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Crop Advantage Series Provides Latest Crop Porduction Information Across Iowa, Brent A. Pringnitz Nov 2014

Crop Advantage Series Provides Latest Crop Porduction Information Across Iowa, Brent A. Pringnitz

Integrated Crop Management News

Iowa State University Extension and Outreach will offer the Crop Advantage Series to producers at 13 locations across Iowa during January. Crop Advantage Series provides the latest information to promote profitable decision-making for upcoming growing seasons. Each location features a full agenda of workshops that attendees can choose from to develop a personalized agenda. ISU Extension field agronomists will present program topics focusing on local needs and production issues.


Impact Of Liquid Swine Manure Application And Cover Crops On Groundwater Quality, Carl H. Pederson, Matthew J. Helmers, Rameshwar S. Kanwar, Antonio P. Mallarino Nov 2014

Impact Of Liquid Swine Manure Application And Cover Crops On Groundwater Quality, Carl H. Pederson, Matthew J. Helmers, Rameshwar S. Kanwar, Antonio P. Mallarino

Matthew J. Helmers

The primary objective of this project was to determine the impact of appropriate rates of swine manure applications to corn and soybeans based on nitrogen and phosphorus requirements of crops, soil phosphorus accumulation, and the potential of nitrate and phosphorus leaching to groundwater. Another purpose of this long-term experimental study was to develop and recommend appropriate manure and nutrient management practices to producers to minimize water contamination potential and enhance the use of swine manure as fertilizer. A third component of this study was to determine the potential effects of rye as a cover crop to reduce nitrate loss to ...


What Does It Take To Detect A Change In Soil Carbon Stock? A Regional Comparison Of Minimum Detectable Difference And Experiment Duration In The North Central United States, Magdalena Necpálová, Robert P. Anex Jr., Alexandra N. Kravchenko, Lori J. Abendroth, Stephen J. Del Grosso, Warren A. Dick, Matthew J. Helmers, Daryl E. Herzmann, Joseph G. Lauer, Emerson D. Nafziger, John E. Sawyer, Peter C. Scharf, Jeffrey S. Strock, Maria B. Villamil Nov 2014

What Does It Take To Detect A Change In Soil Carbon Stock? A Regional Comparison Of Minimum Detectable Difference And Experiment Duration In The North Central United States, Magdalena Necpálová, Robert P. Anex Jr., Alexandra N. Kravchenko, Lori J. Abendroth, Stephen J. Del Grosso, Warren A. Dick, Matthew J. Helmers, Daryl E. Herzmann, Joseph G. Lauer, Emerson D. Nafziger, John E. Sawyer, Peter C. Scharf, Jeffrey S. Strock, Maria B. Villamil

Agricultural and Biosystems Engineering Publications

Variability in soil organic carbon (SOC) results from natural and human processes interacting across time and space, and leads to large variation in the minimum difference in SOC that can be detected with a particular experimental design. Here we report a unique comparison of minimum detectable differences (MDDs) in SOC, and the estimated times required to observe those MDDs across the north central United States, calculated for the two most common SOC experiments: (1) a comparison between two treatments, e.g., moldboard plow (MP) and no-tillage (NT), using a randomized complete block design experiment; and (2) a comparison of changes ...


Hold Off On Tillage This Fall, Keep Soil Covered, Mahdi Al-Kaisi Oct 2014

Hold Off On Tillage This Fall, Keep Soil Covered, Mahdi Al-Kaisi

Integrated Crop Management News

This is the time of the year when tillage becomes the number one priority for some, whether they need it or not. The question to ask is, “Do I need to till this fall?” Given the economic and environmental challenges farmers are facing, the answer in most cases is no. With the end of the growing season here and harvest under way, now is a good time to start thinking about this decision. Take into consideration your site-specific condition and whether tillage makes economic and environmental sense given the input costs associated with tillage operations as well as the impact ...


Integrated Crop Management Conference Highlights Research And New Technologies, Alison E. Robertson, Brent A. Pringnitz Oct 2014

Integrated Crop Management Conference Highlights Research And New Technologies, Alison E. Robertson, Brent A. Pringnitz

Integrated Crop Management News

Iowa State University’s Integrated Crop Management conference will be held Dec. 3-4, 2014, at the Scheman Building on the ISU campus. Online registration is available at www.aep.iastate.edu/icm. “The latest information on crop production and protection technologies will be presented, giving producers and agribusiness professionals new information to use in their operations,” said Alison Robertson, crop plant pathologist and planning committee chair.


Ag Chemical Dealer Update Meetings Scheduled, Brent A. Pringnitz Oct 2014

Ag Chemical Dealer Update Meetings Scheduled, Brent A. Pringnitz

Integrated Crop Management News

Updates on the latest crop production products and recommendations are the featured topics at meetings sponsored by Iowa State University Extension and Outreach in Iowa City on November 25 and Ames, Iowa on December 10, 2014. These meetings are an excellent opportunity for agricultural input providers to meet with Extension specialists to review current research, discuss new products, and learn of new recommendations.


Understanding Engineering Students' Perceptions And Knowledge About Sustainable Development And Sustainability, Bhavna Sharma, Brian L. Steward, Say K. Ong, Fernando E. Miguez Oct 2014

Understanding Engineering Students' Perceptions And Knowledge About Sustainable Development And Sustainability, Bhavna Sharma, Brian L. Steward, Say K. Ong, Fernando E. Miguez

Agricultural and Biosystems Engineering Conference Proceedings and Presentations

The Sustainable Engineering and International Development course was first offered to engineering majors at the Iowa State University (ISU) in 2005. The course is focused on describing, discussing and comparing the key concepts of sustainability, sustainable development and sustainable engineering. In 2005, sustainability was not a major part of the engineering curricula and students had little to no knowledge about these concepts. Nine years later, sustainability has become an integral part of our daily lives. In this study, we wanted to understand student perceptions, knowledge, and understanding of sustainability, sustainable development and its implementation across various engineering systems. The assessment ...


Nitrogen Fertilization Rates For Corn Production, John E. Sawyer Oct 2014

Nitrogen Fertilization Rates For Corn Production, John E. Sawyer

Integrated Crop Management News

October 13, 2014 – There has been a large change in corn grain prices this fall. How might that affect recommended nitrogen (N) fertilizer or manure-N application rates, and planning for the 2015 crop? The answer depends on more than just the price of corn, but also the price of nitrogen. It is the ratio of these prices (price ratio, where the $/lb actual N is divided by the $/bu corn; example, $0.50/lb N and $3.50/bu corn is a 0.14 price ratio). Both prices are important and influence recommended N rates as the ratio reflects the ...


Fall Nitrogen Applications And Soil Temperature, John E. Sawyer Oct 2014

Fall Nitrogen Applications And Soil Temperature, John E. Sawyer

Integrated Crop Management News

If you are considering fall application of anhydrous ammonia to corn fields (the only nitrogen fertilizer recommended for fall application), remember to wait until soil temperatures cool to 50° F and continue to trend colder. The same guidance applies to manure with high ammonium N content, like liquid swine manure.


How Much Risk Of Frost Do You Have?, Mark A. Licht Sep 2014

How Much Risk Of Frost Do You Have?, Mark A. Licht

Integrated Crop Management News

The last USDA crop progress report indicates 72% of corn in or past the dent stage with 5% of the corn acres mature and soybean with 26% leaves turning color. Heat unit accumulation has been and continues to be slower than normal resulting in a crop that is not maturing as early as planned. With the 50% probability of a 28oF frost generally being mid- to late-October, there is some concern with a fall frost killing the crop before maturity is reached, especially for corn.


Revised Corn Yield Forecasts, Mark A. Licht Aug 2014

Revised Corn Yield Forecasts, Mark A. Licht

Integrated Crop Management News

With corn pollination complete and grain fill well underway, estimates of corn yield are being made across Iowa. On July 20, Corn Yield Predictions was written to provide an insight into corn yields forecasts based on the weather and management through pollination. This article is discussing a revised corn yield forecast now that grain fill is underway. The aforementioned article gives the background on the collaborative team, management/location assumptions and Hybrid-Maize model.


It's Palmer Time, Robert G. Hartzler Aug 2014

It's Palmer Time, Robert G. Hartzler

Integrated Crop Management News

The lack of reliable traits to distinguish Palmer amaranth and waterhemp during vegetative stages complicates efforts at stopping the spread of Palmer amaranth across the state. However, both plants should be in full reproductive mode at this time, greatly simplifying the identification of the two amaranths.


Is Dry Soybean Seed An Issue For 2012?, Mark A. Licht, Terry L. Basol, Andrew W. Lenssen Jul 2014

Is Dry Soybean Seed An Issue For 2012?, Mark A. Licht, Terry L. Basol, Andrew W. Lenssen

Andrew W. Lenssen

Areas of Iowa and other Corn Belt states were very dry during soybean harvest in 2011. Subsequently much of the soybean harvest occurred at lower than normal grain moisture levels, including soybeans grown for seed. We have heard reports from farmers, Extension and industry personnel that some fields were harvested with seed moisture as low as 7 percent. Handling seed with low moisture must be done very carefully to prevent damage to seed coats. This includes seed movement during harvest, seed cleaning, seed treatment and delivery to planters.


Alternatives For Drought-Damaged Soybeans—Bean Crop Or Forage, Stephen K. Barnhart, Andrew W. Lenssen Jul 2014

Alternatives For Drought-Damaged Soybeans—Bean Crop Or Forage, Stephen K. Barnhart, Andrew W. Lenssen

Andrew W. Lenssen

As people reflect on the reasons for the irregular development and poor soybean production in Iowa this year, the next important questions relate to evaluation of crops in individual fields and planning when and how to harvest them to the greatest economic advantage. This evaluation involves reviewing normal crop growth and development, assessing the condition of the crops in individual fields relative to normal and to think through several harvest scenarios. Will this field have a harvestable soybean crop? Are there concerns about the crops? What use or management alternatives do I have?


Recognizing Challenges To Iowa’S Annual Cropping Systems, David Wright, Andrew W. Lenssen Jul 2014

Recognizing Challenges To Iowa’S Annual Cropping Systems, David Wright, Andrew W. Lenssen

Andrew W. Lenssen

Iowa’s soybean and corn cropping systems are among the most productive in the world yet, producing consistently high yields remains uncertain. This publication discusses possible solutions to problems that limit soybean yield in Iowa.


Selecting Soybean Varieties, Joel L. Dejong, David Wright, Andrew W. Lenssen Jul 2014

Selecting Soybean Varieties, Joel L. Dejong, David Wright, Andrew W. Lenssen

Andrew W. Lenssen

Selecting the right combination of high yielding genetics and agronomic traits is the first management decision toward a successful soybean crop. This publication provides the reader with several tools that can be used to select high yielding soybean varieties best-suited to Iowa growing conditions.


Soybean Nutrient Needs, Clarke Mcgrath, David Wright, Antonio P. Mallarino, Andrew W. Lenssen Jul 2014

Soybean Nutrient Needs, Clarke Mcgrath, David Wright, Antonio P. Mallarino, Andrew W. Lenssen

Andrew W. Lenssen

Maintaining a fertile growing environment is a risk management strategy that produces higher yield and healthier plants that better manage stress. This publication outlines crop nutrient removal rates, foliar fertilization and the influence of soil fertility on plant health.


Staging Soybean Development, David Wright, Andrew W. Lenssen Jul 2014

Staging Soybean Development, David Wright, Andrew W. Lenssen

Andrew W. Lenssen

Accurate growth stage determination of soybean is essential to accurately apply pesticides and determine potential yield loss from environmental stress. This handy publication uses high quality images to enable the user to accurately stage soybean development.


Planting Soybean For High Yield In Iowa, Mark A. Licht, David Wright, Andrew W. Lenssen Jul 2014

Planting Soybean For High Yield In Iowa, Mark A. Licht, David Wright, Andrew W. Lenssen

Andrew W. Lenssen

Deciding when to plant soybean is an important management decision that greatly impacts yield. This publication discusses the potential yield increases from early planting and potential yield loss from delayed planting.


Inoculant Use On Soybean Seed, David Wright, Andrew W. Lenssen Jul 2014

Inoculant Use On Soybean Seed, David Wright, Andrew W. Lenssen

Andrew W. Lenssen

Inoculating soybeans with products containing the bacterium Bradyrhizobium japonicum is considered an inexpensive management practice to increase yield. However, yield gain from inoculants on soybean is inconsistent. This publication discusses the benefits and limitations of inoculant use on soybean.


Intermediate Row Width Can Increase Soybean Profits, David Wright, Andrew W. Lenssen, Virgil L. Schmitt Jul 2014

Intermediate Row Width Can Increase Soybean Profits, David Wright, Andrew W. Lenssen, Virgil L. Schmitt

Andrew W. Lenssen

Midwest research has documented that soybeans yield better when grown in 15 inch rows. However, there are limitations; some diseases of soybean can eliminate potential yield gains. This publication discusses several factors that should be considered when growing soybean in 15 inch row widths.


Soybean Response To Drought, Mark A. Licht, David Wright, Andrew W. Lenssen Jul 2014

Soybean Response To Drought, Mark A. Licht, David Wright, Andrew W. Lenssen

Andrew W. Lenssen

Drought is a serious but infrequent stressor affecting Iowa soybean production. This publication describes how soybean plant growth and development and nitrogen fixation respond to water deficit conditions. It also discusses simple management practices that have been shown to improve soil water holding capacity.


Humic And Fulvic Acids And Their Potential In Crop Production, David Wright, Andrew W. Lenssen Jul 2014

Humic And Fulvic Acids And Their Potential In Crop Production, David Wright, Andrew W. Lenssen

Andrew W. Lenssen

Humic and fulvic acids may have uses in Iowa’s large-scale production systems to improve seedling health and plant response to stress. This publication discusses the benefits and limitations of these intriguing organic compounds in soybean production.


Understanding Soybean Plant Population Recommendations For Iowa, Terry L. Basol, David Wright, Andrew W. Lenssen Jul 2014

Understanding Soybean Plant Population Recommendations For Iowa, Terry L. Basol, David Wright, Andrew W. Lenssen

Andrew W. Lenssen

Concerns over rapidly escalating seed prices have caused farmers, agronomists, and seed suppliers to revisit soybean planting rates. This publication discusses optimum soybean planting rates in Iowa and surrounding states. This is a must read for those who want to reduce their seed input costs


Influence Of Land Rolling On Soybean Production And Associated Weeds, Andrew W. Lenssen, Terry L. Basol, Joel L. Dejong, John D. Holmes, Mark A. Licht, Zachary A, Koopman, Micah B. Smidt, Joshua L. Sievers Jul 2014

Influence Of Land Rolling On Soybean Production And Associated Weeds, Andrew W. Lenssen, Terry L. Basol, Joel L. Dejong, John D. Holmes, Mark A. Licht, Zachary A, Koopman, Micah B. Smidt, Joshua L. Sievers

Andrew W. Lenssen

Land rolling soybean has become a common practice in some areas of northern Iowa. Land rolling pushes rocks and corn root balls down to the soil surface, improving combine harvest operations. However, land rolling field pea, barley, and summer fallow in eastern Montana essentially doubled density of several troublesome broadleaf weeds, including horseweed (also called marestail), kochia, Russian thistle, tumble mustard, prickly lettuce, and redroot pigweed. Iowa has different weed community and environments from Montana, and little is known how, or if, land rolling might influence weed community in Iowa. We conducted a replicated study on eleven Iowa farms on ...


July Spray Applications, Clarke Mcgrath, H. Mark Hanna Jul 2014

July Spray Applications, Clarke Mcgrath, H. Mark Hanna

Integrated Crop Management News

Applicators using ground sprayers for herbicide may be using higher speeds to catch up with weeds and cover more acres in a narrow time window. If so, they should consider the travel speed they've used to calculate appropriate nozzle size. If field speed increases by 25% (e.g., going from 12 to 15 mi/h), spray pressure for a given nozzle must increase by 56% (e.g., from 40 psi to 63 psi) to maintain output. A better choice to reduce smaller droplets and minimize drift would be to increase nozzle size.


Fungicide Thoughts For 2014 Season, Clarke Mcgrath, Daren S. Mueller, Alison E. Robertson Jul 2014

Fungicide Thoughts For 2014 Season, Clarke Mcgrath, Daren S. Mueller, Alison E. Robertson

Integrated Crop Management News

We will have a fair amount of corn tasseling shortly after the weekend — so fungicide application season is about here. In talking with farmers and retailers the last week or so, based on all the rainfall and wet soils this is shaping up to be a big year for fungicide applications, so just a few thoughts for guys "on the fence" and trying to decide whether to spray or not.


Controlling Large Weeds - Do You Feel Lucky?, Robert G. Hartzler Jul 2014

Controlling Large Weeds - Do You Feel Lucky?, Robert G. Hartzler

Integrated Crop Management News

The heavy rains across the state have made timely postemergence weed control difficult, even in fields treated with preemergence herbicides. This leads to questions as to what can be done to insure control of weeds larger than specified on herbicide labels. Keep in mind that if there was a way to improve the consistency of a herbicide on large weeds, the manufacturer probably would have included that practice on the label. This article will focus on managing large waterhemp in soybean, but many of the principles are the same with other weeds.


Assessing Crop Damage From Wind, Hail And Flooding, Mark A. Licht Jul 2014

Assessing Crop Damage From Wind, Hail And Flooding, Mark A. Licht

Integrated Crop Management News

Storms this past week have resulted in hail, wind and flooding damage across the state. Damage to both corn and soybean crops range from extensive defoliation to root lodging. In the coming week or two damaged crops should be assessed to determine how extensive the damage is.


Forage And Cover Crop Considerations For Delayed Planting And Flooded Sites, Stephen K. Barnhart, Brian J. Lang Jul 2014

Forage And Cover Crop Considerations For Delayed Planting And Flooded Sites, Stephen K. Barnhart, Brian J. Lang

Integrated Crop Management News

Extended periods of rainfall, flooding, hail, or all of the above have producers scrambling for replant or prevented planting options. Each choice has practical and economic implications, so should be approached with some thought. One consideration is the implication for crop insurance. Before changing crops or planting an 'emergency' forage crop, check with your crop insurance representative.