Integrated Crop Management News

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Volunteer Corn Management

May 19, 2009

Volunteer corn is giving recently planted and yet-to-be planted corn and soybean fields a splash of green color. Manage volunteer corn early to avoid yield losses.

Degree Days - Brisk, but Basically OK

May 19, 2009
Image of base 50 degree F degree days in regions of Iowa from May 1 to May 17, 2009

by Rich Pope, Corn and Soybean Initiative

The week of May 10 was seasonally cold; all areas of Iowa fell behind long term average degree-day accumulations. Departures from normal were equivalent to 2.5 days of May growth in northwest Iowa to 3.5 days in southeast Iowa.

Map of accumulated degree days from May 1 through May 17, 2009.

May Crop Outlook

May 14, 2009
Table of planting progress (as of May 10th)

By Chad Hart, Department of Economics

With the May reports, USDA updated its estimates for 2008/09 and put out its first official estimates for 2009/10. On the corn side, ethanol and export demand are increased by 50 million bushels each for 2008. Both of these uses have experienced a rebound over the past few weeks.

Degree Days - Slow but Steady Progress in Planting

May 14, 2009
Image of base 50 degree F degree days in regions of Iowa from May 1 to May 10, 2009

by Rich Pope, Corn and Soybean Initiative

Iowa recorded temperatures close to season normals the week of May 4. Seasonal accumulated degree days are hovering near average in all crop reporting districts.

accumulated degree days as of May 10, 2009

May 11 Crop and Weather Report

May 12, 2009

Iowa State University Extension climatologist Elwynn Taylor, integrated pest management specialist Rich Pope, plant pathologist Daren Mueller and corn agronomist Roger Elmore join Doug Cooper for the weekly crop and weather report on May 11.

Taylor says weather patterns are starting to show a wet period moving into the Corn Belt and that could be very bad news for Illinois, Indiana and Ohio. La Niña continues to lose strength and should not be factor in the 2009 growing season.

Spring is Time to Check Alfalfa for Foliar Diseases

May 7, 2009
Image of characteristic lesion of alfalfa black stem

By XB Yang, Department of Plant Pathology

Early May is the time to check for alfalfa diseases. When spring has cool temperatures and frequent rains, the weather will promote the development of leaf diseases in some alfalfa fields. Knowing the occurrence of alfalfa diseases in early May helps make decisions about the first cutting. High levels of alfalfa foliar diseases such as spring back stem can cause early defoliation before you make the first cut, resulting in yield reduction.