This small area around the Kaskaskia River near Vandalia has been greatly affected by flooding. Both corn and beans in the floor plain are far behind, with large areas not able to recover. Large acres of soybeans were covered in mud and had corn residue stuck halfway up the plant. This has delayed the growth that would have normally been seen with the heat the area has received. The last rain on the 11th cleaned most of this up. It will be interesting to see how much if any is replanted. Double-crop beans are well under way.

Continued rain has been the story in south-central Illinois, with 0.63″ for the week ending 7/11/2026 and 1.83″ month-to-date for July. This has led to some prevented planting claims for soybeans in the area, including double-crop soybeans. This will provide an opportunity to close some combine ruts, manage residue, possibly clean a drainage ditch later in August. Have to figure out a good cover crop solution for the stubble, probably spring oats and crimson clover in August.

Early corn has reached R1-R2 growth stage, with good yield potential and fairly consistent pollination. Mid-season corn should tassel in the next week to 10 days. Replant corn is still at least a couple weeks away from pollination and has struggled to grow in wetter zones of fields. The ear leaf picture above illustrates how little disease pressure we see in early corn this year – no evidence of southern rust or tar spot yet and very little grey leaf spot (well below thresholds to trigger spraying). But recency bias from southern rust and tar spot in 2025 is leading many growers to make prophylactic/preventative fungicide applications to corn, even in the absence of disease. My suggestion would be to continue scouting and wait – we can still see a benefit from an application as late as R3 if disease shows up. And keep a close eye on the late-planted or replant crop, as the early corn could serve as incubation chambers for the late crop.

Early soybeans are R3-R4 and looking better now that rains have tapered some. Still some slow growth and general yellowing in low-lying areas that received too much water. Late season weed pressure could be a challenge this year, as high rainfall has allowed waterhemp to recover more effectively from post applications and has led to some degradation of residual herbicide. Some defoliation is present in the upper canopy but below threshold. And septoria brown spot is very prevalent in the lower canopy, as is commonly the case this time of year. I don’t see anything that would lead me to apply fungicide/insecticide to beans at this time.

Fungicides and disease scouting is our focus this week to ensure we are ahead of these yield robbing diseases. Corn and soybeans have had a great week with plenty of moisture in the soil and sunlight to keep growth and development active especially soybeans. They have turned from a visual yellow color to more of a dark green color across the region with the break in rainfall we have had this week. Aerial fungicide applications have kicked off with corn, and some ground fungicide applications have been sprayed in early planted soybeans. In the upcoming weeks fungicide applications will be in full flight.

This week farmland in the northeast region received additional precipitation and winds over the July 4th weekend. Rainfall totals reported ranged from 1+ inches to isolated fields that received 9+ inches. When sharing an update, the challenge is whether to report on the part of the field that has been unaffected (or even enhanced) by the rainfall, or the parts of the field that have been killed or damaged by ponding or saturated soils. Depending upon where you look, there are outstanding portions of fields, but if you evaluate the field as a whole and note the unevenness and drowned out areas the field overall rating diminishes. Soybean are at R2 or full flower, at this stage the plants begin a period of rapid dry matter and nutrient accumulation. This week shorter season or earlier planted corn hybrids have reached R1 or pollination and scouting for foliar leaf diseases has intensified. This job will soon be less pleasant when pollen shed increases. In fields scouted, I have yet to find symptoms of Tar Spot. I have noted black specks on corn leaves, but the Tar Spot stromata (lesions) cannot be brushed off. What I have found are either wind deposited dirt or possibly insect frass or excrement. If you can wipe off the black spot on a leaf it is not Tar Spot. Follow our weekly reports for updates on Gray Leaf Spot, Tar Spot, Southern Rust and other diseases found in both corn and soy across the state.

Taranis was showing areas in a double-crop soybean planting population on farm trial that had lower populations. Final stands ranged from 104,000 to 194,000. Overall, this ISA double-crop soybean (V4 growth stage) on-farm trial looked great; however, in some areas of the field, emergence could have been hindered by compaction. Corn had completed pollination and had entered the grain fill stage. Regular crop soybeans were at the R1 to R2 growth stage. No disease was found in both the corn and soybeans. There were minor signs of Japanese beetles in both corn and soybeans. Overall, it appeared to be dry at this location, but crops had not quite started to show signs of stress. It rained a bit during my field visit.

With the ample rainfall received over the past month, some fields in the area with low spots still have standing water and areas where the crop will not recover. It is advised to be diligent about scouting as fungicide application decisions are being made. As has been shared in other reports, the Crop Protection Network has useful resources that can aid in that decision making process. These include disease maps, the crop risk tool, and a fungicide ROI calculator: https://cropprotectionnetwork.org/

The corn in this field is exhibiting some potassium flashing on older leaves, which is a common occurrence in this field and tends not to have a negative effect on yield for this particular field. Little to no disease presence was noted, as only one northern corn leaf blight lesion was found.

The soybeans in this field (R2 growth stage) are exhibiting cupping on the upper canopy, and the cupping is widespread across the entire field. These are Enlist soybeans that were sprayed with Enlist + Liberty ten days prior to this field visit. There are other soybean fields within a roughly three-mile radius that are also exhibiting widespread cupping, along with fields that are not exhibiting any cupping. This could potentially be due to off-target dicamba movement.