Another week with precipitation, in many areas ground sprayers have been unable to operate since June 7th. Many fields that are inherently poorly drained are ponded and both corn and soy are suffering. Farmers are facing the challenge of post applications of herbicide for corn and soy, and in some cases nitrogen for the corn crop. Warmer and dryer weather is desperately needed for the crops in the area. Most soy in the area not stressed by saturated soil has reached R2 (full flower), corn has reached V11. Waterhemp has reached 18 to 24 inches in untreated fields. Area alfalfa fields are flowering and Japanese Beetle have emerged in Northeast Illinois.

When I left Illinois for a brief vacation the first week of June, the Northeast Region was dealing with impending drought concerns (note wrapped corn from June 4th). Twelve days and 5+ inches of precipitation for many acres, an entirely new set of concerns for the 2026 crop. New concerns relate to saturated soils, erosion and crop damage caused by moving surface water and wind, and the lack of opportunity to apply post herbicides while weeds are in the optimum treatment window. Even when standing water dissipates, a saturated soil very quickly limits oxygen availability to a growing crop. An oversimplified way of describing the effects of a saturated soil is that the lack of soil oxygen available to the roots can reduce or stop plant functions. This can include transpiration, nutrient uptake, and water uptake. Extended saturated soil can cause visible stunting and even plant death, resulting in varying degrees of reduced final yield. In addition to struggling crops, persistent precipitation has prevented many post-herbicide applications from taking place. A few weeds, especially waterhemp, easily have exceeded the recommended maximum weed size for control of most herbicide. Soy on well drained soils are starting to enter their reproductive stage (flowering). We are near halfway through the growing season and have experienced the environmental conditions of excessively cool, hot, dry, and wet; What’s next?

A dry week in the Northeast region, corn picked up one additional leaf (V6) and soy pushed out another trifoliate (now V2) in the fields that I am observing on a weekly basis. Hay harvest, nitrogen sidedressing, and post herbicide applications are all taking place. With the comparatively quick onset of dry conditions and stress on both crops and weeds, farmers are encouraged to evaluate post herbicide applications at least a week after application. Environmental stress, including drought, can slow active growth and herbicide solution absorption in plants, decreasing herbicide effectiveness on targeted weeds.

A warm and mostly dry week for growing crops (and weeds). Several mid to high eighty-degree days pushed corn from V3 last week to V5. At V5, all of the embryonic leaves and ears have been initiated in the corn plant, and its growing point (meristem) will soon be above ground. The warm weather also pushed the soy crop, last week a no-till soy field at VE has reached nearly V1 with the first set of trifoliates unfurling. I would be remiss if I did not share that the great growing weather also benefitted weeds as well. Several species, especially waterhemp are matching the crops quickened growth. In this region, most planting has finished and farmers are taking advantage of the rain free forecast to harvest the first hay cutting.
Over the years I have made numerous trips from Grundy County to the University of Illinois campus. My most frequent route includes a stretch of Route 47 straight south to Interstate 74. Yesterday I made the trip and wanted to share my windshield observations. I noted several agronomy practices that seem to be picking up in frequency, they include sidedressing corn with liquid nitrogen, no-tilling soy into a standing cereal rye cover crop, and a growing number of winter wheat acres in rotation. It will be interesting to follow these fields and practices as the growing season progresses.

Another good week for field work in the region. Substantial progress was made in both corn and soy planting. Several eighty degree days helped spur growth in planted crops; however, I noted no-till soy fields, especially soy planted into heavy corn residue, were lagging in emergence and development, likely due to cooler soils. It is generally suggested with soybeans that cotyledons provide the needs of the plant during emergence to almost V1 (first trifoliate) stage. After V1, the photosynthesis of the vegetative plant will sustain itself. Early planted corn in the region has reached V4. Underground, the seminal root system has been joined by the nodal root system. The nodal root system of the corn plant is initiated at VE and becomes the major supplier of nutrients and water to the plant by V6.

Scouting fields at emergence and early vegetative stages is helpful in evaluating planter (and operator) performance by observing uniformity of plant stands, spacing and overall emergence. Additional notes can be taken on early season diseases, compaction or poorly drained areas in a field, and early season performance of soil-applied herbicides.

Soft red winter wheat has reached anthesis or flowering. For those considering a fungicide application to control Head Scab, this is a recommended window of application. In forage crops, alfalfa has started to flower, an indicator for harvest consideration (depending upon your goal of quality or quantity) when a favorable weather window permits.

A favorable week for field work in the region. Many corn and soy fields were planted and operations continue in the area. Earlier planted corn appears to be emerging with a slight advantage to soy. This week we will be starting the aphid suction collection trap in Morris, part of the Suction Trap Network that will be monitored through October. This trapping program is led by Dr. Doris Lagos-Kutz, Illinois Natural History Survey-Prairie Research Institute. The program generates data on aphids and other beneficial and pest insects across multiple states. (https://suctiontrapnetwork.org/)
While corn and soy crops are waiting for consistently warm weather to expedite growth, several weed species have flowered or grown rapidly in untreated or unworked fields. They include the yellow flowered winter annual Butterweed, and the early emerging summer annual Giant Ragweed.

I’m looking forward to another growing season and crop reporting in Northeast Illinois. April and May precipitation has slowed planting progress compared with other regions of Illinois. I’m estimating almost as much seed is still in the bag as is in the ground. On suitable days for planting, reports received suggest local farmers actively planted both soybeans and corn. The practice of planting soybeans ahead of corn acres has been adopted by many. Whether corn or soybeans, I was impressed by the acreage planted in a limited time frame. Despite planting date, low accumulations of GDDs have slowed crop emergence.

With limited emerged crops, we will highlight insect pests found in alfalfa. While sweeping alfalfa, we netted alfalfa weevil larvae, aphids and bean leaf beetles. We will continue to monitor leaf feeding in the alfalfa crop to determine whether a management threshold is reached.

Harvest is on the horizon, and maturity and dry down will likely be expedited with the return of forecasted warmer temperatures. Looking back 150–170 days and evaluating the current growing season, most crop stressors were environmental (dry or drought conditions) or related to plant disease (primarily in the corn crop). Recent field surveys suggest higher yields in fields that received isolated or intermittent rainfall or had soils with greater water-holding capacity. Soon, combines will be rolling, and the true impact of the growing season’s challenges will be known. We encourage everyone to prepare for a safe harvest season.

Precipitation this past week brought substantial rainfall totals to some fields in Northeast Illinois. Isolated corn fields are showing significant disease pressure but are also nearing maturity. In the R5 stage, the corn kernel contains both “soft” and “hard” starch. The transition, or hardening, of the soft starch into hard starch begins at the top of the kernel and progresses to the tip. This progress is visible as the kernel’s “milk line.” Corn is typically about 55 percent moisture at the beginning of R5 and 30 to 35 percent at its conclusion. Corn plants generally complete the R5 stage in about 30 days, during which they accumulate dry matter content.

The soybean crop is nearing the R6 stage. At R6, or full seed, plants have a green seed that fills the pod at one of the top four nodes on the main stem. Once soybeans reach R6, new leaf growth ceases, and lower leaves begin to yellow and drop. We are encouraging growers, especially those with a history of the disease, to monitor their fields for white mold.

For those attending the Farm Progress Show next week, visit Illinois Extension at the University of Illinois College of ACES tent on West Progress Avenue.

This week, Dr. Giovani Preza Fontes, assistant professor and agronomy extension specialist at the University of Illinois, visited the Grundy-Kendall County area and met with area producers, where he shared expectations for both state and local yields. Farmers were provided with recent weather data and were encouraged to take kernel and population counts to determine yield estimates in their own fields.

The pattern of variable rainfall and pop-up isolated thunderstorms discussed was demonstrated that day, with rainfall ranging from 0 to 2-plus inches within a 40-mile radius. Most corn is at the R5 stage, and the likelihood of a return on investment from a fungicide treatment (or additional treatment) at this stage is unlikely. That said, scouting corn that did not receive a fungicide treatment in some fields is like taking an introductory course in plant pathology. Symptoms of tar spot, northern corn leaf blight, gray leaf spot, and southern rust can all be found.

Recent environmental conditions have been especially favorable for the development and spread of southern rust. All leaf diseases are reducing photosynthetic leaf tissue that would aid in grain fill.