Regional Crop Update: May 6 - May 14, 2024

May 14, 2024 9:32 AM
Blog Post

Last week was another wet week with rainfall totals ranging from just over 0.5 inch to 2.5+ inches of rain across the state. Folks were finally able to get back in fields late last week and over the weekend to do tillage, plant, spray, and even get hay cut and baled or cover crops harvested for feed. Planting considerations, alfalfa weevil, pasture/hay/CRP management, herbicide injury, and weed management have been some of the common questions or topics reported by ISU Extension and Outreach field agronomists this last week. Read on for more specifics on what’s happening in different areas across the state.  

North Central Iowa

Angie Rieck-Hinz (Region 3): “Persistent rainy weather has kept most people out of the field for nearly 3 weeks. Rainfall amounts from May 1 to May 14 average just short of 5 inches, with localized heavier amounts of 6-7 inches. There was field activity and some planting happening around Mason City, Manly and Hanlontown on May 13. Corn is VE to V2 and most soybeans are just cracking to VC. Uneven emergence is showing up due to wet soils and uneven planting depth in excessively worked soils. Most phone calls have been related to hay, pasture and CRP management."

Northeast Iowa

Terry Basol (Region 4): “Field operations for last week were pretty much at a standstill due to precipitation events across the area. According to the Iowa Mesonet, the NE Iowa Research and Demonstration Farm at Nashua has received 2.52 inches of rain for the period of May 5 through May 12 (last week), and 3.78 inches since May 1. Corn ranges from VE to V2 depending on planting date, and early planted soybeans are emerging as well. According to the USDA-NASS May 13 Crop Progress Report, 57 and 41 percent of the acres have been planted to corn in NC NE Iowa, respectively. For soybeans, 22 and 36 percent of the acres have been planted in NC NE Iowa, respectively. Keep an eye on alfalfa stands, as they are getting close to first cutting. Also, continue to monitor for alfalfa weevil activity, particularly, the southern half of my territory along the Hwy 20 corridor. Crossing fingers for good weather to help get the rest of the crop in the ground for 2024."

Josh Michel (Region 5): “Persistent rain showers continue to keep most field operations at a standstill throughout most of NE Iowa. Over the past week, most of the region has received anywhere from 1 to 2.5 inches of rainfall. Not surprisingly, this has resulted in some improvements in the latest U.S. Drought Monitor. Between rain showers, some farmers did manage to get a few more acres planted. I’d estimate that 45% of the corn has been planted so far, while soybeans stand at 35%. Early planted corn is quickly approaching V1-V2, while the furthest along soybeans I’ve seen are at VC. Alfalfa fields and pastures continue to benefit from the latest rainfall and are growing very quickly. Farmers should continue to scout for alfalfa weevils as I’m starting to find moderate levels of defoliation in some isolated areas. Other recent field calls have centered around cover crop termination, forage management, weed ID and management and a couple calls regarding possible pesticide drift.”

Alfalfa weevil defoliation NE Iowa
Defolation on an alfalfa plant from an alfalfa field in NE due to alfalfa weevil larave feeding. Photo by Josh Michel. 

Central Iowa

Meaghan Anderson (Region 7): “Central Iowa got another ~1 to 3+ inches in the last week on top of the ~4 to 9 inches we’ve already received since April 1. Story County and NE Boone County seem to be hot spots, while Tama County and the corridor between I-80 and Hwy 92 seem to be drier. I received no rain yesterday in northern Polk County but the southern part of my area received some heavy rainfall yesterday. Fieldwork finally started again slowly on Friday and continuing through the weekend. Mostly people spraying and starting to plant again. Most corn and soybean that were in the ground in April have emerged, and if farmers can get into the fields, it would be a good time to scout them. Corn is up to about V2 and the furthest along soybeans I’d seen were VC last week. I’m noticing a lot of PPO herbicide injury on emerging soybean. Most calls have been about alfalfa weevil, but phone calls have started about other issues like insect feeding, herbicide injury, and abiotic issues in corn and soybean.”

PPO herbicide injury on soybean seedling
PPO inhibitor injury (i.e. discolored lesion on seedling above) on soybean seedlings has been more prevalent this spring with the cooler and wetter conditions. Photo by Meaghan Anderson. 

Southwest Iowa

Aaron Saeugling (Region 10): “Some locations in SW Iowa gained a few acres on Friday, Saturday, and Sunday on planting progress. It’s hard to estimate planting progress, but I would guess would be around 70 percent of the corn acres have been planted and around 60 percent on soybean. Some areas had heavy rainfall events, so those areas are further behind and did not make any progress last week. Spraying has been a challenge with mostly wet conditions and large weeds. Pasture conditions continue to improve with several ponds refilling to offset the previous three years of dry weather. River levels and creek levels are closer to normal than in the past. Crops that were planted earlier are emerging and for the most part are looking good. Corn is in the early V1 to V2 stages. Soybean is in the VE to V1 stage. With the mild winter I continue to encourage farmers to scout for insect pressure.”

East Central, Southeast, and South-Central Iowa

Rebecca Vittetoe (Region 8): “East-central Iowa received anywhere from just shy of 1 inch to 2.5+ inches of rainfall over the last week, with the heavier amounts in Benton, Poweshiek, and Mahaska counties. The rain kept farmers out of the field most of the week, but late last week and over the weekend folks were able to get back in the fields. There was a lot of activity with tillage, planting, and spraying over the weekend. Planting progress varies depending upon the neighborhood. The earlier planted corn is at V2-V3 and soybeans at VC. Now is a good time to start assessing the stand of the earlier corn and soybean fields. Be on the lookout for bean leaf beetles in soybeans and now is also the time to start scouting for black cutworm activity. Questions over the last week were mainly on alfalfa weevils, delayed planting, and herbicide injury.”

V2 corn in Keokuk County corn field.
An earlier planted corn field in Keokuk County right at V3.  Photo by Rebecca Vittetoe. 

Virgil Schmitt (Region 9): “Rainfall during the last week in the counties I cover generally ranged from 0.5 to 2.5 inches with larger amounts to the north and smaller amounts to the south. Very little field work was done last week in the counties I cover until Friday and into the weekend. Some hay was cut on Friday and baled on Sunday. Planters and sprayers were going strong over the weekend. Corn planting is about 70 percent complete in my northern counties and about 50 percent complete in my southern counties. Some early planted corn is at V2 and looks good. So far, I have not heard of any black cutworm problems. Soybean planting is about two-thirds complete in my northern counties and about one-third complete in my southern counties. Some early planted soybeans are at VC. So far, I have not heard of any issues with bean leaf beetles. Alfalfa is about 23 inches tall and has an estimated RFV of 195. So far, alfalfa weevil numbers are generally below threshold north of Highway 30. Smooth bromegrass and tall fescue are starting to head out. Contacts last week mostly involved alfalfa weevils and weed management.”

Rainfall totals across the state for May 7 - May 13, 2024.

Clarabell Probasco (Region 11): “The south-central portion of the state has continued to receive rainfall. Most of the area received 1 to 2 inches in the past 7 days. However, some areas missed pieces of rain systems working their way across the region and were able to find small windows to get back into the field this weekend. Friday, Saturday, and Sunday provided a few good days of field conditions for fertilizer and herbicide applications, tillage, and planting. Planting progress is still slightly behind most of the state, coming in at 50% planted for corn and 36% planted for soybeans on the May 13 USDA-NASS Iowa Crop Progress Report. Producers growing cover crops for feed purposes were also able to get fields harvested this weekend. Early planted crops that have emerged are looking good thus far. Alfalfa weevils continue to feed heavily on alfalfa fields; however, some fields are now tall enough for cuttings to be taken when producers can find a window in the weather pattern of rains to allow for a successful harvest.”

Check out the map below to find your local ISU Extension field agronomist and find their contact information here!

Field agronomist territory map



Rebecca Vittetoe Field Agronomist in EC Iowa

Rebecca Vittetoe is an extension field agronomist in east central Iowa. Educational programs are available for farmers, agribusiness, pesticide applicators, and certified crop advisors.

Areas of expertise include agronomy, field crop production and management of corn, soybeans, and...