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2011
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Authors
Andrews, N
Andrews, P
Backman, K
Bair, K
Banuelos, G
Battany, M
Bauder, T
Bergsten, S
Bjorneberg, D
Blair, T
Blaylock, A
Bronson, K
Brown, B
Brown, P.H
Bruland, G
Bryla, D
Cahn, M
Carpenter-Boggs, L
Carr, C
Carter, P
Chahine, M
Chen, C
Clough, G
Collins, H
Costello, R
Datta, R
Davenport, J
Deenik, J
Dellavalle, N
Dungan, R.S
Eckhoff, J
Ellison, E
Engstrom, P
Falen, C
Fife, T
Flynn, R
Ghimire, R
Girma, K
Goosey, H
Granastein, D
Greenwood, M
Greer, K
Halvorson, A
Hammermeister, E
Harbertson, J
Hartz, T
Hatfield, P
Heerema, R
Heser, J
Hettiarachchi, G
Hicks, D
Hill, M
Hines, S
Holcomb, J
Hopkins, B
Horneck, D
Howneck, D
Hunsaker, D
Ippolito, J
Jensen, T
Jolley, V
Jones, C
Julian, J
Kephart, K
Khan, Q
Lauriault, L
LeMonte, J
Lehrsch, G
Lenssen, A
Lentz, R
Leytem, A.B
Lindemann, W
Long, R
Machado, S
Manning, K
McCauley, A
McClellan, T
McCoy, M
McGuire, A
McVay, K
Meyer, R
Miller, P
Miller, R
Mohammed, Y
Mon, J
Moody, J
Moore, A
Mooso, G
Mueller, J
Muhammad, S
Murrell, T
Noel, B
Norell, R
Norton, J
Novak, J
Nunez Moreno, H
O'Geen, T
Owens, J
Pasakdee, S
Penton, C
Petrie, S
Pettygrove, S
Pool, K
Popp, B
Ransom, C
Reddy, K
Reeve, J
Reganold, J
Rick, T
Riley, B
Saa, S
Sainju, U
Sanchez, C
Sanden, B
Satterwhite, M
Smith, R
Smithyman, R
Snyder, E
Southard, R
Spokas, K
Steiner, R
Sterubel, J
Stevens, K
Stougaard, B
Stout, J
Strik, B
Sullivan, D
Summerhays, J
Sutton, L
Taysom, T
Tiedje, J
Tindall, T
Vargas, O
Walworth, J
Wang, G
Wann, A
Waskom, R
Webb, B
Weeding, J
Wenzel, C
Westcott, M
Westermann, D
Wildfong, D
de Haro Marti, M
leMonte, J
Topics
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Oral
Year
2011
2013
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Year

Filter results69 paper(s) found.

1. Advances in Nutrient Use Efficiency

The improvement of fertilizer efficiency is driven by narrow profit margins, environmental concerns, and resource conservation. Fertile soil is the foundation for food production and successful civilizations; it is developed and maintained through the addition of nutrients lost through harvest. However, nutrient uptake by plants is inherently inefficient and the nutrients remaining in the soil after uptake can cause negative air and water resource impacts. In addition, poor fertilizer efficie... B. Hopkins

2. 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

3. Ammonia Volatilization

Little work has been reported on the loss of ammonia from soils where fertilizers have been applied in an undisturbed environment. There are a multitude of studies that have used a chamber of some sort to estimate ammonia loss. The use of a chamber of some sort means that the environment has to be altered making the data derived suspect when translated into a loss number such as kg/ha. The advent of passive vertical flux method by Wood et al., 2000 at Aubrn University in Alabama, allows for t... J. Holcomb, D. Horneck, G. Clough, D. Sullivan

4. An Excel Based Workbook for Assisting with Water Quality Interpretations

Clientele using the NMSU Soil, Water, and Agricultural Testing laboratory, as well other commercial labs, are usually given an irrigation water interpretation guideline in the form of a table with acceptable ranges. This approach, while helpful, does not quickly identify areas of concern to the client nor does it assist with estimating leaching fractions when salinity levels are high enough to warrant reclamation. A Microsoft Excel based workbook was developed to assist professionals and clie... R. Flynn

5. Biochar Usage: Pros and Cons

Soil fertility benefits of charcoal application have been reported as early as 1847 indicating that plant nutrients are sorbed within charcoal pores. The use of biomass-derived black carbon or biochar, the solid byproduct from the pyrolysis processing of any organic feedstock, has garnered recent attention as a potential vehicle for carbon sequestration and a beneficial soil conditioner. However, most of the past biochar research has focused on improving the physico-chemical properties of tro... R. Lentz, J. Ippolito, K. Spokas, J. Novak, H. Collins, J. Sterubel

6. Boron Fertilization of Chile Pepper Under Greenhouse Conditions

Many chile (Capsicum annuum) growers apply boron (B) without knowing if B is actually needed. The application of B has been suggested to improve specific conditions that limit chile productivity such as alleviating blossom-end rot. Two varieties of chile were grown (159 days) under greenhouse conditions in silica sand and irrigated with seven levels of B (no B, 0.025 mg L-1, 0.05 mg L-1, 0.1 mg L-1, 0.25 mg L-1, 0.5 mg L-1, 1.0 mg L-1) and complete nutrient solution. Leaf B increased linearly... W. Lindemann, R. Flynn, C. Carr, R. Steiner

7. Choosing Your Nitrogen Fertilizers Based on Ammonia Volatilization

Until recently we have not been able to measure ammonia volatilization without impacting the surrounding environment. In the past we have used closed chambers with acid traps. These closed chambers did not reflect surrounding weather conditions, at the minimum both temperature and wind were influenced. The use of the vertical flux method allows ammonia in the air to be monitored and modeled to reflect ammonia loss without any interference of the surrounding environment. ... D. Sullivan, D. Horneck, J. Holcomb, G. Clough

8. 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

9. Cover Crops for Nitrogen Management in Irrigated Cropping System

In perennial fruit cropping systems, the inter-row offers on opportunity to grow a cover crop that then can be used to supply nitrogen (N) to the fruit crop. We conducted research in both Concord grape and Gala apple to evaluate the potential of cover crops to supply N to the crop. Based on continuous monitoring of plant available NO3-N by using PRSTM ion exchange resin probes, we found that in Concord grape, while both hairy vetch and yellow sweet clover did not release quite as much N ... J. Davenport, K. Bair, D. Granastein

10. Crop Management Effects on Nitrous Oxide Emissions from Irrigated Systems1

The paper objective is to present an overview of the greenhouse gas research results from tillage and N fertility studies conducted by USDA-ARS on irrigated cropping systems near Fort Collins, Colorado from 2002–2010. Within agronomic N rates needed to optimize irrigated crop yields in the Central Great Plains, a linear increase in growing season nitrous oxide (N2O-N) emissions was observed from a clay loam soil with increasing fertilizer N rate. Averaged over a 5 yr period (2002-2006),... A. Halvorson

11. Deficit Irrigation in Vineyards of Washington State

In Washington State the primary wine grape producing areas lie within the rainshadow of the Cascade Range and receive little precipitation throughout the year and especially during the summer. Wine grape producers take advantage of the arid conditions and use irrigation management to control vine growth and vigor. The precise control of irrigation timing and amount also affects the wine making characteristics of the fruit produced. A Cabernet Sauvignon (Vitis vinifera L) vineyard was use... B. Riley, R. Smithyman, J. Harbertson

12. Delivery of Soil Science to Farmers Using Advanced Simulation Tools: a 10 Year Case Study

Technologies that aid in farm management and input application can increase profitability only if they readily show an advantage that the farmer can measure (Walton 2010). Western Ag Labs Ltd. (WAL) is a soil science laboratory which provides an educational soil service to producers of Western Canada using the PRSTM Technology. The service provides their customers access to advanced simulation tools that serves as a decision support system for Crop Nutrition Planning (CNP). The PRSTM technolo... K. Greer, D. Wildfong, D. Hicks, E. Hammermeister

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

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

14. 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

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

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

16. 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

17. 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

18. 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

19. Effectiveness of Soil-applied Zinc for Pecans

Pecan trees [Carya illinoinensis (Wangenh.) K. Koch] are very sensitive to Zn deficiency when grown in alkaline soils due to the formation of insoluble Zn hydroxides and carbonates which have low availability to pecan roots. We tested the efficacy of soil applied Zn-EDTA, Zn-Avail®, and ZnSO4 plus animal manure for supplying Zn to young pecans. Zn-EDTA supplied adequate Zn to potted pecan trees for one season only. The other soil Zn treatments had no appreciable effect. A soil s... J. Walworth, H. Nunez moreno, K. Stevens

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. Efficient N Management for High-yield Vegetable Production

Vegetable production is an N-intensive industry; rates of N fertilization can be very high, particularly where multiple crops per year are produced. In vegetable production areas across the country high nitrate-nitrogen (NO3-N) concentration in surface water and groundwater is focusing regulatory scrutiny on fertilization practices. Furthermore, escalating energy prices mean higher N fertilizer costs, making efficient N management an economic as well as an environmental necessity. The basic p... T. Hartz

22. Emissions of Ammonia and Greenhouse Gasses from Dairy Production Facilities in Southern Idaho

Idaho is one of the top three milk producing states in the United States. While this commodity group is a very valuable part of the economy, there is concern over the impact of these production facilities on the generation of ammonia (NH3) and greenhouse gases (methane, CH4 and nitrous oxide, N2O) which are linked to air quality degradation and global warming. To gain a better understanding of the on-farm emissions from these production facilities, we monitored both cattle housing and ma... A.B. Leytem, D. Bjorneberg, R.S. Dungan

23. Evaluation of Irrigation Application Management Practices to Protect Groundwater Quality

Agricultural management practices relative to irrigation application and type and frequency of nitrogen fertilizer application can impact levels of nitrates in groundwater. In recent history, high levels of nitrates were reported in public water supply wells in Goshen County, WY. Subsequent research efforts concluded that likely sources of nitrate were organic soil nitrogen and ammonium or nitrate fertilizer. Some focus was then turned to agricultural production higher up in the watershed. Be... K. Reddy, A. Wann, C. Wenzel

24. Evaluation of Soil Salinity Conditions in California Central Coast Winegrape Vineyards

Soil salinity conditions in the winegrape vineyard areas of the California Central Coast were assessed by regional surveys of surface soils over multiple years, and by comprehensive evaluations of deeper salinity profiles at select locations. The multiple-year survey indicated that salinity conditions were increasing significantly, during a period characterized by below-average rainfall for the region. The survey also indicated that salinity conditions were at levels which would be expected t... M. Battany

25. Evaluation of Soil-applied Eddha-chelated Iron Fertilizer for Use in Correcting Iron Deficiency Symptoms in Mature Pecan Trees in the Pecos Basin, New Mexico

Soils in the Pecos Basin of New Mexico are characterized by pH 7.5-8.5 and lime content 15-30%. Under these conditions pecan trees are prone to micronutrient deficiencies; pecan trees throughout the basin exhibit interveinal leaf chlorosis symptoms characteristic of iron (Fe) deficiency. In orchards where the Fe chlorosis symptoms occur, affected trees are typically scattered through the orchard in no apparent pattern. Foliar application of ferrous sulfate fertilizer sprays (as well as other ... R. Heerema, R. Flynn

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. Forecasting Crop Nutrition Needs Using the Plant Root Simulator (PRStm) Technology

Conventional soil testing is based on the premise that a chemical extraction will reflect the soil nutrient supply to plants. The shortfalls of this approach have been evidenced by the numerous studies conducted over the past 50 years aimed at improving soil test methods. Radiotracer studies in the 1960’s where pivotal in shifting thinking away from nutrient concentration and toward mechanisms of nutrient supply. Barber (1995) first coined the term soil nutrient bioavailability&nbs... K. Greer

28. Highbush Blueberry Response to Compost and Sulfur

Highbush blueberry is adapted to soils with high organic matter and acidic pH, and it is often grown in Oregon with coniferous sawdust as a soil amendment or mulch. Composts could provide an alternative to sawdust, but acidification is needed to overcome high pH. Our objectives were to (i) predict the quantity of acidity needed to reduce compost pH to 4.8 (ideal for blueberry), (ii) determine compost characteristics suited for blueberry, and (iii) evaluate plant growth response and soil pH re... D. Sullivan, R. Costello, D. Bryla, B. Strik, J. Owens

29. 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

30. Improving Phosphorus Use Efficiency with Carbond P

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

31. Influence of Dairy Manure Applications on Corn Nutrient Uptake

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

32. 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

33. 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

34. 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

35. K Fixation and Significance for Crop Production

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

36. Managing Alfalfa Under Low Water or Drought Conditions

There are several aspects to managing alfalfa during drought, or periods of limited irrigation, all of which apply whether or not the alfalfa is drought stressed (Lauriault et al., 2009). Most of these will be more related to stand longevity – helping the alfalfa to ride out the drought and still likely be productive once water is available again. The points covered in this session are: 1) Harvest Management; 2) Variety Selection; 3) Fertility; 4) Weed Management; 5) Water Management... L. Lauriault

37. Measured and Predicted Temporal Changes in Soil Nitrate-n Levels from Late Summer to Early Spring in Montana

Most soil sampling is conducted from August to November in Montana because of better soil sampling conditions and because it provides more time for growers to make fertilizer decisions prior to application. Fertilizer guidelines in Montana are based on spring nitrate-N levels in the upper 2 ft because they are more indicative of growing season available N than fall nitrate-N levels. It is not known how much nitrate-N levels change between late summer and spring, nor is it known what factors a... C. Jones, A. Lenssen, C. Chen, K. Mcvay, B. Stougaard, M. Westcott, J. Eckhoff, J. Weeding, M. Greenwood

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

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

39. 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

40. 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

41. 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

42. 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

43. 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

44. 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

45. 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

46. Organic Management Improves Soil Health and Strawberry Nutritive Value

Soils and strawberries from 13 matched pairs of organically and conventionally managed fields were assessed over two years. Available plant nutrients were generally similar under organic and conventional management except that organically managed soils contained more available Zn and B. Soil C, N, and biological parameters were much greater under organic management. Organically produced strawberries matched by variety were smaller and had greater dry matter content than conventionally produce... L. Carpenter-boggs, J. Reganold, J. Reeve, P. Andrews

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 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

50. 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

51. 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

52. 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

53. Polymer Coated Urea: Impacts on Water/air Quality with Surface Applicaton to Permanent Sod

Nitrogen (N) is the most commonly used fertilizer and is essential to sustain the world’s populations. However, inherent inefficiencies in the soil-plant system result in losses of N to air and water, which can result in environmental quality problems. Two permanent sod turfgrass sites were fertilized with coated and uncoated urea and compared to an unfertilized control at 224 lb-N/ac. The polymer coated urea (PCU) was Duration 45 CR®. Fertilization resulted in increased growth and ... B. Hopkins, J. Lemonte, J. Summerhays, V. Jolley

54. Predicting Plant-available Nitrogen Release from Cover Crop Residues

Improved methods are needed to estimate the timing and amount of plant- available N (PAN) release from cover crops. The OSU Organic Fertilizer and Cover Crop Calculator, a downloadable spreadsheet tool, assists agricultural professionals in estimating N fertilizer replacement value of organic inputs. We conducted a series of laboratory incubations with cover crop biomass incorporated into soil to determine: (i) speed of PAN release, (ii) amount of PAN release, and (iii) robustness of the OSU ... D. Sullivan, N. Andrews, R. Datta, K. Pool

55. 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

56. Regional Water Board Impacts on Vegetable Production in California

More than 300,000 ha of vegetable crops are produced annually in the coastal valleys of central California. In these valleys vegetable production dominates the landscape, and since most fields produce two or more crops per year the annual fertilizer input is very high. Not surprisingly, environmentally problematic levels of soluble phosphorus in surface waters, and nitrate-nitrogen (NO3-N) in both surface- and groundwater, are common. The Central Coast Regional Water Quality Control Board (WQ... T. Hartz

57. 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

58. 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

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

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

60. 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

61. Soil and Plant Analysis: How They Fit into a “Green” Nutrient Management Program

Environmental concerns are changing the face of agricultural fertilization across the nation and world. Both nitrogen and phosphorus have become the major concerns in this area with other nutrients, salts, and chemicals being discussed for future regulations. The focus of environmental regulation depends on the characteristics of different geographical regions. Soil, water, and tissue analyses are needed to meet application requirements as regulatory documents are being drafted and implemente... K. Backman

62. 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

63. 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

64. 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

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

... A. Mcguire

66. The Use of Biochar As a Fertility Amendment in Tropical Soils

Biochars made from modern pyrolysis methods have attracted widespread attention as potential soil amendments to improve plant productivity in the infertile soils of the tropics. Feedstock and pyrolysis conditions affect the physico-chemical properties of biochar with important implications for soil fertility and plant growth. Specifically, biochar volatile matter (VM) significantly affect soil inorganic nitrogen (N) status and ash content impacts soil elemental composition and pH. This paper ... J. Deenik, T. Mcclellan

67. 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

68. 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

69. Utilizing Food Processing By-products As a Soil Amendment: Soil Nutrient Availability

We studied the impact of food processing by-products which contain high moisture content, low pH, high total dissolved salts, and trace elements. The primary goal of this project was to develop best management practices for sustainable reuse of food processing by-products as a soil amendment on California farmlands. Quantifying soil nutrient availability from these by-products is critical to growers to carefully establish fertilizer replacement value to improve their crop nutrient use efficie... S. Pasakdee, N. Dellavalle