Illinois Crop Update- August 25, 2023
Russ Higgins – Extension Commercial Ag Educator
Grundy County
Soil Conditions: Mildly Dry (soil is drier than normal, plant growth may have slowed)
Recent high day and nighttime temperatures have local farmers and crops stressed. In my immediate area in northeast Illinois, the opportunity for “bonus fill” of kernels experienced last year appears very unlikely as the R6 (dent) corn hastens to maturity. Fields with greater water holding capacity are faring much better than lighter soils, but even those are showing some remobilization of nutrients from lower leaves in the canopy for the ear. Soy are nearing R6, having a green seed filling the pod at one of the top 4 nodes on the main stem with an open trifoliate.
Figure 1: Corn. Grundy County, August 24, 2023.
Figure 2: Remobilization from lower leaves. Grundy County, August 24, 2023.
Figure 3: R5.5 soybean. Grundy County, August 24, 2023.
Doug Gucker – Extension Local Food Systems and Small Farms Educator
Macon County
Soil Conditions: Mildly Dry (soil is drier than normal, plant growth may have slowed)
Here in my 3-county area (DeWitt, Macon & Piatt), soybeans for the most part are in Full Seed or R6 stage. Most all corn fields are in the Dent or R5 stage with the milk line clearly visible. Soybean vein necrosis virus (SVNV) is showing up in area fields should not affect yield and is caused by juvenile soybean thrips damage earlier in the season.
Figure 4: Soybean vein necrosis virus is present in a few fields in my area. Research shows that SVNV does not affect yield.
Figure 5: Most corn fields are in the Dent or R5 stage.
Figure 6: Soybean fields are in the Full Seed or R6 stage in my area.
Talon Becker – Extension Commercial Agriculture Educator
Vermilion County
Soil Conditions: Mildly Dry (soil is drier than normal, plant growth may have slowed)
This week, I visited fields in southwestern Vermilion County. Disease levels in both corn and soybean fields was minimal; I observed only a few isolated areas in soybean fields with foliar disease symptoms. Soybeans are mostly at R6 (full pod), but a few fields were still lagging behind, closer to R5. Corn fields I visited were in early to mid-R5 (dent). Ear fill was good in most fields I check, but I did find a couple fields that are struggling, with varying degrees of tipback as well as kernels aborted later in seed fill.
Figure 7: Soybeans and corn and Lincoln Marker on Champaign-Vermilion County line; recovered well following rough start to season (see June 23 post). Vermilion County, Aug. 25, 2023