Integrated Crop Management News

Links to these articles are strongly encouraged. Articles may be republished without further permission if published as written and if credit is given to the author, Integrated Crop Management News, and Iowa State University Extension and Outreach. If articles are used in any other manner, permission from the author is required.

Are Late-Season Soybean Aphid Treatments Worth It?

August 13, 2009
Graph of cumulative aphid days with different seed treatments

There is much evidence to show treating aphids when they exceed the economic threshold up to R5.5 will protect yield. But what happens if aphid populations are still increasing past seed set?

Managing White Mold at This Stage of Development

August 13, 2009

Despite some of the fungicides being classified as 'curative', there most likely will be little positive effect from any fungicide applied at this time because of the stage of the disease.

Degree Days - Average IS a Good Thing

August 11, 2009
Image of base 50 degree F degree days in regions of Iowa from May 1 to August 9, 2009

By Rich Pope, Department of Plant Pathology


A nearly average week of heat and some rain to boot! August could not have started better for Iowans, except for the band of hail and wind damage along the U.S. 20 / Iowa 175 corridor.  For the week, we only lost around 10 to 15 base-50F degree days to average across Iowa. Like they say, just what the doctor ordered (except for the hail!).


Statewide, corn development ranges from brown silk (R2) to dough stage (R3), and soybeans are busily filling pods (R4--R5).

Corn Hail Loss Chart and Things to Consider Following Hail

August 11, 2009
Graph of estimated percent yield reduction caused by hail damage

By Roger Elmore, Department of Agronomy


Hail storms again devastated portions of Iowa's corn crop on Aug. 9. Storms cut a 1 to 8 mile swath across north central Iowa. Producers in its path are asking, "How does hail after tasseling affect yield?" 


Getting to Know the Aphids in Corn

August 7, 2009
Image of a corn leaf aphid

There are at least two different species of aphids that can be found in corn this time of year, but the identification may not be critical to management.

Pages