With harvest underway across the state, check out what ISU Extension and Outreach field agronomists are hearing regarding how harvest is going, how are the crops yielding, and what types of end-of-the season issues they are receiving questions on.
Northwest Iowa
Gentry Sorenson (Region 2): “Corn and Soybean harvest is underway in NW Iowa. Most farmers are focusing on soybeans harvest currently as conditions have been good to make significant harvest progress. I have heard a variety of yield results across the area, with good yields reported in areas that had adequate rainfall. Areas that have had drought stress to severe drought stress are reporting impacted soybean yields from the drought. I have had phone calls related to green stem syndrome soybeans in the counties that I serve as well as purple soybean stems in soybeans. After evaluation of a few corn fields before harvest, I noted tar spot and northern corn leaf blight were found in several fields. A map of the counties in Iowa that tar spot was detected can be found here. As seed decisions are made for the 2023 growing season it is important to understand the disease ratings of corn hybrids and soybean varieties going into the growing season to make important agronomic decisions next growing season. Phone calls consisted of questions about corn and soybean disease and green stem syndrome soybeans.”
North Central Iowa
Angie Rieck-Hinz (Region 3): “Harvest is in full swing in NC Iowa. The crop report as of Monday indicated 8% of the corn was harvested and 27% of the beans are harvested. In some areas farmers report they are finished harvesting beans, some have just started beans after taking out some corn, some are mostly done with corn, and some are just starting corn. It is a mixed bag, just like the entire growing season. Yields are also highly variable and dependent on rainfall across the area. Harvest conditions have been ideal thus far, with lower humidity and continued dry down of crops. While areas continue to show up on the drought monitor, the drier areas for September included areas like Northwood, Mason City and Hampton which all averaged over 2.25 inches below normal for September rainfall- a possible indication that drought conditions are continuing to creep eastward.”
Northeast Iowa
Josh Michel (Region 5): “Over the past two weeks, only a few areas in NE Iowa have received up to 0.10 inch of rainfall. On September 28th, we also saw temperature lows down to 29°F in some isolated areas; resulting in a killing frost for any corn and soybean fields that were not fully mature yet. Corn grain harvest has just started throughout the region as the last fields being harvested for silage are finishing up. With less than 10 percent of fields combined so far, yield reports have been widely variable. An estimated 80 percent of soybean fields have dropped their leaves. Less than 10 percent of soybean fields have been harvested so far as well. As expected, yield reports have also been widely variable. I’d expect corn and soybean harvest to come into full swing this week as we have favorable weather conditions. The cold temperatures also prompted several questions pertaining to feeding forages that may have received cold injuries. Thankfully, a killing frost for alfalfa is considered to be around 24°F for at least a few hours. While we didn’t receive a killing frost, there could be some isolated areas with light frost damage. This was a big sigh of relief as many of our alfalfa fields will need some addition growth before winter. Pastures continue to look good, although some are starting to look a little dry. Most of my field calls over the past week have consisted of finishing up silage harvest, forage management and cold-injury concerns, and weed management in pastures.”
Southwest Iowa:
Aaron Saeugling (Region 10): “Harvest is well underway in SW Iowa. Corn harvest began with silage and high moisture corn being harvested first with variable yields from lows in the 50 bushel/acre range in dry areas to better rainfall areas being closer to the 200 bushel/acre range. Some standability issues have been observed in corn and those fields will be targeted for early harvest. Corn disease seems to be more prevalent than initially thought with grey leaf spot and tar spot being the most prominent. Soybean harvest really got a jump start over the weekend, and I expect with good weather this week many of the soybeans will be harvested. Getting reports of green stems and dry soybeans being common. Yields are average for most farmers, and will be mid 50’s to low 60’s. Pastures are in poor to very poor conditions depending on the September rainfall totals. I expect a large volume of corn stalks to be baled for winter feed. Be careful when considering fall tillage due to poor subsoil conditions and the lack of precipitation potential in the long-term forecast.”
Central Iowa
Meaghan Anderson (Region 7): “Low rainfall totals in the last two weeks have allowed for crops to mature, dry down, and for harvest to get started in central Iowa. Crop harvest is in full gear with both corn and soybeans coming out of the fields. Corn is still in the 20s for moisture in many fields due to late planting and long relative maturities. Frost nipped some replant soybeans last week, but many soybeans are coming out already at 9-13% moisture. I’ve received reports of soybeans with green stems and holding green leaves that have seeds already at harvest moisture and reports of soybean stems that are brittle and dry but the seeds are still holding moisture and above 13%. Many corn fields had tar spot and northern corn leaf blight come in late – too late to affect yield but enough to remind us of their presence for future years. Corn yields seem to be all over the board – ranging from excellent to disappointing. Some fields are suffering from the dreaded “edge effect” with southern field edges yielding in double digits. Soybean yields have been mostly in the upper 50s to low 70s, better than some farmers expected. As harvest progresses, continue to monitor fields for weed issues that persisted through the growing season as these areas will be problematic next spring.”
East Central, Southeast, and South-Central Iowa:
Rebecca Vittetoe (Region 8): “Combines first started rolling about two weeks ago in part of EC Iowa, but they really started rolling over the last week. I’d estimate that about 15-20% of the soybeans have been harvested across the counties I cover, and about 15% of corn has been harvested. Based on the yield reports I’ve heard, yields are variable. One comment I’ve been hearing a lot about soybeans this year is the number of leaves, especially green leaves, still on the plants even though the grain moisture is ideal for harvest. On the corn side, continue to scout for stalk rots and watch stalk quality, and I’ve also had some questions asking about “the edge or border effect” in corn, especially in some of the drier areas in EC Iowa. Forages could benefit from some rain here this fall. Also, don’t forget that fall can be a great time to control some of our perennial or biennial weeds in pastures or hayfields.”
Check out the map below to find your local ISU Extension field agronomist and find their contact information here!
Rebecca Vittetoe Field Agronomist in EC Iowa
Rebecca Vittetoe is an extension field agronomist in east-central/southeast Iowa serving Iowa, Jefferson, Johnson, Keokuk, Poweshiek, and Washington counties. Vitteoe works with farmers, landowners, and ag retailers to answer agronmy-related questions. Her areas of expertise include general ...