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Overland Flow And Erosion From Runoff Plots On A Mollisol In Northeast China, Shuai Chen, C. Lee Burras, Xingyi Zhang Jan 2017

Overland Flow And Erosion From Runoff Plots On A Mollisol In Northeast China, Shuai Chen, C. Lee Burras, Xingyi Zhang

Agronomy Conference Proceedings and Presentations

Soil erosion and rainfall-induced runoff are well studied although under field conditions remain somewhat enigmatic. This study quantifies the relationship between rain, overland flow (runoff), erosion and size characteristics of the sediment in China’s northern “corn-belt” during the 2016 growing season. The study site was at the Heilongjiang Experimental Farm (47º23′N, 126º51′E), which is located near Guangrong village in China’s core Mollisol region. Two tillage treatments were evaluated: no-till and conventional till. Each treatment was replicated on runoff plots having 5° (9%) and 7° (12%) slopes. The 5° plots were established in 2006. The 7° plots ...


Active-Optical Reflectance Sensing Evaluated For Red And Red-Edge Waveband Sensitivity, Gregory M. Bean, Newell R. Kitchen, James J. Camberato, Richard B. Ferguson, Fabián G. Fernández, David W. Franzen, Carrie A. M. Laboski, Emerson D. Nafziger, John E. Sawyer, Peter C. Scharf, James S. Schepers, John F. Shanahan Jan 2017

Active-Optical Reflectance Sensing Evaluated For Red And Red-Edge Waveband Sensitivity, Gregory M. Bean, Newell R. Kitchen, James J. Camberato, Richard B. Ferguson, Fabián G. Fernández, David W. Franzen, Carrie A. M. Laboski, Emerson D. Nafziger, John E. Sawyer, Peter C. Scharf, James S. Schepers, John F. Shanahan

Agronomy Conference Proceedings and Presentations

Uncertainty exists with corn (Zea mays L.) N management due to year-to-year variation in crop N need, soil N supply, and N loss from leaching, volatilization, and denitrification. Active-optical reflectance sensing (AORS) has proven effective in some fields for generating N fertilizer recommendations that improve N use efficiency. However, various sensors utilize different wavebands of light to calculate N fertilizer recommendations making it difficult to know which waveband is most sensitive to plant health. The objective of this research was to evaluate across the US Midwest Corn Belt the performance and sensitivity of the red (R) and red-edge (RE) wavebands ...


Living Mulch Establishment In Row Crop Systems For Sustainable Biofuels Production, Cynthia Bartel, Andrew W. Lenssen, Kenneth J. Moore, David Laird, Sotirios V. Archontoulis Jan 2016

Living Mulch Establishment In Row Crop Systems For Sustainable Biofuels Production, Cynthia Bartel, Andrew W. Lenssen, Kenneth J. Moore, David Laird, Sotirios V. Archontoulis

Agronomy Conference Proceedings and Presentations

With increasing removal of maize (Zea mays L.) stover for cellulosic biofuels or livestock bedding and feedstuffs, there exists a need to ensure natural resources-related issues such as soil erosion, nitrate leaching, and loss of organic matter content are appropriately managed. Perennial groundcover offers a tenable solution for alleviating these problems associated with maize stover removal from conventional cropping systems. We conducted a field study to ascertain the expected cost of perennial groundcover establishment on the primary crop of economic interest and groundcover success under a maize or soybean (Glycine max L.) crop. To test this concept, we established either ...


Stacked Crop Rotation Reduces Soil Organic Carbon And Crop Yield Compared With Alternate-Year Rotation, Upendra M. Sainju, Andrew W. Lenssen, Brett L. Allen, William B. Stevens, Jalal D. Jabro Jan 2016

Stacked Crop Rotation Reduces Soil Organic Carbon And Crop Yield Compared With Alternate-Year Rotation, Upendra M. Sainju, Andrew W. Lenssen, Brett L. Allen, William B. Stevens, Jalal D. Jabro

Agronomy Conference Proceedings and Presentations

Stacked crop rotations and improved cultural practices have been used to control pests, but their impact on soil organic C (SOC) and crop yield are lacking. We evaluated the effects of stacked vs. alternate-year rotations and cultural practices on SOC at the 0- to 125-cm depth and annualized crop yields from 2005 to 2011 in the northern Great Plains. Stacked rotations were durum (Triticum turgidum L.)-durum-canola (Brassica napus L.)-pea (Pisum sativum L.) (D-D-C-P) and durum-durum-flax (Linum usitatissimum L.)-pea (D-D-F-P). Alternate-year rotations were durum-canola-durum-pea (D-C-D-P) and durum-flax-durum-pea (D-F-D-P). Cultural practices were traditional (conventional till, recommended seed rate, broadcast ...


Development Of Transformational Strategies Of Smallholders Based On Indigenous Knowledge, Mark E. Westgate, Lorna Michael Butler, Robert E. Mazur, Andrew W. Lenssen Jan 2016

Development Of Transformational Strategies Of Smallholders Based On Indigenous Knowledge, Mark E. Westgate, Lorna Michael Butler, Robert E. Mazur, Andrew W. Lenssen

Agronomy Conference Proceedings and Presentations

This presentation will outline a few of the key lessons learned during the first 12 years of extension programs implemented by the Center for Sustainable Rural Livelihoods (now the Iowa State University – Uganda Program, a Ugandan NGO). These lessons and recommendations are described in greater detail in “Tapping Philanthropy for Development”, L.M Butler and D. E McMillan (eds), Kumarian Press 2015.

Adhere to the Sustainable Livelihoods Approach.The CSRL initiative was developed to identify ways to improve the livelihoods of small landholder famers in rural communities of a developing country. Uganda was chosen because the vast majority of the ...


Impact Of A Corn-Living Mulch Cropping System On Soil C- And N-Dynamics, Chumki Banik, Cynthia Bartel, David A. Laird, Kenneth J. Moore, Andrew W. Lenssen Jan 2016

Impact Of A Corn-Living Mulch Cropping System On Soil C- And N-Dynamics, Chumki Banik, Cynthia Bartel, David A. Laird, Kenneth J. Moore, Andrew W. Lenssen

Agronomy Conference Proceedings and Presentations

Use of a living mulch in a continuous corn cropping system can potentially protect the soil from erosion and increase organic C inputs into the soil thereby enhancing soil quality and facilitating greater harvest corn stover for bio-energy production. The objective of this study is to evaluate soil C- and N-dynamics under a corn-living mulch system that includes a shallow rooted perennial cover crop, strip tillage, and spring burn down. This study hypothesized that a well managed shallow rooted perennial cover crop can improve soil quality by increasing soil C storage and synergistically distributing soil nutrients. Here we report impacts ...


Optimal Agricultural Practices For Growing Kenaf In Iowa, Marie Bourguignon, Kenneth J. Moore, Sotirios V. Archontoulis, Andrew W. Lenssen, Brian S. Baldwin, Danielle Marie Wilson Jan 2016

Optimal Agricultural Practices For Growing Kenaf In Iowa, Marie Bourguignon, Kenneth J. Moore, Sotirios V. Archontoulis, Andrew W. Lenssen, Brian S. Baldwin, Danielle Marie Wilson

Agronomy Conference Proceedings and Presentations

The demand for natural fibers is increasing worldwide due to a growing interest in using renewable sources in place of those derived from petrochemicals. Kenaf (Hibiscus cannabinus L.) is a promising biorenewable resource for natural fibers that has rarely been grown in the Midwest. Literature is abundant about effects of management practices on kenaf productivity and fiber yield, but few studies have evaluated their interactions. The objectives of this study were to: 1) determine management practices leading to optimal kenaf and fiber yield; 2) evaluate stem height, basal diameter, and leaf area index (LAI) over the growing season; and 3 ...


Adapted And Non-Adapted Tropical Corn In Central Iowa: 2. Biomass Production And Composition, Pedro A. Infante Posada, Kenneth J. Moore, Sotirios V. Archontoulis, Andrew W. Lenssen, M. Paul Scott Jan 2016

Adapted And Non-Adapted Tropical Corn In Central Iowa: 2. Biomass Production And Composition, Pedro A. Infante Posada, Kenneth J. Moore, Sotirios V. Archontoulis, Andrew W. Lenssen, M. Paul Scott

Agronomy Conference Proceedings and Presentations

Biomass production in the midwestern United States has largely been focused on corn (Zea mays L.) grain for ethanol production and more recently on corn stover for lignocellulosic ethanol. Corn production in this region is profitable and productive. As an alternative to conventional corn, tropical corn genotypes have been evaluated, but mainly for grain production; nevertheless, yields have fallen short of U.S. Corn Belt populations. Tropical corn is the term used for corn coming from tropical regions. Tropical corn has been adapted for early flowering for potential use in breeding programs under central Iowa conditions. Since adapted and non-adapted ...


Impact Of Nitrogen Application Timing On Corn Production, John E. Sawyer, Daniel W. Barker, John P. Lundvall Jan 2016

Impact Of Nitrogen Application Timing On Corn Production, John E. Sawyer, Daniel W. Barker, John P. Lundvall

Agronomy Conference Proceedings and Presentations

Water quality issues have renewed interest in timing of nitrogen (N) application as a means to improve use efficiency in corn and reduce losses. Improved economic return is also desired as N fertilization is one of the most costly inputs to corn production. Time of fertilizer application is a component of the site-specific 4R nutrient management stewardship programs. In Iowa, the Nutrient Reduction Strategy has a 7% (37% std. dev.) nitrate-N reduction with a 0% (3% std. dev.) corn yield change for sidedress compared to pre-plant N application (SP 0435A).


Adapted And Non-Adapted Tropical Corn In Central Iowa: 1. Development, Growth And Quality Aspect, Pedro A. Infante Posada, Kenneth J. Moore, Sotirios V. Archontoulis, Andrew W. Lenssen, M. Paul Scott, Shuizhang Fei Jan 2016

Adapted And Non-Adapted Tropical Corn In Central Iowa: 1. Development, Growth And Quality Aspect, Pedro A. Infante Posada, Kenneth J. Moore, Sotirios V. Archontoulis, Andrew W. Lenssen, M. Paul Scott, Shuizhang Fei

Agronomy Conference Proceedings and Presentations

Recent research has shown a high theoretical potential for ethanol production based on both stover and grain as sources, using lignocellulosic and fermentation processes respectively. Corn germplasm has been even broadly studied for grain production, but scant research has been done on current commercial cultivars in regards to biomass production. However, tropical corn germplasm, corn conventionally grown in tropical regions, has been studied as a potential source for biomass accumulation over grain. The comparison between tropical and temperate corn with a focus on biomass production has not yet been explored under Iowa day-length conditions.

This study identifies the adaptability of ...


Kenaf Productivity And Morphology. When Grown In Iowa And In Kentucky. Poster Number, Marie Bourguignon, Kenneth J. Moore, Andrew W. Lenssen, Sotirios V. Archontoulis, Ben M. Goff, Brian S. Baldwin Jan 2016

Kenaf Productivity And Morphology. When Grown In Iowa And In Kentucky. Poster Number, Marie Bourguignon, Kenneth J. Moore, Andrew W. Lenssen, Sotirios V. Archontoulis, Ben M. Goff, Brian S. Baldwin

Agronomy Conference Proceedings and Presentations

Natural fibers are a promising alternative to synthetic fibers for reinforcing plastic or other composite materials, or fuel purposes. Kenaf (Hibiscus cannabinus L.), a fiber crop is grown to a limited extent in the U.S. predominantly in the Southern states. Producing kenaf in the Midwestern U.S. could provide a local source of these fibers for use in a number of manufactured products and potentially for use as a biofuel feedstock. The objectives of this study were to: 1) compare the productivity and the morphology of kenaf cultivars ‘Tainung 2’ and ‘Whitten’ when grown in Iowa and Kentucky and ...


Crop Rotation And Cultural Practice Impact On Nitrogen Balance, Upendra M. Sainju, Andrew W. Lenssen, Brett L. Allen, William B. Stevens, Jalal D. Jabro Jan 2016

Crop Rotation And Cultural Practice Impact On Nitrogen Balance, Upendra M. Sainju, Andrew W. Lenssen, Brett L. Allen, William B. Stevens, Jalal D. Jabro

Agronomy Conference Proceedings and Presentations

Nitrogen balance provides a measure of agroecosystem performance and environmental sustainability by taking into accounts of N inputs and outputs and N retention in the soil. The objective of this study was to evaluate N balance due to N inputs and outputs and soil N sequestration rate after 7 yr in response to five dryland crop rotations (two 4-yr stacked and two alternate-year rotations and one monocropping) and two cultural practices arranged in a split-plot design in the northern Great Plains, USA. Stacked rotations were durum (Triticum turgidum L.)-durum-canola (Brassica napus L.)-pea (Pisum sativum L.) (D-D-C-P) and durum-durum-flax ...


Amino Acids And Biosynthesis Byproducts As Nitrogen Sources For Corn Production, Juan Carlos Quezada Rivera, Andrew W. Lenssen, Kenneth J. Moore Jan 2015

Amino Acids And Biosynthesis Byproducts As Nitrogen Sources For Corn Production, Juan Carlos Quezada Rivera, Andrew W. Lenssen, Kenneth J. Moore

Agronomy Conference Proceedings and Presentations

Byproducts resulting from the industrial synthesis of amino acids for feed-use might provide a significant supply of nutrients for crop production, particularly nitrogen (N). Iowa has a strong amino acid biosynthesis industry, resulting in a continuous supply of biosynthesis byproducts. Byproduct utilization as an N source for crop production may enhance revenues for amino acid producers and Iowa farmers. A field experiment was conducted in 2013 near Ames, IA, to evaluate corn (Zea mays L.) response to tryptophan (TRP) and lysine (LYS) biosynthesis byproducts as N sources. The objectives of this study were to determine corn response to isonitrogenous N ...


Root And Shoot Biomass And Nutrient Composition In A Winter Rye Cover Crop, Swetabh Patel, John E. Sawyer, John P. Lundvall, Jeena Hall Jan 2015

Root And Shoot Biomass And Nutrient Composition In A Winter Rye Cover Crop, Swetabh Patel, John E. Sawyer, John P. Lundvall, Jeena Hall

Agronomy Conference Proceedings and Presentations

Nitrogen loss from applied fertilizer can be a significant environmental quality issue if NO3 moves to surface or ground water. The Iowa nutrient reduction strategy science assessment identified winter cereal rye (Secale cereal L.) cover crop as a practice that can significantly reduce N and P loss (41% NO3-N and 21% P reduction) from corn (Zea mays L.) and soybean [Glycine max. (L.) Merr.] fields. Cereal rye, when used as a cover crop, through its fibrous root system is able to explore the soil and use residual NO3- N. In order to further understand the effectiveness of rye as a ...


Optimal Agricultural Practices For Growing Kenaf In Iowa, Marie Bourguignon, Kenneth J. Moore, Andrew W. Lenssen, Sotirios Archontoulis Jan 2015

Optimal Agricultural Practices For Growing Kenaf In Iowa, Marie Bourguignon, Kenneth J. Moore, Andrew W. Lenssen, Sotirios Archontoulis

Agronomy Conference Proceedings and Presentations

Replacing petroleum-based materials with renewable materials is of critical importance as we transition to a vigorous bioeconomy. The use of natural fibers derived from plants like kenaf (Hibiscus cannabinus L.), an annual herbaceous multi-purpose fiber crop, represents one way to address the economic and environmental problems associated with the use of synthetics. Although kenaf is adapted to subtropical areas and can be grown in temperate areas where corn is adapted, very few kenaf studies have been conducted in the Midwest, especially in Iowa, where kenaf could be a promising crop, if properly grown. This study focused on investigating planting date ...


Variety Trial And Pyrolysis Potential On Kenaf Grown In Iowa, Marie Bourguignon, Ken J. Moore, Robert Brown, Roger Hintz, Brian Baldwin Jan 2015

Variety Trial And Pyrolysis Potential On Kenaf Grown In Iowa, Marie Bourguignon, Ken J. Moore, Robert Brown, Roger Hintz, Brian Baldwin

Agronomy Conference Proceedings and Presentations

Kenaf (Hibiscus cannabinus L.) is a warm-season, herbaceous plant mostly used as a fiber-crop in the textile and pulp industry, but also has potential for lignocellulosic bioenergy. Midwest studies on growth and use of kenaf have been scant; however, kenaf may have potential as an alternative crop for Iowa and the Midwest. Seven kenaf varieties were grown in Boone County, IA between 2004 and 2007 and evaluated for their production potential in the Midwest. More specifically, our questions were: 1) how do kenaf varieties perform in Iowa for yield?, 2) how does fiber morphology and quality differ among varieties and ...


A Comparison Of Iowa's Original Corn Suitability Rating To The New Corn Suitability Rating 2, Aaron M. Sassman, C. Lee Burras, Gerald A. Miller Jan 2015

A Comparison Of Iowa's Original Corn Suitability Rating To The New Corn Suitability Rating 2, Aaron M. Sassman, C. Lee Burras, Gerald A. Miller

Agronomy Conference Proceedings and Presentations

In 1971 Dr. Thomas Fenton and several colleagues at Iowa State University (ISU) developed the Corn Suitability Rating (CSR) providing producers and assessors a soil productivity index for Iowa. The CSR for a soil is based on its inherent soil properties to a depth of 152- to 203-cm, mean weather data for a 30-yr period, and its potential for row crop production. In 1984 CSR data was combined with existing Soil Conservation Service (SCS) form SOILS-5 data, Map Unit Use File (MUUF), and Iowa CONS-9 data to create a single computer file of compiled soils data called the Iowa Soil ...


Mapping Agricultural Decision Making Across The U.S. Corn Belt, Tonya Haigh, Eugene Takle, Jeffrey Andresen, Melissa Widhalm, J. Stuart Carlton, Jim Angel Jan 2015

Mapping Agricultural Decision Making Across The U.S. Corn Belt, Tonya Haigh, Eugene Takle, Jeffrey Andresen, Melissa Widhalm, J. Stuart Carlton, Jim Angel

Agronomy Conference Proceedings and Presentations

Decision calendars help identify opportunities for inserting climate information into a decision process as well as points where other considerations might overrule use of the climate information. Developers of decision calendars are challenged, though, by a potentially infinite number of modifications required to address spatial variability in agricultural decision making. Variability in climate, soils, and agricultural production systems across a region may result in deviations in decision-making times.


Sheep Grazing Influence Soil Microbial And Particulate Organic Carbon In Dryland Cropping Systems, Upendra M. Sainju, Joy L. Barsotti, Andrew W. Lenssen, Zach J. Miller, Patrick G. Hatfield Jan 2015

Sheep Grazing Influence Soil Microbial And Particulate Organic Carbon In Dryland Cropping Systems, Upendra M. Sainju, Joy L. Barsotti, Andrew W. Lenssen, Zach J. Miller, Patrick G. Hatfield

Agronomy Conference Proceedings and Presentations

Sheep grazing may influence soil C fractions by consuming crop residue and weeds and returning C through feces and urine to the soil. We examined the effect of sheep grazing compared with tillage and herbicide application for weed control on soil microbial biomass C (MBC), potential C mineralization (PCM), and particulate organic C (POC) in relation to soil organic C (SOC) at the 0-30 cm depth in a Blackmore silt loam under dryland cropping systems from 2009 to 2011 in southwestern Montana, USA. Treatments were three weed management practices (sheep grazing [grazing], herbicide application [chemical], and tillage [mechanical]) and two ...


Dryland Soil Chemical Properties And Crop Yields Affected By Long-Term Tillage And Cropping Sequence, Upendra M. Sainju, Brett L. Allen, Thecan Caesar-Tonthat, Andrew W. Lenssen Jan 2015

Dryland Soil Chemical Properties And Crop Yields Affected By Long-Term Tillage And Cropping Sequence, Upendra M. Sainju, Brett L. Allen, Thecan Caesar-Tonthat, Andrew W. Lenssen

Agronomy Conference Proceedings and Presentations

nformation on the effect of long-term management on soil nutrients and chemical properties is scanty. We examined the 30-yr effect of tillage frequency and cropping sequence combination on dryland soil Olsen-P, K, Ca, Mg, Na, SO4-S, and Zn concentrations, pH, electrical conductivity (EC), and cation exchange capacity (CEC) at the 0-120 cm depth and annualized crop yield in the northern Great Plains. Treatments were no-till continuous spring wheat (Triticum aestivum L.) (NTCW), spring till continuous spring wheat (STCW), fall and spring till continuous spring wheat (FSTCW), fall and spring till spring wheat-barley (Hordeum vulgare L., 1984-1999) followed by ...


Dryland Malt Barley Yield And Quality In Response To Tillage, Cropping Sequence, And Nitrogen Fertilization, Upendra M. Sainju, Andrew W. Lenssen, Joy L. Barsotti Jan 2015

Dryland Malt Barley Yield And Quality In Response To Tillage, Cropping Sequence, And Nitrogen Fertilization, Upendra M. Sainju, Andrew W. Lenssen, Joy L. Barsotti

Agronomy Conference Proceedings and Presentations

Information is needed on the effects of management practices on dryland malt barley (Hordeum vulgaris L.) and pea (Pisum sativumL.) yields and quality. We evaluated the effects of tillage and cropping sequence combination and N fertilization on dryland malt barley and pea yields, grain characteristics, N uptake, and N use-efficiency from 2006 to 2011 in eastern Montana. Treatments were no-tilled continuous malt barley (NTCB), no-tilled malt barley-pea (NTB-P), no-tilled malt barley-fallow (NTB-F), and conventional-tilled malt barley-fallow (CTB-F), each with 0, 40, 80, and 120 kg N ha-1. As N rates increased, malt barley grain yield, protein concentration, and ...


Nitrogen Fertilizer Rate Effects On Soil Organic Carbon In Iowa Continuous Corn And Corn-Soybean Systems, Hanna J. Poffenbarger, Daniel W. Barker, Matthew J. Helmers, Fernando E. Miguez, John E. Sawyer, Johan Six, Michael J. Castellano Jan 2015

Nitrogen Fertilizer Rate Effects On Soil Organic Carbon In Iowa Continuous Corn And Corn-Soybean Systems, Hanna J. Poffenbarger, Daniel W. Barker, Matthew J. Helmers, Fernando E. Miguez, John E. Sawyer, Johan Six, Michael J. Castellano

Agronomy Conference Proceedings and Presentations

Nitrogen fertilizer rate is a key factor affecting soil organic C (SOC) in corn-based cropping systems. The objective of this study was to determine the change in SOC in response to long-term N rates for continuous corn and corn-soybean cropping systems at two sites in Iowa. Soil samples were collected to a depth of 15 cm in 1999 and again in 2014 after 15 years of corn N rate treatments ranging from 0 to 269 kg ha-1. The soil samples were analyzed for total C and N concentrations. For continuous corn at both sites, the average annual change in ...


Termination Timing And Biomass Removal: Impacts On Soybean Systems, Timothy Sklenar, Andrew W. Lenssen, Mary H. Wiedenhoeft, Thomas C. Kaspar Jan 2015

Termination Timing And Biomass Removal: Impacts On Soybean Systems, Timothy Sklenar, Andrew W. Lenssen, Mary H. Wiedenhoeft, Thomas C. Kaspar

Agronomy Conference Proceedings and Presentations

Iowa often has extreme weather events in the spring, a time when few fields in the state have a living cover, leading to nutrient leaching and erosion issues. These intense rain events also lead to excess soil moisture and runoff. While cover crops help address these issues and more, there has been little adoption of cover crops in Iowa (less than 1% of farmed acres). A commonly cited worry is that cover crops aren't worth the money that a farmer must invest. To offset costs, some farmers use their cover crops for haying or grazing, but a major constraint ...


Using Soil And Topographic Characteristics For Corn Seeding Rate Optimization In Iowa, Mark A. Licht, Andrew W. Lenssen, Roger W. Elmore Jan 2015

Using Soil And Topographic Characteristics For Corn Seeding Rate Optimization In Iowa, Mark A. Licht, Andrew W. Lenssen, Roger W. Elmore

Agronomy Conference Proceedings and Presentations

The capability to use variable seeding rates has increased dramatically in recent years. Meanwhile, farmers and agronomists frequently collect and analyze soil samples to determine nutrient needs for subsequent crops. The objective of this research was to use key soil and topographic parameters to optimize seeding rates to maximize grain yield. Treatments included five seeding rates (61,750; 74,100; 86,450; 98,800; and 111,150 seeds ha-1) in a randomized complete block design with four or five replications in three central Iowa fields from 2012 to 2014. Soil samples were analyzed for P, K, pH, SOM, CEC ...


Active Sensor Strategies For In-Season Application Of Urea In Corn, Daniel W. Barker, John E. Sawyer Jan 2014

Active Sensor Strategies For In-Season Application Of Urea In Corn, Daniel W. Barker, John E. Sawyer

Agronomy Conference Proceedings and Presentations

Addition of N fertilizer during the midvegetative corn (Zea Mays L.) stage is being used in Iowa to protect yield potential. The objective of this experiment was to compare pre-plant and in-season N application strategies, and evaluate N use efficiency and grain yield of sensor-based N rate application.


Evaluation Of Adapt-N In The Corn Belt, C. A. M. Laboski, J. J. Camberato, J. E. Sawyer Jan 2014

Evaluation Of Adapt-N In The Corn Belt, C. A. M. Laboski, J. J. Camberato, J. E. Sawyer

Agronomy Conference Proceedings and Presentations

Nitrogen is the plant nutrient required in the largest quantity, the most likely to be deficient, and the most impactful on corn yield as well as grower profit. Providing N to a corn crop in the right amount while minimizing loss is difficult because of complex biological and chemical reactions that result in the loss of N from the crop root zone via deep percolation to ground water, lateral flow, runoff and erosion to surface waters, and volatile losses to the atmosphere as ammonia, nitrogen gas, nitric oxide, nitrous oxide, etc. Increasing crop utilization of N and reducing loss of ...


Dryland Soil Carbon And Nitrogen After Thirty Years Of Tillage And Cropping Sequence, Upendra M. Sainju, Brett L. Allen, Thecan Caesar-Tonthat, Andrew W. Lenssen Jan 2014

Dryland Soil Carbon And Nitrogen After Thirty Years Of Tillage And Cropping Sequence, Upendra M. Sainju, Brett L. Allen, Thecan Caesar-Tonthat, Andrew W. Lenssen

Agronomy Conference Proceedings and Presentations

Little information is available about the long-term impact of tillage and cropping sequence on dryland soil C and N levels in the northern Great Plains. This study provided an opportunity to evaluate the effect of thirty years (1983-2013) of tillage and cropping sequence combination on dryland crop residue and soil organic (SOC) and inorganic C (SIC), soil total N (STN), NH4-N, and NO3-N contents at the 0- to 120-cm depth in eastern Montana. Treatments were no-till continuous spring wheat (NTCW), spring till continuous spring wheat (STCW), fall and spring till continuous spring wheat (FSTCW), fall and ...


Evaluation Of Optical Canopy Sensors For In-Season N Rate Management In Corn, Daniel W. Barker, John E. Sawyer Jan 2014

Evaluation Of Optical Canopy Sensors For In-Season N Rate Management In Corn, Daniel W. Barker, John E. Sawyer

Agronomy Conference Proceedings and Presentations

Optical canopy sensors are an emerging technology that can serve as a useful in-season N fertilizer management tool for corn (Zea mays L.) production. The sensors provide an estimate of plant biomass and N status at the time of sensing. These growth parameters can be used to make in-season N rate adjustments and variable rate N applications. Currently, a robust and accurate algorithm to determine the appropriate N rate based on canopy sensing is need in order to improve the effectiveness of active sensors in production fields. The objective of this study is to determine the ability of optical canopy ...


Optimizing Nitrogen Fertilizer Application In Corn Using Green Technology, Daniel W. Barker, John E. Sawyer Jan 2014

Optimizing Nitrogen Fertilizer Application In Corn Using Green Technology, Daniel W. Barker, John E. Sawyer

Agronomy Conference Proceedings and Presentations

The utilization of active canopy sensors in corn (Zea Mays L.) for in-season N fertilizer management has the potential to maintain optimal production and conserve fertilizer N resources. Canopy sensors can be considered a green technology in production agriculture by attempting equitable land stewardship and providing an economically viable N management practice. Robust and accurate algorithms to determine an appropriate N application rate based on canopy sensing is needed in order to effectively utilize sensors in Iowa production fields. The objective of this study was to develop N rate algorithms using active canopy sensors which can prescribe in-season N application ...


Corn Nitrogen Rate Response And Crop Yield In A Rye Cover Crop System, John E. Sawyer, Jose L. Pantoja, Daniel W. Barker Jan 2014

Corn Nitrogen Rate Response And Crop Yield In A Rye Cover Crop System, John E. Sawyer, Jose L. Pantoja, Daniel W. Barker

Agronomy Conference Proceedings and Presentations

Water quality impairment related to N loss from crop production fields continues to be a concern in Iowa, including meeting the USEPA nitrate-N drinking water standard and reducing N export to the Gulf of Mexico. Therefore, in-field production practices would be helpful to aid in reduction of nitrate leaching and movement to water systems. One practice identified in the science assessment for the Iowa Nutrient Reduction Strategy is use of a winter cereal rye (Secale cereal L.) cover crop, where a mean 31% (29% standard deviation) nitrate-N reduction would be expected, but with a 6% (22% standard deviation) corn yield ...