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Full-Text Articles in Life Sciences

Factors Affecting Timing And Intensity Of Calving Season Of Beef Cow-Calf Producers In The Midwest, Lee L. Schulz, Claire E. Andresen, Patrick J. Gunn Jan 2016

Factors Affecting Timing And Intensity Of Calving Season Of Beef Cow-Calf Producers In The Midwest, Lee L. Schulz, Claire E. Andresen, Patrick J. Gunn

Animal Industry Report

Despite demonstrated market incentives to adopt controlled calving seasons, many producers still have herds that calve somewhat broadly throughout the year. Primarydata, collected through a coordinated survey effort withUSDA’s National Agricultural Statistics Service, were usedto quantify factors that affect producers’ decisions regardingtiming and intensity of calving season. Ninety-seven, 50, 33,and 26% of farms calve in the spring (Mar, Apr, May),summer (Jun, Jul, Aug), fall (Sep, Oct, Nov), and winter(Dec, Jan, Feb), respectively. Twenty-two percent observeda calving season exclusively in the spring. Sixty-six percentof respondents indicated calving season was dictated byweather, 34% because of labor availability, and ...


Ratios And Benchmarks As Tools For Local Food Hub Decision-Making: A Comparative Case Study, Savanna May Lyons Jan 2016

Ratios And Benchmarks As Tools For Local Food Hub Decision-Making: A Comparative Case Study, Savanna May Lyons

Graduate Theses and Dissertations

Food hubs, or local food aggregation and distribution businesses, are triple-bottom-line firms that play an increasingly important role in connecting small and mid-sized farmers to wholesale and retail markets. This paper explores how food hubs can use their financial data to identify and address strengths and challenges in their operations. We propose a “dashboard” of key metrics and benchmarks for food hub managers, and apply it a comparative case study of four food hubs over three years of operations. We compare and contrast the liquidity, cash flow, efficiency, solvency and repayment capacity of the four cases, and analyze cross-cutting themes ...


New Models To Estimate Costs Of Us Farm Programs, Xiaohong Zhu Jan 2016

New Models To Estimate Costs Of Us Farm Programs, Xiaohong Zhu

Graduate Theses and Dissertations

In this study, I extended the stochastic model built by Babcock and Paulson (2012) to conduct a one-year cost projection for crop insurance in order to investigate its feasibility of being solely provided by private firms. Based on the 52 years’ yield data from 1961 to 2012, the risk consequences from insuring crop yield and revenue against losses are estimated to be far beyond what private insurers could bear on their own. However, reinsurance from the government provides an attractive incentive to insurance firms. Among the six insurance policies researched in this study, the minimum expected net underwriting gains to ...


Beef Species Symposium: Economic Considerations Related To U.S. Beef Herd Expansion, Glynn T. Tonsor, Lee L. Schulz Sep 2015

Beef Species Symposium: Economic Considerations Related To U.S. Beef Herd Expansion, Glynn T. Tonsor, Lee L. Schulz

Economics Publications

Significant attention perpetually surrounds possible changes in breeding herd inventories in the U.S. beef cattle industry. This article outlines economic considerations of U.S. herd expansion. Factors restricting expansion include land availability, increasing production efficiency, operator demographics, capital requirements, and commodity price volatility. Several offsetting factors support herd expansion including unprecedented cow–calf returns, ongoing global beef demand growth, and timing within the current cattle cycle. In addition to these industry-wide factors, several important variations in individual ranch considerations are outlined. The authors’ expectations on future herd dynamics are provided, highlighting broader implications for individual operations, industry leaders, and ...


Three Essays On Crop Yield, Crop Insurance And Climate Change, Lisha Li Jan 2015

Three Essays On Crop Yield, Crop Insurance And Climate Change, Lisha Li

Graduate Theses and Dissertations

The main subject of this dissertation includes the study of the impact of weather on crop yields and developing crop revenue insurance product. The dissertation limits its analysis to the state of Iowa because it's a critical corn production area in the United States. Chapter 2 introduced a dynamic linear model to measure weather-adjusted trends in Iowa corn yields. The weather factors consist of the amount of rainfall, temperature and a measurement of soil moisture. Results show a significant improved yield growth in the 1990s, controlling for the impact of weather. Results also indicate that the critical temperature varies ...


Three Essays On Modeling Biofuel Feedstock Supply, Wei Zhou Jan 2015

Three Essays On Modeling Biofuel Feedstock Supply, Wei Zhou

Graduate Theses and Dissertations

The general theme of this dissertation is modeling biofuel feedstock supply. All three essays focuses on different topics relating to the theme. The first essay considers supply of corn stover for a commercial production of a cellulosic ethanol plant. The economic trade-offs in determining the plant size under uncertain future corn stover yields and cellulosic ethanol prices are analyzed. We also estimate the impacts on optimal plant sizes under two payment schemes for corn stover procurement: plant pays for transportation cost and farmers pay for the transportation cost. My second essay analyzes the impact of ethanol mandates on corn prices ...


Three Studies On Applying Positive Mathematical Programming And Bayesian Analysis To Model Us Crop Supply, Michael Hudak Jan 2015

Three Studies On Applying Positive Mathematical Programming And Bayesian Analysis To Model Us Crop Supply, Michael Hudak

Graduate Theses and Dissertations

The purpose of this dissertation is to find a practical way of obtaining a reasonable crop supply model for the US using a limited dataset. This model can then be used for forecasting and impact modeling. The method that is central to this model is Positive Mathematical Programming (PMP) that allows for the calibration of a nonlinear programming model to mimic the observations. This method is improved by implementing Bayesian Analysis to allow for the model to consider a distribution for the supply elasticity.

Using this method a national model was formed using only five years of data. While there ...


Potential For Machinery: A Case Study Of Fruit And Vegetable Growers In Iowa, Nicholas Jon Pates, Georgeanne M. Artz Jan 2014

Potential For Machinery: A Case Study Of Fruit And Vegetable Growers In Iowa, Nicholas Jon Pates, Georgeanne M. Artz

Leopold Center Publications and Papers

This 28-page publication describes field machinery used on six Iowa fruit and vegetable operations. The case studies looked at how size, diversification, marketing strategies and production methods impacted decisions regarding machinery.


Delayed Planting, Prevented Planting And Replanting Crop Insurance Coverage, Steven D. Johnson, William M. Edwards May 2013

Delayed Planting, Prevented Planting And Replanting Crop Insurance Coverage, Steven D. Johnson, William M. Edwards

Integrated Crop Management News

The frequent rains that have soaked Iowa this year have left many corn and soybean fields unplanted or with flooded areas. Many producers are wondering what options they have under their multiple peril crop insurance (MPCI) policies.

In Iowa, the crop insurance “late planting period” for corn begins on June 1. Corn can still be planted after this date, but the insurance guarantee on those acres is reduced by 1 percent per day until the acres are planted. Corn acres planted after June 25 will receive insurance coverage equal to 60 percent of their original guarantee. Producers should keep accurate ...


Aflatoxin: Crop Insurance, Charles R. Hurburgh Jr., Chad E. Hart Sep 2012

Aflatoxin: Crop Insurance, Charles R. Hurburgh Jr., Chad E. Hart

Integrated Crop Management News

Aflatoxin is covered under multi-peril crop insurance. The settlement is done as a deducted percentage of actual yield depending on the aflatoxin level. Producers will receive the grain after settlement.


Insurance Coverage For Drought-Damaged Crops, William M. Edwards Jul 2012

Insurance Coverage For Drought-Damaged Crops, William M. Edwards

Integrated Crop Management News

Nearly 90 percent of the corn and soybean acres in Iowa are covered by multiple peril crop insurance. Drought damage is an insurable loss under these policies. Producers should consult with their crop insurance agents before harvesting or destroying any drought-damaged crops, however.


Farmland Rental Rates Show Continued Strength In 2012, William M. Edwards, Ann M. Johanns May 2012

Farmland Rental Rates Show Continued Strength In 2012, William M. Edwards, Ann M. Johanns

Integrated Crop Management News

Anyone who is involved with the rental market for Iowa farmland knows that rental rates have been pushed significantly higher by the favorable corn and soybean prices that farmers have enjoyed since 2010. This trend continued in 2012.


Early Planted Acres May Lose Replant Insurance, William M. Edwards Apr 2012

Early Planted Acres May Lose Replant Insurance, William M. Edwards

Integrated Crop Management News

Unusually warm and dry weather has allowed crop producers to start spring field work earlier than can be remembered by most people. Getting an early start on tillage and planting reduces the risk of getting behind schedule later if an extended period of rainy weather occurs, but it also has its risks. The Risk Management Agency (USDA) has some specific rules about early planted crops with regard to crop insurance coverage. For each insurable crop RMA has set an “early planting date.” The earliest planting dates allowed for counties in the state of Iowa are April 11 for corn and ...


Energy Use In Pig Production: An Examination Of Current Iowa Systems, Peter J. Lammers, M. Douglas Kenealy, James B. Kliebenstein, Jay D. Harmon, Matthew J. Helmers, Mark S. Honeyman Mar 2012

Energy Use In Pig Production: An Examination Of Current Iowa Systems, Peter J. Lammers, M. Douglas Kenealy, James B. Kliebenstein, Jay D. Harmon, Matthew J. Helmers, Mark S. Honeyman

Agricultural and Biosystems Engineering Publications

This paper compares energy use for different pig production systems in Iowa, a leader in US swine production. Pig production systems include not only the growth and performance of the pigs, but also the supporting infrastructure of pig production. This supporting infrastructure includes swine housing, facility management, feedstuff provision, swine diets, and manure management. Six different facility type × diet formulation × cropping sequence scenarios were modeled and compared. The baseline system examined produces 15,600 pigs annually using confinement facilities and a corn-soybean cropping sequence. Diet formulations for the baseline system were corn-soybean meal diets that included the synthetic AA L-lysine ...


Important Crop Insurance Dates, William M. Edwards Feb 2012

Important Crop Insurance Dates, William M. Edwards

Integrated Crop Management News

Even the best crop insurance plan is of little use if the right information is not collected and submitted on time. Likewise, if certain actions are not completed by the necessary date, producers may not receive full benefit from the risk protection that they have selected.


An Engineering-Economic Model For Analyzing Dairy Plug-Flow Anaerobic Digesters: Cost Structures And Policy Implications, Carol Rose Faulhaber, D. Raj Raman, Robert Burns Jan 2012

An Engineering-Economic Model For Analyzing Dairy Plug-Flow Anaerobic Digesters: Cost Structures And Policy Implications, Carol Rose Faulhaber, D. Raj Raman, Robert Burns

Agricultural and Biosystems Engineering Publications

Treating animal wastes through anaerobic digestion (AD) yields methane-rich biogas that can be used for power generation or heating, and a nutrient-rich digestate that can be land-applied as fertilizer. Furthermore, AD reduces odors from stored and land-applied manures. Despite these benefits, AD deployment rates in the U.S. are only 5% for dairy farms identified as suitable for AD by the U.S. Environmental Protection Agency. The objective of this study was to analyze the economic and technical limitations of farm-scale anaerobic digesters using a simple model permitting insight into the fundamental constraints on the technology. A model was developed ...


Flood Damaged Crops, Crop Insurance Payments And Lease Contracts, William M. Edwards Aug 2011

Flood Damaged Crops, Crop Insurance Payments And Lease Contracts, William M. Edwards

Integrated Crop Management News

Some Iowa corn and soybean producers are facing substantial if not complete crop losses due to flooding. In particular, many acres of crops in the Missouri River Valley have been under water for a month or more this year. Fortunately, nearly 90 percent of Iowa’s corn and soybean acres are protected by multiple peril crop insurance.


Dairy Goats, Mike Duffy, Jodi Calvert Oct 2010

Dairy Goats, Mike Duffy, Jodi Calvert

Extension and Outreach Publications

This fact sheet is a special project of the Leopold Center Policy Initiative and ISU Beginning Farmer Center. It is designed to give producers an idea about alternative enterprises that might work in their operation with regard to level of knowledge, capital and other factors.


Christmas Trees, Mike Duffy, Jodi Calvert Oct 2010

Christmas Trees, Mike Duffy, Jodi Calvert

Extension and Outreach Publications

This fact sheet is a special project of the Leopold Center Policy Initiative and ISU Beginning Farmer Center. It is designed to give producers an idea about alternative enterprises that might work in their operation with regard to level of knowledge, capital and other factors.


Nonsolar Energy Use And One-Hundred-Year Global Warming Potential Of Iowa Swine Feedstuffs And Feeding Strategies, Peter J. Lammers, M. Douglas Kenealy, James B. Kliebenstein, Jay D. Harmon, Matthew J. Helmers, Mark S. Honeyman Mar 2010

Nonsolar Energy Use And One-Hundred-Year Global Warming Potential Of Iowa Swine Feedstuffs And Feeding Strategies, Peter J. Lammers, M. Douglas Kenealy, James B. Kliebenstein, Jay D. Harmon, Matthew J. Helmers, Mark S. Honeyman

Agricultural and Biosystems Engineering Publications

Demand for nonsolar energy and concern about the implications of fossil fuel combustion have encouraged examination of energy use associated with agriculture. The United States is a global leader in pig production, and the United States swine industry is centered in Iowa. Feed is the largest individual input in pig production, but the energy consumption of the Iowa swine feed production chain has yet to be critically examined. This analysis examines nonsolar energy use and resulting 100-yr global warming potential (GWP) associated with the swine feed production chain, beginning with cultivation of crops and concluding with diet formulation. The nonsolar ...


Ag Decision Maker: Combine Ownership Or Custom Hire, William M. Edwards, H. Mark Hanna Nov 2009

Ag Decision Maker: Combine Ownership Or Custom Hire, William M. Edwards, H. Mark Hanna

Agriculture and Environment Extension Publications

Includes advantages and disadvantages of custom hiring and information on estimating costs; includes worksheets.


Comparison Of Construction Costs For Vegetated Treatment Systems In The Midwest, Bradley J. Bond, Robert T. Burns, Todd P. Trooien, Stephen H. Pohl, Christopher G. Henry, Lara B. Moody, Matthew J. Helmers, John Lawrence Jun 2009

Comparison Of Construction Costs For Vegetated Treatment Systems In The Midwest, Bradley J. Bond, Robert T. Burns, Todd P. Trooien, Stephen H. Pohl, Christopher G. Henry, Lara B. Moody, Matthew J. Helmers, John Lawrence

Agricultural and Biosystems Engineering Conference Proceedings and Presentations

Vegetated treatment systems (VTSs) provide an alternative to containment basin systems for beef feedlot runoff control. Beef producers in the Midwestern United States have shown an increasing interest in using VTSs as a perceived lower cost option to containment basin systems. This paper reports the actual construction costs associated with 21 VTSs (eight on permitted Concentrated Animal Feeding Operations (CAFOs) and 13 on non permitted Animal Feeding Operations (AFOs)) located within Iowa, Minnesota, South Dakota, and Nebraska. The VTS construction costs are reported on a per head basis in 2009 adjusted dollars for each system. Cost comparisons are presented between ...


Farmland Ownership And Tenure In Iowa 2007, Michael Duffy, Darnell Smith, Jennifer E. Reutzel Nov 2008

Farmland Ownership And Tenure In Iowa 2007, Michael Duffy, Darnell Smith, Jennifer E. Reutzel

Extension and Outreach Publications

This study focuses on forms of ownership and tenancy in Iowa in 2007.


Resource Conservation Practices: Consideration In Selecting No-Till, Mahdi Al-Kaisi, H. Mark Hanna, Michael D. Duffy Jul 2008

Resource Conservation Practices: Consideration In Selecting No-Till, Mahdi Al-Kaisi, H. Mark Hanna, Michael D. Duffy

Agriculture and Environment Extension Publications

Consider the advantages of a no-till system. This publication looks at weed control, residue management, equipment requirements, nutrient management and the results of yield and economic return studies.


Alternative Approaches For Sharing Machinery, Labor, And Other Resources Among Small- And Medium-Sized Agricultural Producers, Greg Colson Jan 2008

Alternative Approaches For Sharing Machinery, Labor, And Other Resources Among Small- And Medium-Sized Agricultural Producers, Greg Colson

Retrospective Theses and Dissertations

As the U.S. agriculture industry continues to become increasingly concentrated, the viability of small- and medium-sized farms faced with diminishing profit margins per unit of output hinges in part on their ability to expand operations. In this study, the solution to this problem of taking advantage of economies of scale through farm-level resource sharing arrangements is considered. Through a two phase data collection procedure, Midwestern farmer groups engaged in resource sharing arrangements were identified and investigated through a case study approach. Evidence from the case studies suggest that sharing of equipment and labor can yield not only financial benefits ...


Essays On Fall Fertilizer Application, Mira Nurmakhanova Jan 2008

Essays On Fall Fertilizer Application, Mira Nurmakhanova

Retrospective Theses and Dissertations

Increased use of nitrogen fertilizer in agricultural production has contributed to increased food production but also contributed to elevated concentration levels of nitrates in groundwater and surface water. High concentration levels of nitrates in drinking water supplied from groundwater and surface water have become a public concern because of their risks to human health.;One way to reduce nitrogen losses is to develop and apply technologies that enable farmers to more accurately match the amount and timing of fertilizer application to crop growth needs. It is best to apply nitrogen as close as possible to when crop needs it most ...


A Simulation Model Evaluating Costs Of Bovine Viral Diarrhea Virus (Bvdv) For A Typical U.S. Cow-Calf Producer And Benefits Of Multiple Test And Cull Strategies, Kelsey James Wittenberger Jan 2007

A Simulation Model Evaluating Costs Of Bovine Viral Diarrhea Virus (Bvdv) For A Typical U.S. Cow-Calf Producer And Benefits Of Multiple Test And Cull Strategies, Kelsey James Wittenberger

Retrospective Theses and Dissertations

Increasingly, veterinarian organizations in the United States recommend the control and eradication of Bovine Viral Diarrhea Virus (BVDV). Cow-calf producers comprise 35% of U.S. cattle; however, research on the effects of BVDV in these herds is limited. To gain a better understanding of the pathology of BVDV in cow-calf producers, a stochastic simulation model was developed in C++ to measure epidemiological and financial outcomes. Additional simulations were run to evaluate changes in producer profit for several test and cull strategies. Introducing a PI animal decreased profit by an average of {dollar}13,971 over 10 years. When a second ...


Three Essays On Contract Farming In China, Jianhua Zhu Jan 2007

Three Essays On Contract Farming In China, Jianhua Zhu

Retrospective Theses and Dissertations

Contract farming in China has grown rapidly over the past 10 years. The first part of this dissertation examines the evolution of contract farming, and explores the incentives to engage in contract farming, preferred contract provisions, and contract performance from the perspective of both Chinese farmers and contracting firms. Firm and household perceptions of contracting are assessed using data obtained from village and firm level surveys. Farmers identify price stability and market access as the key advantages to contracts, while firms consider improved product quality as the primary incentive to use contracts.;In Part II, the survey data are used ...


Three Essays On Risk And Uncertainty In Agriculture, Nicholas David Paulson Jan 2007

Three Essays On Risk And Uncertainty In Agriculture, Nicholas David Paulson

Retrospective Theses and Dissertations

The general theme of this dissertation is risk and uncertainty in agriculture, with each chapter addressing a specific topic related to agricultural risk and uncertainty. Chapter 2 examines the effects of production uncertainty on the types of contract structures used in specialty grain markets. A theoretical model of a contractual relationship between a monopsonistic processor and risk-neutral producers is presented. Two common contract structures, and their resulting effects on the sharing of production risk between buyer and seller, are compared. The spatial structure of yields and farm-level yield volatility are shown to have significant impacts on the processor's preferred ...


Incentives And Contract Design: A Case Study Of Farmland Lease Contracts In Us Agriculture , Keita Fukunaga Jan 2006

Incentives And Contract Design: A Case Study Of Farmland Lease Contracts In Us Agriculture , Keita Fukunaga

Retrospective Theses and Dissertations

In this dissertation, I have studied farmland lease contracts in U.S. agriculture. Using the data from the 1999 Agricultural Economics and Land Ownership Survey, I investigated the empirical determinants of contract design from the perspective of the principal-agent framework, which emphasizes the role of incentives. In the empirical analyses, I found evidence that incentives indeed play an important role in contract design. In chapter 2, I investigated the role of risk, transaction costs, and endogenous matching between the landlord and tenant in contract choice. I found that both risk and transaction costs affect contract choice. Furthermore, I found evidence ...