Earlier this week, I had the opportunity to visit a field with probably the worst grape colaspis injury I have seen. Note the phosphorus deficiency symptoms on the lower leaves of many plants and the aggregated nature of the injured plants. Usually, we see this in fairly isolated areas of a field—often at the high points—and several nearby fields had this more limited injury. But in this particular case, much of the field was affected. When you see this kind of injury above ground, dig up the plant and look for larvae, which resemble tiny white grubs. Some plants in this field had as many as eight or nine larvae on them, and we found at least one pupa. These should cycle out into adulthood soon.

Crop growth is starting to vary across Logan County. Corn around the county looks very healthy, with many fields well above knee-high. Growth stages range between V4 and V6. Soybean growth is more varied. Some fields look healthy and are in the V4-V6 stage. However, some fields are lagging, with some in the V2 or V3 stage. With beneficial rains on 6/18 and more hot temperatures on the way, it will be interesting to see how these fields progress over the next week.

Both soybean and corn received a welcome rain on Monday, with local spots in Henry County receiving 1.5 inches and more in the forecast for Wednesday night—before a very hot and dry pattern sets in, with heat indexes forecasted to exceed 100 degrees. Corn is in the rapid growth stage, with most herbicide applications and sidedressing completed. Worked soybeans are outpacing those in no-till and minimum-till ground, and spraying is starting this week. Sprayers were rolling before the spotty thunderstorms arrived, with additional rain forecasted through midweek. Those unable to get into the field due to rainfall should have an opportunity later in the week as we shift to a hotter, drier summer pattern. These fields will need to be watched closely, as weeds will continue growing rapidly alongside the crop. Higher herbicide rates and different tank mixes may be necessary in these situations.

I was able to visit the Peoria Co. area this week to evaluate an Illinois Soybean Association sulfur plot. This is the earliest planted (April 12) and tallest (so far) ISA sulfur plot in the state. It had reached the R1 growth stage. Corn appeared to be at the V6–V7 growth stage. It is also interesting to note that pumpkins were once grown in this location and nearby. This week was hot with high humidity—you could practically hear the crops growing. Post-herbicide applications appeared to have taken place, and volunteer pumpkins were dying. Many soybeans showed herbicide speckling, which will likely disappear as the crop quickly grows. There was very little insect feeding, though some bacterial blight was present on the soybeans. This is a bacterial disease that favors cool, wet weather, so fungicides are ineffective.

We had 0.5 inches of rain last weekend, and coupled with 80-degree weather all week, the crop has really progressed. Corn is at V4 to V8 and beans are at V2 to V6, depending on planting date. The crop as a whole looks good, but we seem to find more uneven stands of corn every day. We think the top-end yield may be dwindling on the corn planted in late April to mid-May with each day we don’t get rain. The early April-planted corn looks the best.

Since last week’s update most of the region received 2”-5” of rain, so no planting has taken place.

Pictured here is a typical corn field planted on Memorial Day weekend, currently at V3, decent emergence during our relatively dry 3 week span, but some yellowing as a result of waterlogged soils.

First crop beans are still only partially planted, the typical field that did get in the ground is around VC-V2.

A typical wheat field in Marion county, largely golden, a few greens spots still remaining, grain is in dough stage.