Soil profile nitrate (0-36 inches in Texas and 0-72 inches in Arizona) was sampled and tested for in all trials.  Nitrogen-15 labeled fertilizer was used for two years in Texas and for two years in Arizona.  Canopy reflectance was measured in every... K.F. Bronson

76. Use of Non-replicated Observations and Farm Trials for Guiding Nutrient Management Decisions

Replication or repetition is the means by which experimental error is estimated in replicated trials. In farm trials, it is sometimes not possible to replicate demonstration and test plots due to manageability and costs. In these situations, non-replicated observations and on-farm trials are used. In addition, nutrient response studies are often needed to calibrate the fertilizer requirement of a field. In this paper, we will define on-farm trials and observations, discuss the nature and unde... S. Machado, K. Girma

77. Using Irrigation Nitrogen Credits for Grain Crops

Nitrogen contamination of surface and groundwater is not uncommon in many areas of the U.S. and Colorado is no exception. Nitrate-nitrogen (NO3-N) in groundwater is the most common form of plant available nitrogen (N), especially in shallow, alluvial aquifers in areas with intensive irrigated agriculture. When utilized as a primary irrigation water supply, this nitrate can contribute a significant portion of a crop’s N supply. Crediting water nitrate is part of Colorado N fertilizer rec... T. Bauder, R. Waskom

78. Vineyard Soil Health: What Soil Properties are Most Important?

Washington is the second leading producer of wine grapes (Vitis vinifera) in the US, with over 60,000 acres in vineyards. With such a substantial acreage, it is crucial to know how management practices may affect soil and vine health in wine grape systems. Soil health indicators and threshold values have been extensively studied in commodity crops in the Midwest and the northeastern US, but there is much less information available for specialty crops in the Pacific Northwest. &... M. Mcilquham, D. Griffin-lahue, K. Sarpong, L. Michel