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10,671 full-text articles. Page 6 of 203.

Alfalfa Winter Survival - A Complicated Subject, Brian J. Lang, Rebecca K. Vittetoe 2019 Iowa State University

Alfalfa Winter Survival - A Complicated Subject, Brian J. Lang, Rebecca K. Vittetoe

Integrated Crop Management News

How did alfalfa fields fair this past winter? This is a complicated subject since several factors play into alfalfa winter survival. These factors include fall soil moisture conditions, 4-inch soil temperature, and other stresses like stand age, soil fertility, and fall stubble.


Flooding And Stored Grain, Charles R. Hurburgh 2019 Iowa State University

Flooding And Stored Grain, Charles R. Hurburgh

Integrated Crop Management News

The rapid snowmelt in Spring 2019 has caused instances of stored grain being covered with floodwater. By current Food and Drug Adminstration (FDA) policy, grain inundated by uncontrolled river or stream water is considered adulterated and must be destroyed. The situation in 2019 is one of river water flooding rather than of rain-driven pooled water in low ground, for which there are salvage options. As shown by the example of the inundated Omaha sewage treatment plant, river-based floodwaters can bring in many hazards and rapid spoilage.


Equipment Considerations For Anhydrous Ammonia Application, Mark Hanna, John E. Sawyer 2019 Iowa State University

Equipment Considerations For Anhydrous Ammonia Application, Mark Hanna, John E. Sawyer

Integrated Crop Management News

Because of limited fall 2018 anhydrous ammonia fertilizer application, fertilizer infrastructure including transportation, distribution, and application may be stressed this spring. A review of application equipment considerations can help ensure that your nitrogen fertilizer is properly and safely applied. This article focuses on anhydrous ammonia equipment.


Spring Burndown Treatments For Winter Annual Weeds, Meaghan J. B. Anderson, Robert G. Hartzler 2019 Iowa State University

Spring Burndown Treatments For Winter Annual Weeds, Meaghan J. B. Anderson, Robert G. Hartzler

Integrated Crop Management News

With the short timeframe for fieldwork this spring prior to planting, early weed management may fall to the bottom of the priority list for many. For those who have persistent issues with winter annuals (field pennycress, horseweed/marestail) in no-till, an early burndown treatment may be worth the extra effort this spring. Winter annuals resume growth soon after the arrival of warm temperatures, so as soon as fields are fit the weeds will be susceptible to spray.


Effects Of Unharvested, Shattered, Or Hailed-Out Soybean Fields On Nutrient Supply For Corn, John E. Sawyer 2019 Iowa State University

Effects Of Unharvested, Shattered, Or Hailed-Out Soybean Fields On Nutrient Supply For Corn, John E. Sawyer

Integrated Crop Management News

Flooded fields and wet soil conditions in the fall 2018 meant some soybean fields were not, or are not going to be harvested. Also, some fields occasionally experienced significant shattering or a hailstorm in the fall where soybean seed is knocked from the plants and thus not harvested. When the grain is not harvested, nitrogen (N), phosphorus (P), and potassium (K) nutrients returned to the soil in the soybean grain can be accounted for when planning nutrient applications for the next crop. Other nutrients will also be returned, but most are not a fertilization need in Iowa soils. An estimate ...


Development Of A Nitrogen Recommendation Tool For Corn Considering Static And Dynamic Variables, Laila A. Puntel, Agustin Pagani, Sotirios V. Archontoulis 2019 University of Nebraska - Lincoln

Development Of A Nitrogen Recommendation Tool For Corn Considering Static And Dynamic Variables, Laila A. Puntel, Agustin Pagani, Sotirios V. Archontoulis

Agronomy & Horticulture -- Faculty Publications

Many soil and weather variables can affect the economical optimum nitrogen (N) rate (EONR) for maize. We classified 54 potential factors as dynamic (change rapidly over time, e.g. soil water) and static (change slowly over time, e.g. soil organic matter) and explored their relative importance on EONR and yield prediction by analyzing a dataset with 51 N trials from Central-West region of Argentina. Across trials, the average EONR was 113 ± 83 kg N ha−1 and the average optimum yield was 12.3 ± 2.2 Mg ha−1, which is roughly 50% higher than the current N rates ...


Understanding Anhydrous Ammonia Application In Soil, John E. Sawyer 2019 Iowa State University

Understanding Anhydrous Ammonia Application In Soil, John E. Sawyer

Integrated Crop Management News

What happens when anhydrous ammonia is injected into soil?

Several physical and chemical reactions take place following anhydrous ammonia injection: dissolution in water, reaction with soil organic matter and clay, and attachment of ammonium ions on the soil cation exchange complex. These reactions all tend to limit the movement of ammonia, with water having the greatest initial effect. The highest concentration of ammonia is at/near the point of injection, with a tapering of the concentration toward the outer edge of the retention zone. Usually the greatest ammonia concentration is within the first inch or two of the injection point ...


Anhydrous Ammonia Application -- Spring 2019, John E. Sawyer 2019 Iowa State University

Anhydrous Ammonia Application -- Spring 2019, John E. Sawyer

Integrated Crop Management News

It was a late harvest in fall 2018. Soils were wet and frozen when it was time to apply anhydrous ammonia. Those situations resulted in much less than normal anhydrous ammonia application last fall. Therefore, considerable anhydrous ammonia needs to be applied this spring. There is only so much capacity to switch from one nitrogen (N) fertilizer product to another. In Iowa, historically the two largest N fertilizers are anhydrous ammonia (largest) and urea-ammonium nitrate (UAN) solution, with granulated urea a distant third.


Spring Planting And Wet Soil Management, Mahdi Al-Kaisi 2019 Iowa State University

Spring Planting And Wet Soil Management, Mahdi Al-Kaisi

Integrated Crop Management News

The above-average snowfall and potential for significant rain events this spring could present challenges during the upcoming planting season. These conditions, on top of excessive soil moisture last fall that may have led to compaction and soil damage during and following harvest, have farmers concerned about completing spring tillage, fertilizer and planting operations in a timely manner. However, it is important to determine soil moisture conditions before getting in the field this spring in order to avoid additional damage to the soil and hurting future production.


Conducting On-Farm Trials, Mark Licht, Mike Witt 2019 Iowa State University

Conducting On-Farm Trials, Mark Licht, Mike Witt

Integrated Crop Management News

On-farm trials are an easy way for farmers to learn how practices, products and equipment will work in their cropping systems. The concept of on-farm trials has been around for decades, with farmers placing rows or strips of different practices within their fields for comparison. On-farm trials are easier to conduct now with assistance from formalized on-farm trial programs and the use of GPS and precision technologies.


Consider Frost Seeding Or Interseeding Pastures This Spring, Stephen K. Barnhart 2019 Iowa State University

Consider Frost Seeding Or Interseeding Pastures This Spring, Stephen K. Barnhart

Integrated Crop Management News

Producers wanting to add to or improve the forage species in their existing pastures should typically consider using either the frost seeding method in February and early March, or interseeding later in the spring months. This has been an unusual end to the winter, so as soon as the snow melts, frost seeding can begin.


Using Drones For Precision Agriculture, Jiyul Chang, Madhav P. Nepal 2019 South Dakota State University

Using Drones For Precision Agriculture, Jiyul Chang, Madhav P. Nepal

iLEARN Teaching Resources

In this teaching module, students will learn what Precision Agriculture is and how to apply drone into Precision Agriculture practices. To use data (images) taken by drone, students will learn the basic theory of Remote Sensing. Using images, students learn how to make NDVI (Normalized Difference Vegetation Index) maps and how to apply drone (remote sensing technique) in agriculture.


Improving The Distribution And Use Of Biogas By Conversion To Methanol, Zachary Christman 2019 University of Nebraska - Lincoln

Improving The Distribution And Use Of Biogas By Conversion To Methanol, Zachary Christman

Theses, Dissertations, and Student Research in Agronomy and Horticulture

In this technology review, the process of turning an average biogas into methanol will be presented. The purpose is to find a better method of transporting the energy contained within biogas so that it may be used in industry as a value added product. The first step is removal of hydrogen sulfide, a corrosive chemical that can breakdown mechanical parts. The second step is carbon capture and conversion of the biogas into hydrogen. The final step is the hydrogenation of carbon dioxide into methanol using a copper catalyst and an alcohol co-catalyst.


Medicago Sativa Has Reduced Biomass And Nodulation When Grown With Soil Microbiomes Conditioned To High Phosphorus Inputs, Laura M. Kaminsky, Grant L. Thompson, Ryan V. Trexler, Terrence H. Bell, Jenny Kao-Kniffin 2019 Cornell University

Medicago Sativa Has Reduced Biomass And Nodulation When Grown With Soil Microbiomes Conditioned To High Phosphorus Inputs, Laura M. Kaminsky, Grant L. Thompson, Ryan V. Trexler, Terrence H. Bell, Jenny Kao-Kniffin

Grant Thompson

Agricultural over-fertilization may adversely impact plant−microbial interactions affecting crop yield. It is unclear if soil microbiomes respond quickly to changes in fertilizer inputs once conditioned to specific nutrient regimes. We conducted a growth chamber study assessing the compositional and functional resilience of root-associated microbiomes of Medicago sativa to nutrient regime changes, and consequences for plant growth. Plants were grown with a common starting soil microbiome under four nutrient treatments: control (no fertilizer), organic phosphorus (compost added), low inorganic P (low triple superphosphate, TSP) and high inorganic P (high TSP). After several conditioning generations, in which microbiomes from rhizospheres of ...


A Theoretical Model Of Underground Dipole Antennas For Communications In Internet Of Underground Things, Abdul Salam, Mehmet C. Vuran, Xin Dong, Christos Argyropoulos, Suat Irmak 2019 Purdue University

A Theoretical Model Of Underground Dipole Antennas For Communications In Internet Of Underground Things, Abdul Salam, Mehmet C. Vuran, Xin Dong, Christos Argyropoulos, Suat Irmak

Faculty Publications

The realization of Internet of Underground Things (IOUT) relies on the establishment of reliable communication links, where the antenna becomes a major design component due to the significant impacts of soil. In this paper, a theoretical model is developed to capture the impacts of change of soil moisture on the return loss, resonant frequency, and bandwidth of a buried dipole antenna. Experiments are conducted in silty clay loam, sandy, and silt loam soil, to characterize the effects of soil, in an indoor testbed and field testbeds. It is shown that at subsurface burial depths (0.1-0.4m), change in soil ...


Managing Wet And Cold Soils, Mahdi Al-Kaisi 2019 Iowa State University

Managing Wet And Cold Soils, Mahdi Al-Kaisi

Integrated Crop Management News

The amount of snow we received and potential spring rain events can be challenging to an early start to the growing season. Approaching field operations for N applications, tillage, weed control, etc. need to be weighed against potential soil compaction and successful seed germination. Two of the greatest concerns during spring is excess soil moisture and cold soil temperature and their impacts on seed germination, especially in areas with poorly drained soils as in northern and central Iowa. Areas with poorly drained soils can be managed with less tillage to ensure suitable soil conditions for plant growth. Tillage systems that ...


Toxin Levels In 2018 Corn, Charles R. Hurburgh, Erin Bowers, Alison Robertson, Jason Ross 2019 Iowa State University

Toxin Levels In 2018 Corn, Charles R. Hurburgh, Erin Bowers, Alison Robertson, Jason Ross

Integrated Crop Management News

The two bu/acre Iowa corn yield reduction (from the previous 2018 report) shown in the February 9 crop report demonstrated the impact of late-season wet weather. Corn quality and potential food safety issues are also determined late in the growing season. According to data recently completed by the Iowa Department of Agriculture and Land Stewardship (IDALS), levels of the mycotoxins deoxynivalenol (also known as vomitoxin) and zearalenone are elevated in this year’s Iowa corn crop. Vomitoxin primarily affects digestion in swine, while zearalenone has negative effects on reproduction in most monogastric animals. Dogs, cats, and gilts are most ...


Will The Insects Survive This Winter?, Erin W. Hodgson 2019 Iowa State University

Will The Insects Survive This Winter?, Erin W. Hodgson

Integrated Crop Management News

It is not easy for insects to survive Iowa winters. Some literally can’t - they freeze to death (corn earworm, black cutworm) or migrate to warmer climates (potato leafhopper). Insects are unlike mammals and birds because they must generate their own heat (called ectotherms). Insects die when they are exposed to temperatures below the melting point of their body fluids, termed the lower lethal temperature. Over time, insects have developed several strategies to survive cold temperatures and none of them involve wearing fleece. Many insects have adapted to cold temperatures by entering diapause, which is like hibernation. Diapause is a ...


Evaluation Of Foliar Fungicides On Soybeans In 2018, Daren S. Mueller, Yuba Kandel, Stith Wiggs 2019 Iowa State University

Evaluation Of Foliar Fungicides On Soybeans In 2018, Daren S. Mueller, Yuba Kandel, Stith Wiggs

Integrated Crop Management News

Soybean foliar fungicides were evaluated for foliar disease management and yield response across seven Iowa State University research and demonstration farms in 2018. These included the Northwest Research and Demonstration Farm(Sutherland), Northern Research and Demonstration Farm (Kanawha), Northeast Research and Demonstration Farm(Nashua), Central Iowa Research Farms (Ames), Armstrong Memorial Research and Demonstration Farm (Lewis), McNay Memorial Research and Demonstration Farm (Chariton), and Southeast Research and Demonstration Farm(Crawfordsville).


Summary Of Foliar Fungicide Applications On Corn In Iowa In 2018, Alison E. Robertson 2019 Iowa State University

Summary Of Foliar Fungicide Applications On Corn In Iowa In 2018, Alison E. Robertson

Integrated Crop Management News

In 2018, we tested various foliar fungicides on corn at six locations in Iowa: ISU Northwest Research and Demonstration Farm (NWRF), Sutherland; Northeast Research and Demonstration Farm (NERF), Nashua; Northern Research and Demonstration Farm (NRF), Kanawha; Southwest Research and Demonstration Farm (SWRF), Lewis; Southeast Research and Demonstration Farm (SERF), Crawfordsville; and the Ag engineering and Agronomy Farm near Boone.


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