Although the entire month of May saw just under an inch of rain in total, the beginning of June has brought some relief with over two inches of rain deposited thus far with more on the way (based on data from the Water and Atmospheric Resources Monitoring Program Freeport station – your mileage may vary!).

Stephenson County is the home of the first reported population of Asian copperleaf in Illinois (https://extension.illinois.edu/news-releases/novel-illinois-weed-species-asian-copperleaf-identified-northern-illinois). Although originally thought to be a late emerging weed typically not noticed until after harvest, seedlings have already been emerging over the last couple of weeks. When scouting prior to making post emergence herbicide applications, keep an eye out for Asian copperleaf. For help with identification, see the attached photos as well as the Asian copperleaf fact sheet from Illinois Extension at https://extension.illinois.edu/media/9233/download?inline.

If you suspect you have Asian copperleaf, please contact Kathryn Seebruck at 815-986-4357 or seebruck@illinois.edu. Reports can also be made at https://www.eddmaps.org/.

Fieldwork and planting have been ongoing once fields dried enough following the significant rainfall events experienced in the area in mid-April. Although two weeks ago we experienced a number of uncharacteristically warm days, the weather this week continues to vary, as some days have been relatively warm but many nights have been relatively cool, with some even falling below freezing. Those who have recently planted may see slower emergence due to the consistently colder nighttime temperatures. However, the next week should bring temperate weather to facilitate further planting progress and good conditions for crop emergence across the area.

Across much of the area, there are entire fields of soybeans exhibiting cupping. The widespread nature of the symptom could point to environmental stress as the cause, potentially from the hot and dry conditions over the past week and a half. Many soybean fields are still not canopied.

Corn has greatly increased in height recently due to the accumulation of over 240 GDDs during the past week and a half. I have not seen, and there have not been any reports of, disease in corn thus far this season.

Tuesday’s storms and Wednesday’s rain resulted in over an inch of rain being supplied to the area, which have helped to supply some needed soil moisture.

The fields referenced in today’s report have experienced some hail damage, though the plants will fortunately grow out of it as the damage was not too severe and there is enough healthy tissue to enable the plant to overcome the damage. Producers in the area are encouraged to scout for hail damage.

The soybeans in this field also seem to be exhibiting some Group 15 herbicide damage, as evidenced by the “drawstring” effect on the leaves whereby the midvein is shortened and the leaf tip is crinkled, resulting in heart-shaped leaflets. The damage is likely due to cold conditions, and fortunately, soybeans grow out of this injury quickly. Although this field is exhibiting some damage and injury, the soybeans have already produced active nodules, which may have been helped along by the producer’s use of in-furrow fertilization.

Across the county, corn is between VE and about V4 while soybeans are yet to emerge or at about V1. The rainfall received over the past couple weeks has been well received – the crop looks healthy and green. Surprisingly given the rain, there aren’t yet any significant weed flushes, but scouting is recommended to identify any moving forward.

Northwestern Illinois is in the home stretch of planting. I’ve been able to row quite a few corn fields, and beans have been reported as being up and out of the ground or just about. There are few fields that have yet to be planted.

Weeds such as giant ragweed and common lambsquarters are present in fields I’ve been in, and in one field that had not been worked yet, I saw the invasive weed poison hemlock, which was also present in the adjacent ditch. This serves as a reminder to maintain edge-of-field areas, as they can serve as entry points for invasive species.

Soybeans are at R6-R7 throughout the area, and corn is at R4-R5. We have not had any significant rainfall events for a couple of weeks, leading to dryer conditions. I still have not heard any reports of or seen increased incidence of disease or insect issues. Some silage chopping has begun.

After last week’s storms, the corn that was most heavily impacted (which was minimal) has mostly come back up. Everything still looks very healthy as we continue to receive rainfall. Corn is silking and soybeans are anywhere between R3 and R5. I have seen some rootworm beetles and subsequent silk clipping but not in high amounts. Soybeans have some Japanese beetle feeding but it’s very minimal. I also have not seen any significant disease pressure.

Some side-dressing is still occurring on later planted corn, and beans are currently being sprayed. Some are struggling to finish wheat harvest due to the wet weather we keep getting. Not all areas have been affected similarly with rain, but the range is between just enough and too much to the point of creating drowned out low areas; we have not experienced much dry weather this season. A lot of corn is tasseling and fungicide applications are due to begin if they haven’t already, with no insect or disease issues yet being reported. With the consistent wet weather we’ve been experiencing, it is recommended to scout regularly for occurrence of disease.

With the significant rainfall the area saw beginning a couple weeks ago (> 2.6 inches between May 21 and 28), plus almost another inch of rain between June 1 and now, corn is beginning to show signs of N deficiency. Some fields are showing areas of stunted, light green plants, and some are exhibiting uneven emergence. This is not across the board, however, and some fields look very healthy. This week, I have seen little to no ponding in fields.