Over the past weekend, a line of storms ripped across the area dumping unneeded rain, and in some areas, unneeded hail. While most of the media focussed on the urban damage in the Metro East areas of Madison and St. Clair counties, some of the rural areas suffered damage also. The picture above is what is left of what had been a beautiful field of newly pollinated wheat south of the Brownstown Agronomy Research Center. Fortunately the hail band from this storm cell was relatively narrow, but that is little consolation to those directly in it's path whose wheat crop is now 100 percent destroyed. Mother Nature can be pretty fickle sometimes.

We planted several corn research trials the week following Easter and have been waiting anxiously to see if any of them are going to emerge. Many producers in the region are doing likewise, and wondering if it is time to tear things up and replant. Fields that were ponded after receiving 3.5 inches of rain the weekend of April 14, as noted in my April 17 blog, are now finally drying out in the first picture above.

I went online and started calculating Modified Growing Degree Day accumulations, and find that Mother Nature seems to be confused this spring. How is it that average March temperatures can be greater than April temperatures? Based on data from the Vandalia weather station, modified GDD accumulations for the 17 days of March 15-31 totaled 260, while the accumulations for the 17 days of April 11-27 only totaled 147. Based upon those numbers, and allowing a little leeway for the couple of days the seed was actually under water, our corn planted on April 12 should be starting to emerge, and sure enough, it is as seen in the second picture above.

Take home message:  Don't write off corn planted in mid-April just yet. Good quality seed with today's fungicide/insecticide treatments may be more resilient than you realize!

Dr. Carl Bradley's article in last week's Bulletin indicated that wheat throughout Illinois should be monitored for the development of stripe rust. This disease prefers cool temperatures (<70 degrees), and can spread rapidly throughout the canopy and cause large yield losses under ideal environmental conditions.

The disease is heavily infesting some varieties in the breeding trials here at the Center, while other varieties show little or no evidence of infection at this time. Take home message:  Each field should be scouted, and management decisions based upon what is happening on a field-by-field basis. 

Over the next week, the majority of the wheat in the southern part of the state will complete the heading and pollination process. If you are out scouting fields (as you should be), you will pretty quickly notice that many of the flag leaves are discolored, ranging from yellow-to-purple (see first image above). This discoloration is symptomatic of a viral disease infection such as barley yellow dwarf virus. Dr. Carl Bradley has written an excellent article in this week's issue of The Bulletin outlining the various causal agents of viral diseases in wheat, and what you can (and can't) do to effectively control them. In that same issue, he has an article discussing application timing and product recommendations for control of fusarium head scab.

I have also received reports, and personally observed, that true armyworms (second image above) can now be found in some wheat fields. This does NOT necessarily indicate that fields need to be treated to control this insect pest. What it DOES mean is that it is time to get into fields and do some serious scouting. The economic thresholds for armyworms in wheat is six larvae per linear foot of row. Since the larvae are often hidden at the base of the plants and under residue and crop debris, it isn't much fun scouting. You have to get down on your hands and knees and look carefully.

If you do find armyworms at threshold levels in one field, don't automatically assume that they are at threshold levels in all fields. The opposite case holds true also: if you don't find them in a field, don't assume that all fields are clean. In past years I have scouted adjacent fields, separated only by a farm lane, and found high numbers in one field and almost nothing in the other.

Also keep in mind that armyworms are attacked by a number of natural enemies, particularly parasitic wasps, and that their populations can quickly crash naturally.

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It's hard to believe that last Friday morning soil conditions were so dry that some growers were considering putting a stop to planting. Three days, and 3+ inches of rain later, Mother Nature has put her own "stop" on planting progress and seedlings that haven't emerged need scuba gear! Hopefully a couple of sunny days along with breezy conditions will dry the soil enough to keep seeds from rotting in the ground.

With much of the wheat in the south either rapidly approaching or at pollination, the return to wetter conditions increases the concern about fusarium head blight (scab) potential. A useful decision aid tool can be found on the Wheat Fusarium Head Blight Prediction Center, hosted by Penn State University. The Risk Assessment Tool uses data from weather stations throughout the eastern U.S. to rank the probabilities for head scab potential.

The picture above is Dr. Carl Bradley's research trial studying fungicide efficacy. The sprinkler system will keep the field environment wet and humid, to help promote both foliar and head diseases. In addition, scab-infected milo seed has been spread to help insure that plenty of inocculum will be present to cause head scab. Only on a research center would one deliberately try to induce a disease to occur! 

It is only April 10th, and wheat development ranges from Feekes Growth Stage 9 (flag leaf emerged) here along the I-70 corridor, to approaching Feekes Growth Stage 10.5 (flowering) in the southern tip of the state. Development appears to be at least 2 - 3 weeks ahead of typical for this time of year.

Temperature predictions for tonight are for near freezing temperatures outside of the urban areas, so the potential for at least damage to the crop is very real. Data from Kansas indicates that temperatures of 28 - 30 degrees for two hours can cause moderate to severe damage to wheat when it is at boot stage to flowering. Hopefully it will not get that cold for that long.

As way of introduction, my name is Robert Bellm, and I am a University of Illinois Commercial Agriculture Crops Extension Educator working out of the University's Brownstown Agronomy Research Center.

Modern crop production practices are constantly evolving, and careers in crop production evolve right along with those practices. As a result of the recent reorganization of Extension, my career as a crop systems extension educator has evolved to include a greater involvement in applied field research, in addition to my more traditional extension outreach activities.

It is my intent to use this space to share information on current crop management issues, updates on potential pest outbreaks, reports on the latest field research, and general observations of crop conditions as the growing season progresses.