Following the storms that came through the areas late last week, soils have plenty of moisture in the northern Vermilion County area. There was standing water visible in some small ponds in headlands, but these were few and far between. Crop health looked good, overall, but corn fields are starting to show some areas with late-season nitrogen stress with variable ear size and tip fill. Signs of what appears to be Physoderma stalk rot (visual identification only) were also present in a number of corn fields (https://cropprotectionnetwork.org/encyclopedia/physoderma-stalk-rot-of-corn). In fields surveyed, corn was at late R4 (dough) to early R5 (dent). Soybeans generally ranged from R4 (full pod) to R5 (beginning seed), with a few fields edging closer to R6 (full seed). Weed control was variable. Most corn fields I walked into were relatively clean, but soybean fields showed a range of weed control efficacy.

Crop growth remains much the same as last week. There were some pop-up showers on Monday, but these did not bring much in the way of total precipitation. Storms are in the forecast for tonight, so hopefully, there will be enough rainfall to replenish topsoil moisture. Much of the corn crop remains in the R4 to R5 stages, with the later planted corn in the R3 stage. Most of the soybeans in the area have fully developed pods, with some beginning to form seeds inside the pod.

Rain is in the forecast which would greatly benefit the soy crop in drier areas of Northeast Illinois, that crop is still at R5 or beginning seed. As we reach mid R5 we can expect the remobilization of nutrients from leaves and stems to start. While few reports of soy disease have been noted to date, a report of White Mold in Kane County was shared this week. Most corn fields visited are now at some stage of R5 or dent stage. In lighter soils lacking rain, significant firing is evident. As our crops near maturity many farmers have turned their attention to readying combines and other harvest equipment. While important, we can also find value in late season scouting visits. This week has been a very interesting in corn leaf diseases, Tar Spot continues to infect and spread within and across fields. This is the time to evaluate fungicide application efficacy or hybrids inherent or bred tolerance to Tar Spot and other diseases. In addition to Tar Spot, symptoms of Northern Corn Leaf Blight, Gray Leaf Spot and Southern Rust can be found in area corn fields. Visiting fields with disappointing weed control can also provide insight into management decisions in future years. Included is an image of Waterhemp treated with a tank mix of Enlist and Liberty that killed the apical meristem but not the plant. In visiting Dr. Aaron Hager, Weed Specialist at the University of Illinois, he shared the current message for Waterhemp control in soy. I had to chuckle (and could relate) at recommendation 7.
1) Use glufosinate with Enlist One instead of glyphosate. If we miss grass with the tankmix, we can always come back and clean it up with glyphosate. We do NOT want to miss the waterhemp with the first application.
2) Keep the water volume close to 20 gpa whenever possible.
3) Be sure to use the correct spray tips; these drift reduction nozzles are terrible for contact herbicides, such as glufosinate.
4) Spray small waterhemp. If the field average size is 4 inches, the reality is a field with plants ranging from 8 inches to ½ inch.
5) Keep the AMS at the label recommended rate. This is NOT the place to cut costs.
6) Glufosinate likes bright sunshine, high air temperatures, and high humidity. Applications made when one or more of these are missing often are somewhat compromised.
7) Spray glufosinate like you once sprayed Basagran (that one resonates only with those with at least a touch of gray hair).

Corn is in the dough to dent stage and generally looking good. Fields that have experienced hail after the ear formed are showing ear rots. Corn leaves tattered in every field across the area. No tar spot evident, yet.
Full season Soybean are in the R4-R5 stages and plant health is good. Double crop soybeans are in bloom with small pods forming at the lower nodes.

First crop soybeans range from beginning to set seed at R5 to some fields still in late R2 just starting to think about putting out pods. Double-crop soybeans are in R2, full of flowers.
Some corn is full dough stage and starting to firm up kernels but not quite to R5 yet. Later planted corn is still transitioning from the blister to the milk stage, R2-R3.

As we move into the later stages of grain fill, the corn and soybean crop in Douglas County is currently looking very healthy, overall. During my drive around the county, I saw very few soybean fields with drowned out areas. Soybean maturity in fields surveyed ranged from R5 (beginning seed) to R6 (full seed), with some more mature fields starting to show leaf senescence in the lower canopy. Most corn fields surveyed were in late R4 (dough) to early R5 (dent) and had full ears with minimal kernel abortion at ear tips. Soil moisture conditions were good, with drying in the top couple of inches but still plenty of plant-available moisture in the root zone.

Milder temperatures this week are great for pods and kernel fill. A few sprayers/airplanes in the air. Keep monitoring for insects and disease.

We have reached that time of year that we sit back and see how this crop is going to continue. We have several weeks for fungicide applications coming to an end. The aphids have disappeared, leaving behind some disappointing carnage in some corn fields. We will see how much damage was done come fall.

This week precipitation has been mixed in northeast Illinois, areas north of the Rte. 80 corridor have received multiple rainfall events while areas south have received limited to no precipitation. Soy continues to progress, reaching R5, beginning seed stage. Depending upon variety maturity and planting date, most corn fields visited were R3-R4 to R4-R5. An unwelcome discovery this week was significant Tar spot symptoms in several corn fields. The decision on using a fungicide treatment is difficult in later maturity stages, especially when we are near R5, the dent stage. A reminder that grain fill in the dent stage often extends to 30 days or more. However, with declining commodity prices farmers need to consider their ROI (return on investment) when considering a or additional fungicide applications. A tool available to aid in the decision making is the Corn Fungicide ROI Calculator from the Crop Protection Network. The purpose of the Corn Fungicide ROI Calculator is to share results from university uniform corn fungicide trials conducted in the United States and Canada and allow farmers and others in the agricultural industry to calculate the potential return on investment (ROI) for corn fungicide application across a variety of user-defined factors, which is based on research data included in this calculator. The two variables needed are expected corn yield and marketing price. The calculator can be accessed at https://cropprotectionnetwork.org/fungicide-roi-calculator

Crops across Logan, Menard, and Sangamon counties continue to grow and develop nicely, thanks to last week’s rain showers. Despite having high winds during some storms, there does not appear to be any wind damage to the crops. Many soybean fields are in the R4 stage, with some earlier planted fields beginning to develop seeds (R5). Much of the same can be said for the corn crop as well. Most fields are in the R4 dough stage, with some of the earlier planted fields beginning to dent (R5). The alfalfa across the area has grown back nicely as well, with last week’s rains and this week’s cooler temperatures helping. Most fields look to be in Stage 3 (early bud).