With harvest getting underway around the state, ISU Extension and Outreach field agronomists share a quick update on initial harvest progress as well as other observations they have made or are hearing about in their respective regions including fall armyworms being found in forages and concerns about stalk integrity in cornfields. Read on for more specifics.
Leah Ten Napel (Region 1):
Cherokee, Ida, Lyon, Monona, O'Brien, Osceola, Plymouth, Sioux, Woodbury counties
“Fall farming operations are underway in northwest Iowa. Silage, earlage and early maturing corn and soybeans have been harvested. Yields of soybeans being reported so far are high, while corn yields are average to slightly above average. Weather has been on the dry side, and many producers would welcome more moisture to carry grasses and cover crops further into the fall. Dry down is happening quickly, and farmers are scouting fields to keep tabs on stalk integrity. Fall armyworms are causing issues in pastures in cover crops. Read this article on Fall Armyworm to learn more. Have a safe and plentiful harvest!”
Angie Rieck-Hinz (Region 3):
Cerro Gordo, Franklin, Hamilton, Hardin, Humboldt, Webster, Worth, Wright counties
“From September 1 through September 23, we have had 4.85 inches of rain at Fort Dodge, which is 1.81 inches above average and 1.49 at Iowa Falls which is 1.11 below average for that time period. The rains we are catching have been locally heavy in some places causing delays in harvest. Corn harvest has been on-going in some places since September 8, and in other places it has barely started. There are very few beans harvested. Corn yield reports range from 135 to 210 and test weight from 50 to 58. I have had a few reports of purple soybeans stems. This can be variety related, but is often due to a source-sink distribution issue as the plant produces carbohydrates that can’t be used. For a great explanation see this Crop Protection Network article and video “The Science Behind Late Season Purple Soybean Stems”.
Josh Michel (Region 5):
Allamakee, Buchanan, Clayton, Delaware, Dubuque, Fayette, Jones, Linn, Winneshiek counties
“Over the past couple weeks, a few rain showers have come through the area causing some minor rain delays to the start of harvest season. In general, most of the area has received 0.50 to 1.5 inches of rainfall, with a few isolated areas receiving up to 2 inches of precipitation. Some early fields of corn are starting to get harvested with moistures below 20%, while some early-planted soybeans are quickly drying down to 15% or less. Stalk integrity and standability continue to be a concern. Forages continue to look good as regrowth from the last alfalfa cutting is quickly coming back and pastures are taking advantage of the recent rainfall. Reports of fall armyworms have been sporadic and isolated, but producers should be aware of conditions that may quickly change and warrant management. Most of the recent field calls have centered around fall weed management in pastures, fall armyworm management, and harvest conditions.”
Meaghan Anderson (Region 7):
Boone, Dallas, Jasper, Madison, Marshall, Polk, Story, Tama, Warren counties
“Central Iowa received some rainfall over the past couple weeks, including a storm that came through Monday evening and caught a swath of central Iowa. Crop harvest is in full force and farmers overall are reporting dry corn, lower than expected yields, and big benefits from fungicide this year due to the remarkable southern rust pressure. Soybean harvest is not nearly so far along, but yield reports have been good but nothing swinging too wildly high or low. I haven’t heard about too many harvest issues, but the corn crop is dusty and some farmers are dealing with dry grain and rubbery cobs. Our blog webpage has a number of new articles on harvest topics related to improving combine settings that are worth a read. Manure application has started in central and north central Iowa. My recommendation is to hold off on application for as long as possible due to the significant risk of nutrient loss when soil temperatures are as warm as they are right now; we are not expecting soil temperatures below 50 degrees Fahrenheit until early November – approximately SIX weeks from now. Read more on manure application tips in this recent article from Dan Andersen.”
Rebecca Vittetoe (Region 8):
Iowa, Jefferson, Keokuk, Poweshiek, Washington, Johnson counties
“Harvest is ramping up in the counties that I cover for both corn and soybeans. Initial yield reports have been variable with some good yields and some disappointing yields. The rain last week and over the weekend put a slight pause on harvest with rainfall totals being quite variable and ranging from a couple tenths to over 2.5 inches in areas. Continue to monitor corn fields for standability as stalk integrity is poor in some fields already. While most have already taken their last hay cutting, do continue to monitor hayfields and pastures for fall armyworms. I continue to receive reports on them. Also, now is a great time to start thinking about fall pasture weed management, especially for some of our troublesome perennial and biannual weeds. Hope everyone has a safe harvest season!”
Virgil Schmitt (Region 9):
Cedar, Clinton, Des Moines, Henry, Jackson, Lee, Louisa, Muscatine, Scott counties
“In general, the counties I cover received less than 0.5 inch of rain in the last two weeks except south of Highway 34 received a little more. Most corn is at R6 (physiological maturity/black layer). Harvest is well underway in most areas, with more in the southern counties and less in the northern counties. Initial reports are that test weights are good and there are some excellent yields and some disappointing yields, with much variation from hybrid to hybrid. Soybeans are generally R8 (full maturity) and are losing or have lost all their leaves. Harvest began seriously last week in some areas. Initial reports are that soybean yields are good, but not great, and rapid dry down (below 13% moisture) is causing market value losses. Forages continue to look good. Calls during the last two weeks mostly centered around pasture weed management.”
Logan McCrea (Region 11):
Appanoose, Davis, Lucas, Mahaska, Marion, Monroe, Van Buren, Wapello, Wayne counties
“After the rather warm and dry finish to the growing season, some welcome precipitation accumulated over the past week with totals ranging from a half inch to a few inches in some locations. This slowed down the harvest pace a bit, but producers should get another good window to run later this week. Corn yields are all over the board, and standability is still the biggest concern. The storms whipped some fields around a bit and definitely made poor stalk quality noticeable in certain fields. A few soybean fields have been harvested, although the weather put a stop to that and we will need to dry out a bit before getting back to good soybean harvesting weather. Early yields seem promising. Forage wise, pastures are loving the drink of water they just got after the warm and dry weather. I still am hearing about fall armyworms causing issues in forage fields. With most producers having wrapped up their last hay cutting, this has made for some interesting conversations regarding what to do in their fields.”
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- Field Agronomist in EC/SE Iowa