Integrated Crop Management News

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Nitrogen Loss?

December 18, 2015

Really, it just had to rain large amounts in December. Seems we can’t get any relief from worrying about excess rain and impacts on nitrogen (N). The questions have already begun – what about fall 2015 fertilizer and manure N applications?

A few things to consider.

It is quite hard to make an estimate of losses for such an extreme event and time of the year. Following are factors to consider that will affect loss potential, including if N was applied and if so what fertilizer product or manure source.

Hindsight is 20/20: What Can Be Learned from 2015

December 17, 2015
Scenario analysis of Yield Forecast Project at Ames for corn

As the saying goes, hindsight is 20/20; perfect vision. We often say “if we knew the weather, then we can provide the best recommendations.” Usually, we do not know the weather or we do not have the appropriate tools in place, so the questions remain unanswered. Now that we know the weather, the next important question is to determine what could have been done differently in 2015. This is an important part of understanding and evaluating production and environmental performance of our crop management decisions.

Yield Gap Analysis: What Limited Iowa Corn and Soybean Yields in 2015

December 17, 2015
Average yield gap between average potential and water-nitrogen limited yield

To evaluate how good corn and soybean yields were in 2015, farmers and agronomists compare their yields to those obtained in previous years. To answer why yields were higher or lower than past years, they develop hypotheses to explain factors that limited yields based on their own experiences, anecdotal evidence from neighbors, knowledge of crop growth and development, and weather patterns.

Wrap up and Validation of the Yield Forecast Project for 2015

December 10, 2015
Predicted vs. measured corn and soybean yields for forecast plots

During the 2015 growing season, a group of scientists from the Department of Agronomy ran a pilot project with the objective of forecasting end-of-season yields and in-season water and nitrogen dynamics (crop demand and soil supply).

Protect Your Investment by Eliminating Tillage and Keeping Residue

December 7, 2015
Field with residue removed

This fall, field observations with significant amounts of intensive tillage and residue removal provide an opportunity to rethink such practices by considering research proven practices such as no-tillage (NT) and strip-tillage (ST), which have demonstrated their effectiveness in many parts of the state and across the Midwest.

New Weed Identification Field Guide Provides Updated Weed and Herbicide Resistance Information

October 30, 2015
Weed Identification Field Guide

Iowa State University Extension and Outreach has released a new version of the Weed Identification Field Guide, first published in 2010, to assist producers and agronomists with accurately identifying weeds in Iowa corn and soybean fields. The Weed Identification Field Guide, 2nd Edition, includes additional weed species and updated information on herbicide resistance management. The guide is now available for purchase online from the Iowa State University Extension Store.

Record Number of SCN-Resistant Soybean Varieties Available, More with Peking Resistance

October 28, 2015
Number of SCN resistant varieties graph

Growing resistant soybean varieties is a great way to manage the soybean cyst nematode (SCN). And there are hundreds of varieties from which to pick. To make variety selection easier, ISU compiles a list of SCN-resistant soybean varieties annually, and the updated list has just been released. This year’s list contains a record-high number, with more varieties with Peking resistance than ever before.

Integrated Crop Management Conference Provides Latest Research and Technologies to Benefit Your Operation

October 27, 2015

Producers and ag business professionals reminded to register early

The annual Integrated Crop Management Conference will be held Dec. 2-3, 2015 at the Scheman Building on the Iowa State University campus. This year, the conference has added additional speakers to its program, providing topics and information on the latest in crop production and technology from around Iowa and the Midwest. Online registration is available at

Ag Chemical Dealer Update Meetings Provide Timely Crop Production Information

October 26, 2015

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 Nov. 24 and in Ames on Dec. 16.

These meetings are an excellent opportunity for ag input providers to meet with extension specialists to review current research, discuss new products and learn of new recommendations.