Extension center educators, unit educators, and unit assistants in northern, west-central, east-central, and southern Illinois prepare regional reports to provide more localized insight into pest situations and crop conditions in Illinois. The reports will keep you up to date on situations in field and forage crops as they develop throughout the season. The regions have been defined broadly to include the agricultural statistics districts as designated by the Illinois Agricultural Statistics Service, with slight modifications:
- North (Northwest and Northeast districts, plus Stark and Marshall counties)
- West-central (West and West Southwest districts, and Peoria, Woodford, Tazewell, Mason, Menard, and Logan counties from the Central district)
- East-central (East and East Southeast districts [except Marion, Clay, Richland, and Lawrence counties], McLean, DeWitt, and Macon counties from the Central district)
- South (Southwest and Southeast districts, and Marion, Clay, Richland, and Lawrence counties from the East Southeast district)
We hope these reports will provide additional benefits for staying current as the season progresses.
We have received few reports of silk clipping by Japanese beetles or of corn rootworm beetles interfering with corn pollination. Continued moderate temperatures have been beneficial for the later-pollinating corn.
The main concern throughout the northern region is on increasing populations and distribution of soybean aphids. Growers and industry personnel are encouraged to read the last few issues of the Bulletin for comments concerning soybean aphid thresholds and scouting techniques. A few fields have been treated with an insecticide for soybean aphid populations, and those fields are across a wide geographic area in the northern region. Soybean aphid populations are very variable within a field and across the region. Reports have been received that predatory insect populations, such as the multicolored Asian lady beetle, have increased in infested fields the past week. Also, several comments have been received concerning the difficulty in identifying the alatoid nymphs, which develop into the winged adult soybean aphids. For ala-toid nymph identification, soybean aphid biology, and thresholds, you are encouraged to read the U of I soybean aphid fact sheet .
Just a reminder that the annual Agronomy Field Day at the U of I Northern Illinois Agronomy Research Center in Shabbona will be held next Monday, August 4. Tours will depart from the farmstead every 20 minutes from 4:00 p.m. to 5:00 p.m. and last about 1-1/2 hours. A meal will be available on site at the conclusion of the tour. The Research Center can be reached by going 1 mile east of Shabbona on Route 30, then 5-1/2 miles north on University Road.
Rainfall throughout the south has been spotty during the last 2 weeks, and crops in some areas of the region are beginning to show evidence of moisture stress. This is especially true on the sandier soils in the southeast. Cooler temperatures during this week will help minimize problems, but regular rainfall will be needed to ensure good yields from late-planted crops.
Japanese beetle feeding on corn silks is quite impressive in areas where they are found in high concentrations. In some cases, the earliest-planted fields suffered the brunt of the damage as beetles concentrated their feeding at these sites. Fall armyworm damage is showing up in late-planted corn and grain sorghum, and there are some reports of corn leaf aphids being found.
Double-cropped soybeans are finally beginning to show above the wheat stubble. Delayed applications of post-emergence herbicides have resulted in weeds such as waterhemp being larger than optimum for best weed control.
Don't forget to mark your calendars to attend the Dixon Springs Agricultural Center Field Day on Thursday, August 7, beginning at 7:30 a.m. For more information, contact Steve Ebelhar at (618)695-2790.
Rainfall was received in most areas of the region last weekend, assuring producers that a crop of corn and soybeans much better than average will likely be produced throughout most of the region. The greatest concern continues to be the extent of wind and hail damage from recent storms. Corn development ranges anywhere from tasseling to early dough stage, and most early-planted soybeans are at beginning pod.
Because of the moist conditions, some instances of crop diseases are occurring in corn, such as gray leaf spot, common smut, and anthracnose, and in soybeans anthracnose, bacterial blight, septoria, and phytophora. Insect problems have been mainly limited to silk clipping of corn by rootworm beetles and high numbers of bean leaf beetles found in soybean fields.