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1. Accumulation and Partitioning of Nutrients by Irrigated Sugar Beets During the Growing Season in Southern IdahoAmounts 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, mon... M. De, A. Moore, R. Mikkelsen |
2. Agronomic and Economic Comparison of Conventional and Direct-seeding in the Intermediate Rainfall ZoneThe predominant dryland cropping system in the low (<12 inch) and intermediate (12- 18 inch) rainfall areas of the Pacific Northwest (PNW) is winter wheat (Triticum aestivum L.) summer-fallow using conventional tillage. Tillage increases the rate of soil organic matter oxidation which has an adverse effect on soil physical, biological and chemical properties. A field experiment comparing conventional tillage-based summer- fallow with chemical summer-fallow and direct-seeding ... S. Petrie, S. Albrecht, D. Long |
3. Agronomic Biosolids Application Rates for Dryland Wheat Across a Range of Northwest Climate ZonesPredicting agronomic rates is important to derive optimum economic and environmental benefits from biosolids fertilizer applications. We conducted this research to 1) evaluate dryland wheat response to biosolids applications over a range of climate zones in the Pacific Northwest and 2) compare agronomic application rates predicted from yield curves with those predicted from published extension guidance. We applied a range of biosolids rates during the fallow year in ten on-farm dryland wheat ... A. Bary, D. Sullivan, C. Cogger |
4. Amending Acidic Soils for Sustainable Wheat ProductionSoils in the Inland Pacific Northwest region have been gradually declining in quality as the result of applications of nitrogen fertilizers, regardless of the nitrogen form. Soil test reports evaluated in the 1980’s and 90’s indicated this decline. Recent surveys have provided more extensive data that the pH decline is continuing. Soil test reports indicate that nearly 90% of soils have declined to below 5.2 pH (strong to very strongly acid) in the surface layer of the soil profil... P. Carter, G. Wegner |
5. Application of Ion Exchange Resin Membranes to Nitrate Testing in the WestResin membranes have been used since the 1960s to measure P supply from the soil. In the 1990’s the Plant Root Simulator (PRS®) probe was invented to further refine a method to measure N mineralization from soil organic matter. The functional measurement of soil N supply during incubation has been applied to both in situ measures and in lab research studies. Extending the PRS® measurements of N ‘intensity’ or flux to a meaningful number that a plant can utilize was a... K. Greer, E. Bremer, T. Sievers |
6. Best Management Practices (Bmps) for Ammonia Emissions Reduction from Animal Feeding Operations: a Colorado Case StudyAmmonia emissions from agriculture are a growing concern, in particular, in Colorado where nitrogen deposition in Rocky Mountain National Park has highlighted public concerns. Due to the high level of political pressure on agriculture to reduce its emissions, the agricultural community in Colorado has recently developed a Rocky Mountain National Park Ag Strategy for decreasing ammonia emissions from agriculture and nitrogen deposition in the park. The strategy includes the completion of a tho... J. G. davis, A. Elliott, N. Marcillac, J. Pritchett, C. Stewart, A. Mink |
7. Boron Fertilization in PotatoThe high value of potato (Solanum tuberosum L.), its inefficient rooting system and the low organic matter content of sandy soils on which potatoes are cultivated result in widespread application of boron (B) and other micronutrients. However, in times of cost trimming, B may become an omitted input regardless of soil test values. Further, soil tests for B may need to be updated for higher yields, better management or improved soil test methods. Russet Burbank potato was grown a... B. Webb, B. Hopkins, J. Ellsworth, V. Jolley, R. Callahan |
8. Can the “Diviner” Probe Help Explain Water Use by Field Crops?Farms in New Mexico rely on various methods of irrigation but primarily flood or sprinkler systems. Timing irrigations to meet crop water needs using regulated ditch systems is not based on the actual need of the crops. However, pressurized systems that utilize groundwater have the ability to be adjusted to deliver variable amounts of water. A survey of irrigation practices was done in the Pecos River Valley by installing tubes in fields of pecan, alfalfa, corn, chile, and cotton and scanning... R. Flynn |
9. Canola Roots of Water and Nitrogen Use Efficiency: New Lessons for PNW Wheat GrowersThe semi-arid inland Pacific Northwest (iPNW) has primarily produced wheat for 125 years due to favorable climate, soils, economics and policy drivers. Shifting drivers over the past decade related to energy, climate change, regional and global markets have created new opportunities for the integration of canola into iPNW wheat-dominated rotations. Traditional wheat grower mindsets required an agronomic reboot, forged by an understanding of canola vs. wheat physio morphology, an explosion of ... W. Pan, T. Maaz, I. Madsen, W. Hammac, M. Reese |
10. Cool Season Mineralization of Recalcitrant Organic N in Undisturbed Cores of Manured SoilsThe objectives of this study were to (1) quantify cool season N mineralization from recalcitrant organic N in soils with a long history of manure application and (2) examine the relationship between cool season recalcitrant organic N mineralization and a fall mineralizable N index. “Cool season” was defined as October to February for fields with winter crops and October to May for fields with no winter crops. Two in situ trials were conducted with undisturbed so... D. Moberg, D. Sullivan, R. Johnson |
11. Cover Crops and Compost Amendments for Organic Grape ProductionIncreased costs of fertilizers that rely on petroleum products coupled with increased pest control and transportation costs has prompted more management practices that can make use of local waste products and utilize cover crops to reduce purchased inputs. A burgeoning wine industry could benefit from organic production techniques; however, their effects on vine growth and grape quality have not been explored in New Mexico. Alternative vineyard floor management systems were evaluated for orga... A. Ulery, R. Flynn, R. Walser, M. Weiss, S. Guldan |
12. Cover Crops for Hop Production in Semi-arid ClimatesTilling interrows to control weeds is a common practice in hop production, especially in the Yakima Valley of Washington which receives 8 inches average annual precipitation and produces 74% of US hops. Dry, tilled interrows leaves topsoil prone to erosion and decreases soil organic matter over time. The goal of this three-year study is to determine cover crop species that would be profitable weed control alternatives to tillage for hop producers in semi-arid climates by providing ground cove... S. Del moro, J. Davenport, C. Jones |
13. Creating Prescription Variable Rate Irrigation and Fertilization Zones: Water and Nutrient Management InteractionsVariable rate irrigation (VRI) and variable rate fertilization (VRF) technologies allow irrigation and fertilization rates to be spatially customized. VRF is widely adopted, but VRI is an emerging technology with minimal adoption. As water is often the driving force in nutrient cycling, our overall objectives are to evaluate VRI influences on VRF and vice versa; and to combine these technologies to significantly increase crop yield and quality, conserve water, and minimize environmental impac... J. Svedin, N. Hansen, R. Kerry, R. Christensen, B. Hopkins |
14. Crop Genetic Variability for Nutrient Use Efficiency: Biological Foundation, and Case of Spring WheatRecent advances in plant molecular biology have elucidated the mechanisms by which plant species adapt to low-nitrogen and low-phosphorus environments. This has paved the way to new perspectives and strategies for breeding and genetic engineering: the design of low-nitrogen and low-phosphorus cultivars in order to optimize nutrients use efficiency and enhance economic and environmental sustainability. In this paper, we review the enzymatic activity of root hair-embedded transmembrane proteins... R. Nkoa ondoua, M. Etesami |
15. Determining Plant Available Nitrogen from Manure and Compost Topdressed on an Irrigated PastureComposting manure is a practice that is gaining acceptance as an environmentally sound manure management practice at large animal production operations. Composting produces a value-added product that enhances the fertility and physical properties of soil. During the composting process, nitrogen and phosphorus in the original feedstocks are converted through microbial activity into predominantly stable organic compounds, lessening the risk of loss of these nutrients into the environment. Compo... J. G. davis, T. Bauder, K. Corwin doesken, A. Elliott |
16. Developing a Soil Test Kit for Extension ProgrammingSoil and horticulture Extension programs are enhanced by hands-on and interactive activities. Readily available and inexpensive soil test kits can be useful in Extension programming in the classroom and the field. With the addition of a few extra supplies and tools, a complete kit can be created for Extension educators to use in horticulture and soil management programming. Five soil test kits from different manufactures were evaluated for both ease of use and accuracy. All kits inc... C. Youngquist, J. Norton, J. Harsh |
17. Developing Extension Guidance for Management Effects on Ammonia Loss: a Computer Simulation Modeling ApproachComputer simulation models provide insight into ammonia loss processes and the sensitivity of ammonia loss predictions to environmental and management variables. As an example of how a simple computer simulation model can inform the Extension guideline development process, the ALFAM (Ammonia Volatilization from Field-Applied Animal Slurry) model was used to estimate NH3 loss from surface- applied municipal biosolids: liquid (3% dry matter) and dewatered (22% dry matter). Model ... D. Sullivan |
18. Digital Tools to Improve Sustainable Agriculture PracticesVisualizations have been shown to promote learning and understanding and to aid in analysis and problem solving. Many concepts in agriculture are well suited to demonstrations that are used in classroom settings or part of training events. However, many demonstrations are difficult to seed in a large setting, or take more time than can be allotted. A series of demonstrations were either filmed or created in animation to provide a digital means by which trainers could more easily train their s... R. Flynn, J. Walworth, J. Davenport, A. Ulery, D. Bloedel, J. Gleason |
19. Do 1:1 Soil Extracts for Salinity Underestimate Leaching Fractions?Soil test laboratories often include 1:1 pH and salinity measures as part of their routine analysis. The saturated paste method is also a choice but may not be selected due to a higher cost associated with the procedure. Historical crop response to salinity has been largely carried out using the saturated paste extract procedure. Plant response estimates to salinity are based on the saturated paste method. Leaching fractions are determined from the saturated paste extract as well. Recommendat... R. Flynn, A. Ulery |
20. Effect of Cover Crops and Compost on Soil Water Availability in Organic Dryland WheatIn 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 cov... K. Adeleke, J. Reeve, E. Creech, I. Atoloye |
21. Effect of Management on Nitrogen Budgets and Implications for Air, Soil, and Water QualityNitrogen is a key nutrient for both national and global food security, and nitrogen inputs from organic and/or inorganic sources are essential to maintain sustainable and economically viable agricultural systems. The challenge with nitrogen is that it is very dynamic and mobile, and some forms are subject to biogeochemical transformations that contribute to atmospheric, surface and leaching losses. Although nitrogen provides important rural, national and global economic benefits, nitrogen los... J. Delgado |
22. Effects of a One-time Compost Addition on Soil Health in a Rainfed Dryland Organic Wheat SystemMaintaining 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 M... I. Atoloye, J. Reeve, A. Jacobson, E. Creech |
23. Estimating Non-Fertilizer Nitrogen ContributionsCalifornia growers are facing increasing pressure to reduce nitrogen (N) losses in crop production. However, growers also need to maintain high yield levels to remain competitive. This is only possible when N inputs from all sources can be quantified and fertilizer application rates can be adjusted accordingly. The major sources of non-fertilizer N include soil residual nitrate, nitrate in the irrigation water and N mineralized during the growing season from organic material, such as soil org... D. Geisseler |
24. Evaluating Potential Impacts of Land-applied Food Processing By-products on Soil Quality and Plant NutrientsFood processing canneries, especially those using raw fruit, nut, and vegetable- base materials, generate various types of by-products or non-hazardous wastes. The constituents of these wastes are dependent on the source of raw material and the substances associated with the canning processes. The use of land-applied non-hazardous wastes as an agricultural soil amendment is projected to rise because of public concerns regarding environmental impact and economic restraints of their disposal to... S. Pasakdee, N. Dellavalle |
25. Evaluation of N Uptake Analysis As a Tool for Determing Potato N StatusPlant 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 ... J. Stark, S. Love, C. Mcintosh |
26. Evaluation of Soil Tests for Potentially Mineralizable Soil Nitrogen in Snake River Plain Soils in IdahoSoil 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 re... C. Rogers |
27. Evolution and Utilization of the Smaf for Soil Health AssessmentsSoil degradation remains a global problem caused by many diverse factors. In response to this global need, farmers, ranchers, soil scientists, ecologists and many other groups interested in protecting, restoring, and/or enhancing our soil resources have recently begun to embrace the concept of soil health to achieve those goals. This presentation will focus on three critical points: (1) the modern concept of soil health did not spring up overnight, (2) critical milestones regarding soil quali... D. Karlen |
28. Fine Tuning Nitrogen Management Soil TestsRecent changes in environmental regulations have brought a renewed focus on residual soil nitrogen. Years ago when much of the N was broadcast or injected into cultivated fields there were relatively simple techniques to make reasonable estimates. In more recent times drip irrigation, fertilization, and non-till have complicated the techniques required to measure residual N. This is especially the case in deep rooted crops. This presentation will discuss using quantitative soil test... K. Backman |
29. Grain Protein Content and Composition of Winter Wheat Cultivars Under Different Levels of N and Water StressThis 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 Mar... A. Ross, C. Saint pierre, C. Peterson, J. Ohm, M. Verhoeven, M. Larson, B. Hoefer |
30. Groundwater Protection in California: Nitrogen Planning and ReportingConcern over the environmental consequences of nitrogen released into the environment from agricultural operations goes back at least to the 1970s. Through the federal Clean Water Act (1972) and various state laws dating to that same time period, government has had the power to regulate nitrogen use for decades. However, only in recent years have serious attempts to restrict agricultural N usage become widespread. In California several Regional Water Quality Control Boards have recently ... D. Muck, T. Hartz |
31. Improving Nitrogen Use Efficiency of Cool Season Vegetable Production Systems with Broccoli RotationsNitrate leaching in leafy vegetable production in the Salinas Valley, CA is a continuing problem. Increased levels of nitrate in groundwater resources affects the ability of municipalities to access drinking water that meet federal water quality standards. Regulations by the Central Coast Regional Water Quality Control Board are now requiring growers to improve nitrogen use efficiency (NUE) in production fields. In prior studies we found that above ground biomass nitrogen (N) at crop maturity... R. Smith, M. Cahn, T. Hartz |
32. Improving Phosphorus Use Efficiency: Right Rate, Timing, and Placement and Enhanced Efficiency Fertilizer Sources: Research SummaryPhosphorus (P) fertilization is essential for societal sustainability. However, plant P uptake is inefficient due to poor soil P solubility, especially for crops such as potato (Solanum tuberosum L.) plant due to relatively poor rooting efficiency and high demand. Phosphorus use efficiency (PUE) improves with the right rate, timing, placement, and with using enhanced efficiency fertilizer products (EEF). We have conducted several dozen studies over nearly two decades showing PUE is impro... E. Shipp, T. Hopkins, B. Hopkins |
33. Interagency Cooperation to Improve Nitrogen Management for Water Quality ProtectionAgriculture and water are inseparable in a semiarid region such as Colorado. Adequate clean water supplies for drinking, agriculture, industry, and recreation are critical for the lifestyle Coloradans enjoy. The Agricultural Chemicals and Groundwater Protection Program (ACGPP) was created by the Colorado legislature in 1990. The purpose of this unique program is to reduce the potential impairment of groundwater by agricultural chemicals have on groundwater and the environment by preventing gr... T. Bauder, E. Wardle, R. Wawrzynski, K. Mauch |
34. Irrigation Effects on N AvailabilityIrrigation is necessary for crop production in the western US where the climate ranges from Mediterranean to desert conditions. Management of irrigation can potentially have large effects on crop available N because nitrate-N readily moves with water and because soil moisture affects root activity and the uptake of N. Additionally, fertigation is commonly used to supply N to crops though the irrigation system. More efficient use of N can be achieved by assuring that an irrigation system has a... M. Cahn |
35. Is Protein Enough for Assessing Wheat Flour Quality?The quality of wheat products such as bread, bagels, noodles or pizza that consumers purchase is based on the flour quality used in production. Flours with different characteristcs are needed to produce different products and flour quality is important to produce a quality end product. However, at the initial stage of flour production, wheat is sold on a grain protein premium basis by farmers to elevators and eventually millers. In many years, higher protein (> 15% protein) wheat can bring... C. Reese, D. Clay, D. Beck, R. Englund |
36. Managing Potassium for Organic Crop ProductionAn 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 |
37. Manure Treatments Change Nitrogen Cycling in Soils Receiving Repeated Applications of Dairy-wastesOur 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 res... J. Norton, M. Habteselassie, J. Stark, B. Miller |
38. Measuring Ammonia Loss Using Field-scale and Laboratory TechniquesFollowing the surface application of urea to soil, there is the potential for nitrogen (N) loss from ammonia (NH3) volatilization until sufficient rain or irrigation has moved it into the soil. Many studies measuring NH3 loss have used laboratory and microplot field studies. The limitation of these techniques is that they do not represent NH3 loss under natural conditions because enclosures alter air movement, humidity, and soil and air temperature inside the chambers. However, they... A. Heinrich, D. Sullivan |
39. N Management Tools for Desert VegetablesOver the past two decades studies have been conducted to evaluate diagnostic tools and practices aimed at the development of more efficient N management in desert vegetable cropping systems. In all cases initial studies were conducted in small plots at University Research Farms. However, practices that were found to be promising were scaled up into large experiment-demonstration in commercial production fields. Studies show that while tissue tests were often reasonable diagnostic tools for N ... C. Sanchez |
40. Nebraska Nitrogen Management Present and FutureUniversity of Nebraska faculty have been refining their N rate recommendation procedure since the 1970s. At that time, they introduced a procedure for predicting soil nitrate-N availability and effect on subsequent corn N needs. In the 1990’s this procedure was refined based on 81 state wide N rate experiments. In 2003-2006 it was re-confirmed with 32 state wide irrigated corn trials. The current algorithm is the following: N need (lb/ac) = [35 + (1.2 x EY) - (8 x NO3- N ppm) - (0.14 x ... C. Shapiro, R. Ferguson, C. Wortmann, T. Shaver, B. Krienke, G. Hergert, B. Maharjan |
41. New Tools in Soil and Manure Test Information Interpretation in UtahAn effort is underway to update the USU Analytical Laboratory’s (USUAL) procedures and data presentation/interpretation capabilities. Modern database management tools and analytical instruments have, in many cases, gone under-exploited in reducing sample turn-around time, in improving data dissemination and interpretation, and in providing research and extension personnel with access to comprehensive historical and current trend data on soil fertility, and manure and plant analysis.... G. Cardon, J. Kotuby-amacher |
42. Nitrogen and Irrigation Water Interactions in Drought Stressed Kentucky BluegrassThere is increasing pressure in arid regions to conserve water, especially during drought. Turfgrass is the irrigated crop of greatest acreage in the United States and water use for irrigating turf is coming under scrutiny in urban ecosystems. The purpose of this study was to evaluate water use and growth of Kentucky bluegrass (Poa pratensis L.) under various irrigation and nitrogen (N) regimes. A study was conducted in an environmentally controlled growth chamber with established Kentuc... K. Russell, A. Hopkins, N. Hansen, B. Hopkins |
43. Nitrogen and Phosphorus Fertigation on PearsAvoiding over-application of nitrogen (N) and phosphorus (P) fertilizers and increasing N and P use efficiency on pear orchards have significant benefits on pear productivity and the environment. Split fertigation of N and P fertilizers and banding application of N and P fertilizers may increase the use efficiency of applied N and P fertilizers compared with our current N and P management system -- single broadcasting application of dry N and P fertilizers to the soil surface. A field experim... F. Yin, C. Seavert, J. Bai |
44. Nitrogen and Water Interactions: Crop Production Systems Case StudiesFarmers and urban land managers have to strike a tenuous balance between achieving plant growth goals while responsibly managing natural resources. Water quality and scarcity issues are prominent concerns, along with soil quality preservation and conservation of fuel and fertilizer resources. The purpose of this presentation will be to highlight case studies where water and crop management practices were considered together to improve the efficiency of resource use. Evidences of water scarcit... B. Hopkins, N. Hansen |
45. Nitrogen Availability and Use Efficiency in Corn Treated with Contrasting Nitrogen SourcesNitrogen (N) is required in relatively large quantities for corn production and is often the limiting nutrient for growth and high yield. Improved understanding of N cycling in agroecosystems is essential for increasing N use efficiency (NUE) and sustainable food production. The transformations between organic N and inorganic N form a central part of the internal soil N cycle. Utah farmers grow approximately 990,000 tons of silage corn annually, which provides important forage in livestock an... A. Kakkar, J. Norton, Y. Ouyang |
46. Nitrogen Budgeting for Tree CropsIn recent years, nitrogen (N) budgets and the 4 R’s approach (right rate, right time, right placement and right source) to N fertilizer management has been gaining more acceptance. In the N budget and 4 R’s approach, fertilizers are applied in proportion to demand and timed with periods of N uptake. As a result, demand is satisfied in a timely fashion avoiding the application in excess of uptake capacity. While N is required for all plant processes, it is the specific growth and d... S. Khalsa, S. Muhammad, P. Brown |
47. Nitrogen Cycling and Partitioning Under Alternative Organic Orchard Floor Management StrategiesOrganic orchard systems are a significant and growing component of Washington State agriculture, yet sustainable methods of nitrogen (N) fertility and weed management remain a challenge. Nutrient supply is dependent on decomposition and mineralization of organic matter, yet intensive cultivation commonly used to control weeds can disrupt biological processes and cause loss of organic matter. To address the often-competing goals of organic fertility and weed control, a number of alternative or... L. Carpenter-boggs, D. Granatstein, J. Reganold, L. Hoagland, M. Mazzola, F. Peryea, J. Smith |
48. Nitrogen Management and Water Productivity of Grain Crops Under Drought or Limited IrrigationThe 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 em... S. Evans, N. Hansen, A. Blaylock |
49. Nitrogen Mineralization of Dairy Manure in a Calcareous Soil Under Field ConditionsUnderstanding N transformations in fields receiving dairy manure applications is an important component of managing this nutrient source to maximize crop profitability and reduce environmental damage. The objective of this study was to determine the net N mineralization from field applied dairy cow manure to a Portneuf silt loam as affected by application rate, application frequency, and naturally fluctuating temperatures throughout the growing season. This study was conducted in a field loca... D. Graybill |
50. Nitrous Oxide Emissions: Assessment and Mitigation in Irrigated Cotton in the Western USANitrogen from fertilizers is a major source of the potent greenhouse gas nitrous oxide (N2O) in irrigated cropping systems. To date, N2O emission data is scarce for row crops in the Western USA, especially, the desert southwest, where seasonal irrigation quantities can exceed 40 inches. The objective of these studies was to assess the effect of N fertilizer management on N2O emissions from furrow-, overhead sprinkler-, and subsurface drip-irrigated (SDI) cotton (Gossypium hirsutum L.) in... K. Bronson, D. Hunsaker, K. Thorp, C. Williams |
51. No-till Grain Production in Wyoming: Status and PotentialIn dryland cropping systems, optimal yields require that nutrient supply matches the soil’s yield potential supported by available moisture. Conservation tillage systems that leave at least 30 percent of the soil surface covered by residue dramatically increase moisture retained in the soil compared to crop-fallow systems. This enables producers to plant two, three, or four consecutive crops, or continuously, without fallow, but water and nutrient needs are much more closely balanced wi... J. Norton |
52. Non-destructive Measurement of Perennial Crop N StatusLittle research has been conducted to evaluate the use on hand-held leaf meters as tools to assess plant N status in perennial crops. In this study, using replicated N rate plots in place for up to four years, we used two hand-held leaf meters (the Minolta SPAD meter and the Field Spec CM1000) to monitor tissue N status in apple and one meter (CM1000 only) in wine grape. In both crops, relationships were found between leaf meter readings and both fertilizer N rate as well as tissue N concentr... J. Davenport, R. Stevens, E. Perry |
53. Nutrient Cycling in Effluent-irrigated Soil (Mollisol) Planted to Tropical Grasses in a Tropical Island EnvironmentDairy 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 grass... R. Valencia-gica, R. Yost, G. Porter, R. Pattnaik |
54. Nutrient Lessons from Long-term Cropping System StudiesThe long-term efficiency of applied nutrients in agricultural soils depends not only on the efficiency of use by the immediate crop, but also on the efficiency of use for residual forms. However, determining this efficiency is difficult due to the slow turnover of residual forms, large soil nutrient reserves, and multiple processes controlling the fate and crop utilization of nutrients. Long-term cropping system studies are useful in this regard because they allow small changes to accumulate ... E. Bremer |
55. Nutrient Management in a Regulated EnvironmentLaws and regulations mandate nutrient management that good managers have long practiced or should have. Prior to governmental regulations, economics was a major regulator. However, high returns on nitrogen inputs led to over application, causing environmental issues and human health concerns, which led to legal regulation. The Federal Clean Water Act (CWA) and the California Porter-Cologne Act provide for regulation of pollution of surface waters, groundwaters, and wetlands. The statewide Wat... N. Dellavalle |
56. Optical Sensing for Nitrogen ManagementAlthough nitrogen (N) nutrition is as or more important than other nutrients, it has been largely ignored by those applying variable rate fertilizer (VRF) due to its loss potential for VRF applications that occur many weeks prior to crop need. Applications of N are best applied as close to crop uptake as possible in order to avoid leaching, denitrification, and other losses. Spatial variability for crop N need is often considerable due to differences in yield potential and, to a lesser degree... B. Hopkins, S. Stephens, A. Shiffler |
57. Phosphorus and Zinc Interactions in PotatoPotato production requires high soil phosphorus (P) application with potential negative environmental and nutrient uptake effects. Impacts of high available P on species in potato cropping rotations are not adequately understood, nor have the causes of reduced yield and quality from excess P been fully explored. Antagonistic interactions with cationic micronutrients such as zinc (Zn) are plausible explanations. Two hydroponic experiments were conducted with Burbank potato to elucidate P and Z... B. Webb, B. Hopkins, J. Ellsworth, S. Barben, B. Nichols, V. Jolley |
58. Phosphorus Dynamics and Wheat Response to Applied P in a Spatially Variable Environment1Considerable 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 |
59. Plant Available Silicon Application in Winter WheatMany studies throughout the world has shown that various crops have positively responded to silicon (Si) application in terms of plant health, nutrient uptake, yield, and quality. The study’ objective was to evaluate the effect of Si application rate and time on winter wheat growth and development, grain yield and grain quality. Results suggest that application of plant available silicon at 50% rate at either emergence or Feekes 5 appears to be more advantageous in terms of winter wheat... O. Walsh, J. Mcclintick-chess, S. Blanscet |
60. Polymer Coated Urea in Potato ProductionNitrogen (N) is the most important mineral nutrient in potato (Solanum tuberosum) production. Studies show a steady, but not excessive, supply of N is important for maximum tuber yield, size, and solids, as well as minimal internal and external defects. Although more costly and labor intensive dry broadcast applications, growers typically apply the majority of N through the irrigation water in-season in order to maximize yield components. A controlled release N fertilizer, in the form of poly... B. Hopkins, T. Taysom, A. Shiffler, S. Stephens |
61. Polymer Coated Urea: Meeting Plant Needs While Mitigating Environmental Impacts — Research SummaryFertile soil is the foundation of food production and is maintained by replacing nutrients lost in harvest or to the atmosphere and hydrosphere. Nitrogen (N) accounts for approximately half of global fertilizer inputs. However, N recovery by plants is inherently inefficient due to “leaks” in the system, causing air and water pollution. Additionally, poor fertilizer efficiency is a waste of natural resources and potentially reduces yields, crop quality, and grower profits. Nitrogen... S. Bartholomew, T. Hopkins, B. Hopkins |
62. Precision N Management: Field-scale Application of N Efficiency Indices in WheatPreliminary evaluation of precision agricultural technologies showed that on-combine grain yield and protein monitors show promise as useful tools to characterize site- specific variations in crop performance. Variable rate applicators were shown to be proficient at achieving targeted site-specific application goals. First year comparisons of uniform versus precision N management in hard red winter wheat showed that similar yield and protein goals were met with 20% less applied N in the field... D. Huggins |
63. Precision Sensing for Improved Wheat ProductionImproving nitrogen (N) use efficiency (NUE) from current 35-40% is important for growers’ sustainability and environmental quality. Unmanned Aerial Vehicles (UAVs) are proposed as an alternative to traditional field scouting for making crop management decisions. Precision sensors and cameras mounted on the UAVs provide high quality images which can be used to make fertilizer recommendations in-season based on crop nutrient status. A study was conducted at 5 locations in Southern Idaho i... O. Walsh, J. Marshall, J. Mcclintick-chess, S. Blanscet, C. Jackson |
64. Predicting Phosphorus Runoff from Calcareous SoilsStudies 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 pr... J. G. davis, R. Schierer, J. Zumbrunnen |
65. Preliminary Assessment of the Solvita-CO2 Test in Characterizing Management Effects on Soil Biological Activity in Some Soils of HawaiiThe health of agricultural soils depends to a great degree on management practices that promote soil organic matter accumulation. While total soil organic carbon (C) is the standard measure of soil organic matter, it changes slowly and does not provide a sensitive enough test to assess short term management effects on soil health. However, a key indicator of healthy soil is potential biological activity, which can be measured rapidly with soil testing via short-term carbon (C) mineralization ... J. Deenik, M. Loo |
66. Recent Advances in P Fertilizer Technologies—polymer Coatings and Avail TechnologyPhosphorus 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 |
67. Reducing Dairy Effluent Phosphorus Content Through Struvite ProductionForced precipitation of struvite (magnesium ammonium phosphate hexahydrate, MgNH4PO46H2O) 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 exis... J. G. davis, J. Ippolito, M. Massey, R. Sheffield |
68. Remote Sensing of Corn N Status with Active SensorsDetermining in-season corn (Zea mays L.) nitrogen (N) variability has been a research focus of agronomists for quite some time. One of the methods currently available to determine N variability in corn is remote sensing. Studies have shown that remotely sensed imagery can detect N variability in corn. However, this method can have some limitations, such as the timeliness in which this imagery can be acquired. Hand-held active remote sensing devices may overcome these limitations... D. Westfall, R. Khosla, T. Shaver |
69. Remote Sensing of Grape K Deficiency Symptoms Using Leaf Level Hyperspectral ReflectancePotassium (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 reflecta... D. Smart, M. Whiting, C. Stockert |
70. Removing Nitrogen, Phosphate, and Fecal Coliform from Dairy Effluent Using Multi-soil-layer (Msl) SystemsDairy 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 (Fec... R. Yost, R. Pattnaik, G. Porter |
71. Residual Phosphorus Effects on Alfalfa Seed Pollination and ProductionHigher available P that increases alfalfa biomass reportedly reduces alfalfa seed yield due to poorer pollinator visitation. Available P effects were evaluated in a three year (2004-06) study with in-row plant spacing (12”, 24”, 36” and 48”) at Parma, ID to investigate the mechanism for the yield decline. Plots differing in residual P from previously applied P were further enriched with 0, 25, 50, 75, or 100 lb P/A. Plots were split in the last year and a mix of foliar... B. Brown, J. Barbour |
72. Response of Spring Wheat to Varied Nitrogen and Water ApplicationsThis study’s objectives were to 1) determine the minimum N and water requirements for optimum wheat grain yield and quality; 2) develop a sensor- based system for identifying – and distinguishing between – N and water stress; 3) produce grower recommendations based on the developed model; and 4) improve grower adoption of efficient water and N application practices and enhance grower understanding of sensor-based technologies. This was the first year of the study, project wi... O. Walsh, J. Torrion, X. Liang, J. Mcclintick, S. Blanscet |
73. Science and Stakeholder Engagement on 4R Nutrient Stewardship, Sustainability and Nutrient Performance Indicators: a Recent Central to Eastern U.S. and Global PerspectiveFarmers and society are becoming more aware of the need to better protect water, air and soil resources. The focus of the International Plant Nutrition Institute (IPNI) is on responsible nutrient management and stewardship to support the needs of the growing human family. Since 2007, IPNI has been more actively engaged with university scientists, federal and state agencies, agribusiness associations, crop advisers, and nongovernmental partners to get more of the applied nutrients - especially... C. Snyder |
74. Slow Release N for Irrigated Hard Red Spring Wheat Yield and ProteinProducing furrow irrigated hard red wheat with acceptable protein is challenging because of limited N management options for increasing protein. Slow release N has potential for improving N use efficiency in furrow irrigated hard wheat by avoiding the effects of excessive early season N yet providing later N for protein enhancement. A two year study (2005 and 2006) was conducted at Parma, ID to evaluate different N rates (120, 180 and 240 lb/A) of ESN and dry urea preplant N sources for furro... B. Brown, R. Gibson |
75. Soil Biological Indicators of Soil Health for Soil Health AssessmentsSoil is one of our nation's most valuable resources that provides life-sustaining functions. Billions of organisms live belowground and perform critical soil processes to support plant, animal, and human health aboveground. By shifting our view of soils from an inert growing material to a biologically diverse and active ecosystem, we can help create more sustainable farms, ranches, and forests to provide the food and fiber for our rapidly growing population while protecting land, air and ... J. Moore kucera |
76. Soil Characteristics of New Mexico Vineyards: Management ImplicationsA growing viticulture industry in New Mexico has sparked a need to establish best management practices for the climate and soil conditions present across the state. A survey of soil and water characteristics in established New Mexico vineyards was performed so that appropriate management strategies could be developed and limitations could be identified. Soil nitrogen levels varied from low to high indicating potential problems. Plant tissue testing needs to be included in a phosphorus nutriti... R. Flynn |
77. Soil Management Assessment Framework Use for Identifying Soil Quality Changes in Irrigated AgricultureThe 820 km2 Twin Falls (Idaho) irrigation tract is part of the Natural Resources Conservation Service (NRCS) - Conservation Effects Assessment Project (CEAP). Furrow irrigation was initiated in the early 1900s but, since the 1990s, the NRCS Environmental Quality Incentives Program (EQIP) and other specialty projects have resulted in conversion of approximately 40% of the irrigation tract area to sprinkler irrigation. Most past CEAP research has focused on water quantity and quality, effe... J. Ippolito, D. Bjorneberg, D. Stott, D. Karlen |
78. Soil Testing to Improve Phosphorus Management on Intensive Vegetable Farms in HawaiiAccording to a recent survey of soil samples sent to the Agricultural Diagnostic Service Center (ADSC) at the University of Hawaii between October 2002 and September 2003, a majority of the samples showed soil test P (STP) levels in the high or excessive categories. Despite high soil test P, many farmers in Hawaii continue to apply P fertilizers. We began a project to evaluate soil P status on a range of vegetable farms throughout the state, to determine crop response to P fertilizers on soil... J. Deenik, S. Fukuda, R. Hamasaki, R. Shimabuku, R. Uchida |
79. Soil Water and Plant Canopy Sensor Technologies to Optimize Water and Nutrient UseIn many respects, agricultural technology is doing things now that were only imagined 20 to 30 years ago. Yet, grower tools that provide information and actionable knowledge on water and nutrient availability still remain a challenge. Clearly, rapid development of data transfer and processing platforms to date has provided rich maps of grower fields with overlays of location-specific information but their utility is still limited by our ability to accurately measure the parameters that are th... C. Campbell, N. Hansen, B. Hopkins, S. Evans, E. Campbell, A. Campbell, L. Rivera, D. Cobos |
80. Soil Zinc Application for Southwestern PecanPecan 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 s... J. Walworth, A. Pond, H. Nunez, B. Wood, M. Kilby |
81. Spatial and Temporal Variability in Wine Grape NutrientsLittle work has been done to address the extent of spatial and temporal variability in nutrients in wine grape vineyards. In this study, we assessed soil and plant nutrient distribution on a per vine basis, both spatially and temporally across two vineyards, a Ruby Cabernet vineyard in Sunraysia and a Cabernet Sauvignon vineyard in Coonawarra. Petiole tissue was collected at two growth stages: flowering and veraison. Berry tissue was collected at harvest. All samples were analyzed for the pla... J. Davenport, R. Bramley |
82. Sustaining Agriculture and the Environment Through Healthy SoilsSoil 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 c... S. Shafer |
83. Test Driving a New Nrcs Nutrient Budget Calculator for Nutrient Management Planning in CaliforniaIn executing its mission to aid landowners in making conservation improvements, the USDA-Natural Resources Conservation Service (NRCS) assists landowners in identifying their operation’s potential risks to natural resources, if any. For assessing a cropland producer’s nutrient management, determining whether their nutrient applications rates might be considered excessive or has a potential to load up soil levels is key. However, NRCS does not make prescriptive ... B. Gale, Z. Kabir |
84. The Performance of the Soil Health Tool in Irrigated Calcareous Soils of the Western U.S.The Soil Health Tool (SHT), utilizes an integrated approach to soil testing for quantification of soil health and estimation of available nutrients for crop growth. The SHT is designed to mimic nature’s approach, as closely as possible, in order to estimate soil nutrient availability in the laboratory. The test itself includes extraction with water to measure soluble nutrients (C, N, P), a soil microbiological measurement, and a weak organic acid extraction to mimic additional nutr... A. Leytem, A. Moore |
85. Tillage Effects on Phosphorus AvailabilityVertical stratification of phosphorus (P) has been documented in both no-till and reduced tillage systems, yet very few studies have determined if this stratification has affected P uptake, and none of these studies have been conducted in Montana. Stratification of P was compared in 1.2 in layers in a small plot study composed of four tillage systems: long-term conventional (sweep) till (CT), 10-yr no-till (NT), 1-yr NT and 1-yr CT. Olsen P was measured in the upper 12 in., and a sequential e... C. Jones, K. Neill, C. Chen, E. Allison |
86. Urea and Ammonia Volatilization in Dryland Grass Seed Systems1The 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 burne... R. Koenig, C. Proctor, W. Johnston, C. Golob |
87. Variability of Manure Nutrient Content and Implications for Manure Sampling ProtocolThe variability of manure nutrient levels within and across farms makes manure sampling and development of reliable tabular values challenging. The chemical characteristics of beef, dairy, horse, sheep, and chicken solid manures in Colorado were evaluated by sampling six to ten different livestock operations for each manure type and comparing the results to values found in the literature. Due to the semi-arid climate of Colorado, manure tends to be drier and have lower ammonium (NH4-N) levels... J. G. davis, K. Iversen, M. Vigil |