Illinois Crop Update – September 6, 2024
Russ Higgins – Commercial Agriculture Educator
Grundy County
Soil Conditions: Moderately Dry (soil is dry, plants may be browning or stressed, water bodies are low)
Another dry week. In travels across northeast Illinois we see both green corn and soy fields, and in others, plants that have browned, dropped leaves and are likely only weeks from harvest. We have had reports of hand shelled corn samples near 30% moisture. For areas that had heavier soils, received timely rains and had higher water holding capacity, the yields will be impressive. A visit to the Sandwich Fair this week judging corn entries demonstrated sizeable ears. If they are representative, it will be interesting to see final yields from these locations. Somewhat of a surprise, we are finding pockets of white mold in some soy. Even though the symptoms (dead plants) are easily visible now, the initial infection took place when the soy was in the R1 to R3 stage. Harvesting white mold infected soy last and then cleaning your combine can limit the spread of sclerotia, the overwintering structures of this disease, to other areas or fields. Tar spot continues it spread in corn, even in earlier fungicide treated fields.
Figure 1: White mold – Grundy County September 4, 2024
Figure 2: Sandwich Fair Corn entries Sept 2024
Talon Becker – Commercial Agriculture Specialist
McLean County
Soil Conditions: Near Normal
The corn and soybean crop in McLean County is looking good as many fields are nearing maturity. All corn fields surveyed were somewhere in the R5 (dent) stage with full ears, although a couple fields showed some bare ear tips. Low to moderate levels of stalk rot symptoms were visible in several fields surveyed. Minimal corn foliar disease was observed, although tar spot was found at low levels in a couple fields in the north and eastern parts of the county. The majority of soybean fields surveyed are in the later half of R6 (full seed), but a number of fields in the county are progressing into R7 (beginning maturity). Soil moisture conditions were good, with no standing water observed but moisture available at or just below the surface in fields surveyed.
Figure 3: Corn at R5 (dent) with milk line at approximately 30-40%
Figure 4: Soybean field at R7 (beginning maturity)
Reagan Tibbs – Commercial Agriculture Educator
Logan County
Soil Conditions: Near Normal
Many crops across Logan, Menard, and Sangamon counties are getting closer to harvest. Much of the earlier-planted corn and soybeans have turned color and are nearing R6 (physiological maturity). The later-planted crops still have some time to go, but they are not far behind. Parts of the area, mainly Sangamon County, received some good rainfall last week, adding some needed topsoil moisture. There should now be enough moisture to see us through to harvest.
Doug Gucker – Local Food Systems and Small Farms Educator
Dewitt, Macon, and Piatt County
Soil Conditions: Mildly Dry (soil is drier than normal, plant growth may have slowed)
Early planted corn has reached “black layer” with the milk line nearly reaching the tip of the kernel. Late planted corn is in late R4 stage. Early planted soybean leaves are turning yellow and nearly at R7 stage. Double cropped soybeans are reaching the R5 stage. Crops are maturing quickly. Some stinkbug pod feeding is being seen.
Figure 5: Three weeks difference in planting date is evident in the milk line of the two ears.
Figure 6: Late May planted corn in late R4 stage.
Figure 7: Double crop soybeans in R5 stage.
Dane Hunter – Commercial Agricultural Specialist
St. Clair County
Soil Conditions: Near Normal
Most corn is settling into dent (R5) at this point. I haven’t found any to black layer quite yet. First crop beans are around R6, but I haven’t seen any fields with yellowing leaves this far south yet.