Browsing by Subject "Corn"
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Item A bio-economic assessment of the spatial dynamics of U.S. corn production and yields(2012-02) Beddow, Jason MichaelThis dissertation reports on an investigation into the effects of location on corn production and productivity. The landscape of crop production is dynamic--where crops are produced changes dramatically over time. The answers to important questions about the potential impacts of global climate change and whether agriculture will be able to meet the world's increasing need for food are affected by the moving footprint of production. However, most studies of agricultural productivity and the effects of global warming do not consider that agriculture moves, and that the concomitant changes in natural services have important effects. A full set of county-level census data on corn production and area in the United States have been digitized and assembled for the first time, and new methods have been applied to account for changing geopolitical boundaries. Concepts adapted from economic index number theory are used to show that some 15 to 20 percent of the change in U.S. corn output over the past 130 years has come about due to shifts in where corn is produced. A newly developed, long-run, corn-specific weather dataset is used with the county data to show that, because of changes in the location of production, U.S. corn is now grown in cooler climates than it was a century ago, possibly offsetting some of the potential impacts of climate change. Finally, methods from ecological modeling, spatial econometrics, and crop modeling are combined to create a corn yield model that is then used to develop a location- and season-specific crop suitability indicator that takes into account the intra-seasonal dynamics of weather and the complex relationships between weather and yields. It will be shown that the suitability metric developed in this study gives results that are both consistent and more interpretable than more traditional approaches.Item Corn production and environmental implications under varying nitrogen and management practices(2013-12) Maharjan, BijeshEconomic and environmental issues combined have increased the need for better understanding of the fate of nitrogen (N) applied to crop production systems. The objectives of this dissertation were to evaluate the effects of different N sources including conventional urea (CU), polymer-coated urea (PCU), stabilized urea with chemical inhibitors (IU), and anhydrous ammonia (AA) on N losses and yield. Besides N sources, their interaction with placement (deep- versus shallow-banded; broadcast/incorporation versus subsurface banding), tillage management (conventional tillage versus no tillage) and irrigation management (irrigated versus rain fed) were also studied. In the first experiment, split-applied CU increased yield and N uptake compared with preplant applied PCU or IU and decreased nitrate (NO3-) leaching compared with PCU in a sandy loam soil. Direct soil-to-atmosphere nitrous oxide (N2O) emissions were significantly less with IU or split-U than with PCU and there was a trend for greater emissions with split-U than with IU (P =0.08). Irrigation significantly increased NO3- leaching during the growing season, but had no effect on direct N2O emissions in the same experiment. Indirect emissions due to NO3- leaching were estimated to be 79-117% of direct emissions using the default value of EF5, thus signifying the potential importance of indirect emissions in evaluating management effects on N2O emissions. In the second experiment, no-till significantly increased N2O emissions in fertilized treatments in a dry year and decreased crop yield in the control treatment in a silt loam soil. There were no significant differences in N2O emissions, grain yield or NO3- leaching potential with AA placement depth. In the third experiment, mid-row banding (MRB) significantly increased N2O emissions compared to broadcast/incorporation (BI) for PCU and CU in silt loam soils. Nitrous oxide emissions were correlated to a greater extent with soil nitrite (NO2-) intensity than with nitrate (NO3-) intensity; N intensity being a measure of integrated N concentrations over time. Compared to BI, MRB reduced NH3 volatilization loss and the CU treatment had greater NH3 loss than PCU or IU had. All these experiments highlighted the significant roles that N and other management practices can play in mitigating N losses.Item Early Season Corn Development in a Kura Clover (Trifolium ambiguum Bieb.) Living Mulch(2017-04) Dobbratz, MichelleKura clover (Trifolium ambiguum Bieb.) perennial living mulch has many agronomic and ecological benefits, but corn produced in this system is often lower yielding than monocrop corn, and this yield loss is often preceded by delayed emergence and development. To prepare rows for corn production, kura clover is selectively killed in strips using mechanical or chemical means. We monitored kura clover health, soil moisture & temperature, corn emergence, corn development, and corn yield in four row preparation strategies: herbicide band kill (BK), shank tillage (ST), novel rotary zone tillage (RZT), and dual tillage (DT) which consisted of shank tillage followed by rotary zone tillage. Our primary objective was to compare novel RZT with the traditional strip tillage unit (ST). In 2015, corn grown in RZT plots emerged and developed faster than corn grown in ST plots, but this did not lead to a difference in grain or stover yield. In 2016, corn grown in RZT and DT plots emerged and developed faster than corn grown in ST and BK plots, and grain yield in 2016 was higher (P=0.05) in the RZT and DT (10.9 Mg ha-1 and 11.6 Mg ha-1) than in the ST and BK treatments (6.9 Mg ha-1 for both treatments). Kura clover biomass was not affected by treatment in either year. Based on these results, rotary zone tillage is a promising row preparation strategy in kura clover living mulch for corn production with minimal herbicide use.Item Economic and Environmental Costs and Benefits of Living Snow Fences: Safety, Mobility, and Transportation Authority Benefits, Farmer Costs, and Carbon Impacts(Minnesota Department of Transportation, 2012-02) Wyatt, Gary; Zamora, Diomy; Smith, David; Schroeder, Sierra; Paudel, Dinesh; Knight, Joe; Kilberg, Don; Current, Dean; Gullickson, Dan; Taff, SteveBlowing and drifting snow on Minnesota's roadways is a transportation efficiency and safety concern. Establishing standing corn rows and living snow fences improves driver visibility, road surface conditions, and has the potential to lower costs of road maintenance as well as accidents attributed to blowing and drifting snow. It also has the potential to sequester carbon and avoid the carbon emissions of snow removal operations. In recent years the Minnesota Department of Transportation (MnDOT) has paid farmers to leave standing corn rows to protect identified snow problem roadways. They have paid farmers $1.50 per bushel above market price. With increasing demand for corn to fuel the ethanol industry, paying $1.50 per bushel above market price may not be sufficient incentive for leaving standing corn rows. Also, with MnDOT’s memorandum of understanding with USDA to plant living snow fences through the Conservation Reserve Program (CRP), now is an opportune time to review MnDOT’s annual payment structure to farmers and prepare a new one. This project has: 1) developed a calculator to estimate payments for farmers that includes consideration of safety and snow removal cost savings; 2) estimated potential income from carbon payments; 3) worked closely with MnDOT engineers and plow operators, estimated the safety and snow removal costs and carbon emissions avoided by MnDOT through establishing living snow fences; and 4) evaluated farmers’ willingness to establish living snow fences and identified farmers/landowners’ constraints to adoption. Data is provided to MnDOT to assist staff in its decision making related to their Living Snow Fence Program.Item Economics of Owning and Operating Corn Drying and Storing Systems with Rising Energy Prices(Minnesota Agricultural Experiment Station, 1979) Jensen, Harald R.; Madsen, Jeffrey P.; Eidman, Vernon R.Item Effect of nitrogen on Bt gene expression in corn roots, resulting trait performance against corn rootworms (Diabrotica spp.), and transgenic hybrid performance(2013-01) Franz, Trisha MarieThis study examined the impact of nitrogen rates on the expression of corn rootworm (Diabrotica spp.) resistant traits in transgenic corn engineered to express one or more of Bt (Bacillus thuringiensis Berliner) Cry protein(s). The resulting protection against corn rootworm, and the comparative performance of hybrids containing zero, one or multiple (pyramided) corn rootworm traits were evaluated. Recommended nitrogen application rates have been suggested based on economics, but not for optimal expression of Bt Cry proteins. Specifically, this experiment explored the need to shift N rates to optimize Bt trait expression, corn rootworm protection provided by different traits, and a possible revision of nitrogen requirements for optimal yield with pyramided traits. The experiment featured a factorial treatment arrangement in a split-plot randomized complete block design with six nitrogen rates as the main plots and three hybrids differing in corn rootworm traits as the sub-plots. Corn roots were sampled at the beginning of and just after peak larval feeding and run through an Enzyme-linked Immunosorbant Assay (ELISA) to determine gene expression levels. Resulting root injury and adult emergence were measured to assess impacts on larval survival and damage. Root injury generally decreased with nitrogen rate in all hybrids while Bt gene expression, for Cry3Bb1, increased. Nitrogen rate did not affect expression of Cry34 Ab1/Cry35Ab1. Below-ground biomass was found to be highest in the Round-UpTM Ready hybrid at growth stage V6, along with nitrogen uptake. Nitrogen uptake was similar in VT TripleTM to the Round-Up Ready hybrid, which were both significantly higher than the Smart StaxTM hybrid. Yield for the Smart Stax hybrid did not plateau with the nitrogen rates applied at one site in this study, while the unprotected Round-Up Ready hybrid could not take advantage of the higher N rates. Implications of these results for growers in terms of adjusting nitrogen application rates in fields to obtain better gene expression, optimizing hybrid protection from corn rootworm traits, and reducing the risk of resistance are discussed.Item Effect of nitrogen on Bt gene expression in corn roots, resulting trait performance against corn rootworms (Diabrotica spp.), and transgenic hybrid performance(2013-01) Franz, Trisha MarieThis study examined the impact of nitrogen rates on the expression of corn rootworm (Diabrotica spp.) resistant traits in transgenic corn engineered to express one or more of Bt (Bacillus thuringiensis Berliner) Cry protein(s). The resulting protection against corn rootworm, and the comparative performance of hybrids containing zero, one or multiple (pyramided) corn rootworm traits were evaluated. Recommended nitrogen application rates have been suggested based on economics, but not for optimal expression of Bt Cry proteins. Specifically, this experiment explored the need to shift N rates to optimize Bt trait expression, corn rootworm protection provided by different traits, and a possible revision of nitrogen requirements for optimal yield with pyramided traits. The experiment featured a factorial treatment arrangement in a split-plot randomized complete block design with six nitrogen rates as the main plots and three hybrids differing in corn rootworm traits as the sub-plots. Corn roots were sampled at the beginning of and just after peak larval feeding and run through an Enzyme-linked Immunosorbant Assay (ELISA) to determine gene expression levels. Resulting root injury and adult emergence were measured to assess impacts on larval survival and damage. Root injury generally decreased with nitrogen rate in all hybrids while Bt gene expression, for Cry3Bb1, increased. Nitrogen rate did not affect expression of Cry34 Ab1/Cry35Ab1. Below-ground biomass was found to be highest in the Round-UpTM Ready hybrid at growth stage V6, along with nitrogen uptake. Nitrogen uptake was similar in VT TripleTM to the Round-Up Ready hybrid, which were both significantly higher than the Smart StaxTM hybrid. Yield for the Smart Stax hybrid did not plateau with the nitrogen rates applied at one site in this study, while the unprotected Round-Up Ready hybrid could not take advantage of the higher N rates. Implications of these results for growers in terms of adjusting nitrogen application rates in fields to obtain better gene expression, optimizing hybrid protection from corn rootworm traits, and reducing the risk of resistance are discussed.Item Influence Of Corn Crop Harvest Endpoint On Feedlot Performance, Beef Quality And Sensory Traits, And Return To Corn Land(2020-04) Johnson, TylerForty-nine Charolais x Red Angus steers (initial average BW = 536 kg) were fed individually in a Calan-Broadbent feeding system to evaluate performance and meat quality characteristics and interactions resulting from performance and crop yield when corn is harvested as either silage (SIL), earlage (EAR), high-moisture corn (HMC), or dry corn (DRC). Steers were randomly allocated to 1 of 4 dietary treatments where SIL, EAR, HMC, or DRC constituted 75% of diet DM. The remaining of SIL, EAR, HMC and DRC diets contained 11% haylage (0% for SIL), 10% modified wet corn distillers grains (MDGS), 4% liquid supplement with Rumensin (SUPP) and 11% DRC (SIL only). Gross return (gross $/hd) was determined as dollars remaining after subtracting non-corn crop expenses (cattle purchase, veterinary medicine, yardage, bedding and purchased feed ingredients) from gross cattle sale. Value of each corn crop endpoint was determined from corn grain worth ($/56 lb) and its relationship to corn grain content in SIL, EAR, and HMC crops. This value was compared to SIL, EAR, HMC worth determined by ANOVA (crop equivalent $/bu). Value of each corn crop endpoint was also determined by dividing gross return (gross $/hd) by hectares used to raise crop. The former method is used to determine corn crop endpoint worth for a feeder that purchases crops (owns no land) and the latter is used to determine corn crop endpoint worth for a feeder who owns corn land. Net return to corn hectares dedicated to cattle feeding during the last 18 years was 6.2 times greater than that realized through marketing corn through a local elevator. Cattle fed HMC had the lowest (P ≤ 0.05) DMI (dry matter intake). Cattle fed DRC had greater (P < 0.05) ADG (average daily gain) than cattle fed the other corn crops. Cattle fed HMC had greater ADG (P < 0.05) than those fed SIL. No difference between cattle fed DRC or HMC was observed for feed conversion but feeding either led to greater (P < 0.05) feed conversion than SIL or EAR. Final BW (body weight) and HCW (hot carcass weight) were greatest for DRC (P < 0.05), intermediate (P < 0.05) for HMC and lowest (P < 0.05) for EAR and SIL. There was a tendency (P = 0.08) for treatment effect on fat thickness wherein cattle fed DRC or HMC tended to have greater fat thickness than those fed SIL. No treatment differences were found for REA (ribeye area) or marbling. Sensory panel evaluation of loin steaks demonstrated that steaks from steers fed either SIL or EAR were juicier (P > 0.05) than those fed HMC and that bologna samples from steers fed HMC were toughest and least juicy. There was no effect observed for equivalent value of corn crop ($/bu). Harvesting corn as either SIL, EAR, HMC or DRC had no impact (P > 0.05) on crop worth (gross $ return/hectare). Despite performance differences, all harvest end points dedicated to cattle feeding result in greater gross return to corn land than marketing corn through local channels. This permits greater flexibility in corn harvest end point decisions for cattle feeders.Item Mitigation of Nitrate, Nitrous Oxide, and Ammonia Loss with Time And Source of Nitrogen Application in Corn(2022-08) Menegaz, SoniaThe large need of nitrogen (N) for crop production and the negative impacts of fertilizer on the environment result in a compelling need to identify new or advanced N management practices to reduce N losses while maintaining productivity and profitability. Nitrate (NO3) leaching, nitrous oxide (N2O) denitrification, and ammonia (NH3) volatilization are the most common pathways of N loss when synthetic N fertilizer is applied in agricultural lands. The objectives of this 7-year study (2014-2020) were to evaluate the use of traditional management (urea applied at pre-plant) and advanced [enhanced efficiency fertilizers and split applications] N management practices on i) N losses (NO3, N2O, and NH3); ii) corn yield and profitability; and iii) cropping system N balance including plant N removal and soil N status. The field experiment was conducted at the University of Minnesota Southwest Research and Outreach Center, near Lamberton MN. Four treatments were applied and replicated four times in a randomized complete block design: a pre-plant application of 202 kg N ha-1 of either urea (U) or polymer coated urea (PCU; ESN) (E) and 135 kg N ha-1 as urea with urease inhibitor (Agrotain) sidedressed at development stage V4-6 with 67 kg N ha-1 applied before planting as either urea (U/U+) or ESN (E/U+). Across the 7 years, the advanced management practice E/U+ increased corn grain yield (1 Mg ha-1 or 10%) and total N uptake (TNU, plant + grain N; 18 kg N ha-1) compared to the traditional management practice (U), while E and U/U+ had similar grain yields and TNU to the other treatments. Furthermore, while net economic returns (NER) were not statistically different between treatments, E/U+ generated numerically greater NER per hectare than U ($63), E ($52), and U/U+ ($46). Nitrate-N leaching (measured from 2015 to 2020) was highly influenced by weather. Excess precipitation, especially after fertilizer application, increased NO3-N loads, which was lower for E compared to the other treatments; however, flow-weighted NO3-N concentration was not different between treatments, with only a trend for lower NO3-N concentrations for E. Nitrous oxide emissions (measured from 2018 to 2020) also increased with excess precipitation, especially after fertilizer application. Split application treatments and U did not reduce N2O-N loss, but in wet years N2O-N loss was lower for E compared to the other treatments. This, however, was not observed in drier years or when precipitation was evenly distributed. Unlike NO3-N and N2O-N losses, ammonia volatilization (measured from 2019 to 2020), decreased as the result of excess precipitation that helped incorporate the fertilizer deeper into the soil. Overall, NH3-N loss was lower for E compared to other treatments. Integration of all the variables measured into a N balance calculation showed to be a poor approach to estimate N efficiency or impact on environmental quality because plant N uptake overshadow treatment influence on N loss measurements. Our findings indicate that pre-plant ESN can be considered a strategy to reduce N losses while maintaining crop yield. While split treatments increased corn yield, they did not reduce N losses, which contrasts the common assumption held by many that split applications are better for the environment. Nonetheless, the traditional management practice of pre-plant urea was the least efficient, producing lower crop yields and increasing N losses compared to pre-plant ESN in wet years. This demonstrates that there are N management practices that can improve production and environmental protection and their merit should be explored and refined further.Item Nitrogen Management for Corn Following Alfalfa: Field, Literature, and Geographic Analyses(2013-12) Yost, Matt AlanFirst- and second-year corn (Zea mays L.) following alfalfa (Medicago sativa L.) often require less supplemental N than corn grown continuously or following soybean [Glycine max (L.) Merr.]. The results of seven on-farm trials indicated that alfalfa can provide the entire N requirement of first-year corn no-till planted following alfalfa terminated in the fall. Eight other on-farm trials also indicated that first-year corn following alfalfa often does not require supplemental N (fertilizer or manure). The conclusion that first-year corn following alfalfa often requires no fertilizer N has been supported for decades, yet no research has identified site-specific conditions that cause first-year corn to respond to supplemental fertilizer N. The most widely used predictive test, the presidedress soil nitrate test (PSNT), had limited success in identifying response to N when trials from this study were combined with literature research; the test was 55% accurate across 94 site-years. An end-of-season test used to assess N supply to corn, the corn stalk nitrate test (CSNT), also was not successful in 11 trials at identifying when first-year corn would have required fertilizer N. An analysis of the literature was conducted to identify site-specific conditions that cause first-year corn following alfalfa to respond to N. Soil texture and alfalfa termination timing on medium-textured soils were significant covariates for identifying responsiveness to fertilizer N in first-year corn. First-year corn following alfalfa rarely required fertilizer N when alfalfa harvested for ¡Ý2 yr was fall-terminated on medium-textured soils; corn following alfalfa harvested 1 yr responded more frequently. The frequency of response to fertilizer N increased greatly when alfalfa was grown on coarse- or fine-textured soils and when alfalfa was terminated in the spring on medium-textured soils. For these conditions, combinations of alfalfa stand age and weather conditions explained much of the variation in whether a site would respond to N and the economically optimum N rate (EONR) at various price ratios (PRs) of fertilizer N/corn grain. The regression models developed to predict fertilizer N response appear robust, but require independent validation. Alfalfa also provides N to the second consecutive corn crop following alfalfa termination. Results from 28 on-farm trials in Minnesota and Iowa revealed that second-year corn required fertilizer N only 50% of the time. The same trend occurred when these trials were combined with 39 trials in the literature. The PSNT had higher accuracy for second-year corn (65%) than for first-year corn, but improvements in accuracy are still necessary in order for this test to be a reliable tool for growers. A geographic analysis revealed that growers in the U.S. Corn Belt region of the upper midwestern United States (North Dakota, South Dakota, Nebraska, Minnesota, Iowa, and Wisconsin) rotate alfalfa more frequently than in other parts of this region and that alfalfa phase length, soil texture, and year affect the type of crops grown for 2 yr following alfalfa termination. Supplemental files include data and references used for the literature analysis (Supplemental Table S4.1; Supplement S4.2), data used for analysis of second-year corn response to N (Supplemental Table S5.1), and alfalfa hectare estimates by state and year for the geographic analysis (Supplemental Table S6.1).Item A Quarterly Economic Model for Corn: A Simultaneous Approach to Cash and Futures Markets(Minnesota Agricultural Experiment Station, 1979) Subotnik, Abraham; Houck, James P.Item Rural School Agriculture. Bulletin no.2. Revised.(University of Minnesota, Department of Agriculture., 1907) University of Minnesota, Department of Agriculture; Bull, C.P.Item Source, Fall 2006(University of Minnesota Extension, 2006) University of Minnesota ExtensionItem Split application of sulfur and potassium and their leaching potential for corn grown on irrigated soils(2013-09) Bonde, Andria JansenIrrigated coarse textured soils have the potential to produce high yielding crops but are also likely to leach out fertilizer nutrients before they can be utilized. Few studies have considered split fertilizer applications of sulfur (S) and potassium (K) on coarse textured soils. Eight fertilizer studies, four S and four K, were conducted to assess how split applications of S and K fertilizers affect plant uptake, corn grain yield, and the leaching potential over the growing season. Each site had four at planting (AP) and four in-season (IS) fertilizer rates applied for a combination of 16 different fertilizer treatments. Various plant tissue, remote sensing readings, and soil samples were taken to assess nutrient availability and movement through the soil profile. Suction cup lysimeters were used in select treatments to monitor soil pore water concentrations. Single or split applications of S and K fertilizers did not increase grain yield. Significant differences among different AP and IS rates were found for early plant and ear leaf S and K concentrations, but these were unable to predict grain yield. Normalized difference vegetation index or SPAD chlorophyll readers did not prove to be indicators of final corn grain yield in either S or K studies. Plant NDVI data was able to predict biomass in K studies. Lysimeter data from S studies suggest increased S concentration towards the end of the growing season but provided no advantage of split application of S fertilizer to avoid S losses. Lysimeter data suggested early season K movement and in most sites and IS fertilizer application had the greatest effect on end of the growing season pore water K concentration. Because of potential early K movement, split applications may be advised for farmers growing corn on coarse textured soils to avoid K losses.Item Use of the 1992 ICC Public Use Waybill Sample to Analyze Corn Movements by Rail(1994-03) Fruin, Jerry; Halbach, DanThis report uses information from the 1992 ICC Public Use Waybill Sample to estimate the rail movements of corn throughout the U.S. during calendar year 1992. The data fields of the Waybill Sample are found on page 3. Report 1 contains the estimated number of carloads shipped from each origin BEA to each destination BEA as expanded from sample data. (BEA's are listed on pages 5 to 10 and partially shown on the map on page 11.) Also reported is the estimated number of bushels shipped in 1992 which is the expanded carloads times 3479.23 bushels per carload. Report 2 contains the same information but is summarized by destination BEA. Report 3 on page 46 is a summary of those records reported as origin BEA = 0 and destination BEA = 0 and accounts for 4,751 carloads or 16,529,822 bushels. Report 4 on page 47 is a summary of records with no origin BEA but a destination BEA. Report 5 is a summary of records with no destination BEA but an origin BEA.Item Web-Based Preventative Blowing and Drifting Snow Control Calculator Decision Tool(Minnesota Department of Transportation, 2015-05) Wyatt, Gary; Zamora, Diomy; Smith, David; Gullickson, Dan; Current, DeanBlowing and drifting snow on Minnesota's roadways are transportation efficiency and safety concerns. Establishing standing corn rows, living and structural snow fences or proper grading during road construction improves driver visibility and road surface conditions and has the potential to lower costs of road maintenance as well as crashes attributed to blowing and drifting snow. These snow control solutions can also provide environmental benefits including carbon sequestration and avoidance of carbon emissions of snow removal operations. In recent years, the Minnesota Department of Transportation (MnDOT) has paid farmers to establish snow control practices to protect identified snow problem roadways. Using public funds to pay landowners to establish land practices, which benefit the public and reduce MnDOT winter costs, needs to be justified. In 2012, our research team created a Microsoft Excel cost-benefit-payment calculator to estimate payments to farmers that included consideration of safety and snow removal cost savings to the public and the transportation agency. We worked closely with MnDOT engineers and plow operators to estimate the safety and snow removal costs. This project translated the Microsoft Excel tool to a web-based tool that can be used on laptops, smartphones and tablets. Beta testing has been done with transportation officials to improve the web tool. Outreach plans are being conducted to inform transportation agencies of this tool and the cost benefit analysis it offers.