C.O.R.N. Newsletter: 2023-20
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Battle for the Belt: Episode 16
Episode 16 of Battle for the Belt is now available:
In Episode 16, we talk to Jenna Moore, a Ph.D. student working with Dr. Horacio Lopez-Nicora in the Soybean Pathology and Nematology Lab at Ohio State. Her research focuses on the impact of planting dates on soybean and corn seedling diseases.
The Battle for the Belt project structure provides a great opportunity to better understand how environmental conditions (e.g., rainfall, soil temperature, etc.) at different planting dates and soilborne pathogen diversity impact soybean and corn seedlings. Jenna Moore explains several methods used to isolate pathogens from seedlings and surrounding soil at the VE stage (emergence) for both crops. Soil baiting is a method used to isolate water molds (i.e., oomycetes), which includes common pathogens like Pythium and Phytophthora. A second method, seedling surface sterilization, and plating is used to isolate fungi (e.g., Fusarium, Rhizoctonia, etc.) and oomycetes from within seedlings. Isolates are then transferred to new plates to achieve pure culture for further molecular characterization to the species level.
Jenna and the lab have partnered with our team to conduct seedling assessments across different planting dates and the different sites for corn and soybean. Later, the relationship between the identified pathogens and the environmental conditions at each planting date will be evaluated. Preliminarily, we are seeing many Fusarium isolates collected from within seedlings at early planting dates. Molecular identification will provide confirmation in the coming months, and we are looking forward to sharing results towards the end of the summer.
Battle For the Belt Location Updates
We have officially finished planting! The final date was planted at the Wooster site on June 21st (Figure 1). The conditions were favorable since this was after a week of much-needed rain. Though we are facing cooler than normal, temperatures are still optimal, and the plants are advancing in the stage. The last planting date at Northwest and Western for corn and soybeans are V1 and VC stages now.
Planting date one (April 12) in soybeans has achieved flowering in some plots at the Northwest location (Figure 2), many early April planted soybeans will be reaching R1 in the next week or so. The R1 stage is an ideal time to be scouting for disease pressure. Though the state has seen a dry spell, the incoming storms have the potential to create an environment for diseases to develop and grow. For example, cool and wet weather is the right environment for frogeye leaf spot to grow as well as white mold. Something to note is that Northwestern Ohio has had white mold in the last couple of years.
Planting dates two, three, and four in soybeans at the Northwest research station are V5, V4, and V2/V1. The corn is progressing well with planting date one at V8, planting date two at V7, planting date three at V6, and planting date four at V4.
At the Western research station for corn, planting dates one, two, three, and four are at V8, V7, V6, and V5, and for the soybeans, V5, V4, V3, and V1. The corn roots have not fully recovered from the floppy corn syndrome in planting dates one and two at this location. This condition was not seen at the other locations.
At the Wooster site, planting dates one, two, three, and four were V4,
V3, V2, and VC in soybeans. The corn stages are as follows for planting
dates one, two, three, and four: V7, V6, V5, and V3.
Table 1. The planting date environment for planting date five at all three locations. Location
Planting date
2-inch soil temperature (at planting)
Air Temperature (at planting)
Wooster,
Wayne
June 21
70°F
71°F
Western,
Clark County
June 8
69°F
63°F
Northwest,
Wood CountyJune 8
64°F
63°F
Table 2. The planting date one, two, three, and four in the trial at all three locations with the day of planting, soil, air temperature averages, and Growing Degree Days (GDDS). Information from CFAES Weather System, https://weather.cfaes.osu.edu/ Location
2-inch soil temperature
(June 19-June 25)Air Temperature
(June 19-June 25)
Planting date
GDDs
(Cumulative)
Precipitation
(Inches)
Wooster,
Wayne County
Max: 74°F
Mean: 71°F
Minimum: 67°F
Max: 84°F
Mean: 69°F
Minimum: 58°F
April 14th
April 27th
May 11th
May 30th
708
645
592
398
0.17”
Western,
Clark County
Max: 78°F
Mean: 70°F
Minimum: 66°FMax: 89°F
Mean: 70°F
Minimum: 60°F
April 13th
April 27th
May 11th
May 25th
923
837
753
559
0.17”
Northwest,
Wood CountyMax: 71°F
Mean: 70°F
Minimum: 65°FMax: 88°F
Mean: 72°F
Minimum: 59°FApril 12th
April 26th
May 11th
May 25th
889
795
728
559
0.82”
As a recap, this research project includes five planting date windows, 1) Ultra early = late March to early April; 2) Early = mid to late April; 3) Normal = early to mid-May; 4) Late = late May-first week of June; and 5) Very late = mid to late June. All locations have all five planting dates completed now. Stay tuned for results to learn what yielded best.
Keep following the ‘Battle for the Belt’ this growing season to learn more and get further updates! You can find the full video playlist of Battle for the Belt on the Ohio State Agronomy YouTube channel.
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Potassium in Corn
Much of our early planted corn has exhibited signs of potassium deficiency after going through the May to early June dry spell. This article is a basic reminder of how potassium works in the plant so you can make informed decisions on whether you need to apply more potassium.
Potassium uptake occurs by diffusion where nutrients move to the root surface along a concentration gradient from high to low concentration. The effect of dry weather on root growth results in potassium deficiency symptoms. Other conditions such as compaction, herbicide root injury, or insect damage can compound root development issues and potassium uptake.
Identifying K Deficiency
Potassium is mobile in the plant which is why the lower leaves show deficiency first. The plant moves available nutrients to prioritize new growth. Potassium deficiency symptoms include yellowing to necrosis of the leaf on the outer edges or leaf margins, as opposed to nitrogen which starts from the leaf tip to the midrib.
If the symptoms were a result of dry weather and not a soil deficiency, the new growth should appear normal as soil moisture is replenished and root growth improves. Corn begins to rapidly uptake potassium after V6 as demand increases (Figure 1). While the symptoms on the lower leaves will remain, no yield loss is expected due to a deficiency at the early stages (Swayer, 2000).
Soil TestingIf you have a recent soil test that did not show a deficiency, then any visible symptoms are likely a result of dry weather or slow root growth. However, if your soil samples were pulled during extremely dry weather like we had last fall and this spring, it could impact your results. We covered this in episode 109 of the Agronomy and Farm Management Podcast. Listen in for more details. You can also learn more about how soil test potassium levels and pH are affected by low soil moisture by clicking here.
In summary, if your corn has outgrown the deficiency symptoms, then no action is needed and you should not expect an impact on yield. If the new growth continues to show symptoms, then you can confirm the visual symptoms with a tissue test and follow up with a soil test under adequate conditions.
References:
Bender, Ross R. et al. “Modern corn hybrids' nutrient uptake patterns.” Better crops with plant food 97 (2013): 7-10.
Sawyer, J. (2000.). Corn leaf potassium deficiency symptoms. Potassium deficiency symptoms in Corn | Integrated Crop Management. https://crops.extension.iastate.edu/encyclopedia/potassium-deficiency-symptoms-corn
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Midwest Mechanical Weed Control Field Day returns!
This year’s Midwest Mechanical Weed Control Field Day - The nation’s premier event for mechanical weeding tools - will take place on Wednesday, September 27, at The Ohio State University, CFAES Wooster campus.
At the morning Expo trade show, you can see weeding tools, speak with company reps from the US, Europe, and Japanese manufacturers, and meet the farmers in attendance from all over the region. At the morning education sessions, learn from experienced farmers and university weed scientists from surrounding states during the roundtable discussions - topics range from camera-guided cultivators to tine-weeders. A walk-behind tractor exhibition - ‘Walk-Behind Alley’ - features demonstrations of walk-behind tractors and implements from the past and present. You can also visit the trade show exhibit booths to meet other supply companies, like equipment dealers for all manner of machinery, seed, tools, fertilizers, and soils.
At noon, the field day will break for lunch - an opportunity for farmers to meet and network or continue looking at trade show equipment and speaking with exhibitors. In the afternoon farmers follow the tractors out to the demonstration field, where corn, beets, and brassicas have been planted especially for the demonstrations. Myriad 3-point, camera-guided, autonomous, and belly-mounted cultivators and cultivating tractors will be demonstrated in the field and explained by manufacturers. These demonstrations will show how the machines should be mounted and properly adjusted according to crop and soil conditions and will help farmers visualize how the implements can work on their farms.
Row-crop tools in the demonstration include precision-controlled tine-weeders and several types of camera-guided cultivators with finger weeders and all manner of another tooling - see all types of knives, hilling discs, etc. Demonstrations will be held in 5’’ corn. Check the field day website for a current listing of exhibitors and tools. Vegetable weeding tools include cultivating tractors past and present, 3-point in-row camera-guided machines, a variety of belly-mounted and rear-mounted steerable tools, and cultivators from Japan! Demonstrations will be held in 2’’ beets and transplanted brassicas. Check the field day website for a current listing of exhibitors and tools.
Registration for this full day of learning and networking on mechanical weed control is just $50! Registration includes lunch and all the machinery demos you can handle. It is recommended that everyone register early as each year space runs out.
Here is the general information for the event:
When: Wednesday, September 27, 2023,
Where: OSU Wooster Campus, 1680 Madison Ave, Wooster, OH 44691
How Much: $50 (includes lunch)
Register online at: https://thelandconnection.regfox.com/2023-midwest-mechanical-weed-control-field-day
For more info on the event or to register by phone, contact Crystal at crystal@thelandconnection.org or (217) 840-2128.
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Weather Update: Unsettled Weather Continues
Summary
Over the last two weeks, a more active pattern has brought numerous rounds of showers and thunderstorms across the Buckeye State. Many areas, from west central to southeast Ohio have received 2 inches of rain or more, with pockets of 4-6 inches across western Franklin, Fairfield, and Perry Counties. This has resulted in a decline in drought areas from 78% to 33% as of Thursday, June 22, 2023 (US Drought Monitor), leading to some improvement in crop conditions. However, large portions of southwest, northwest, and northeast Ohio have received less than normal precipitation over this period (Figure 1)
, intensifying drought conditions across these areas. Our CFAES Rapid Response Team continues to manage the early drought response resource site and encourages readers to continue to submit observations and impacts for your location by visiting https://go.osu.edu/drought_cmor. Forecast
An upper-level low-pressure system is sliding east across the lower Great Lakes with showers and isolated storms on Monday and Tuesday. Temperatures are expected to remain cool on Tuesday with highs in the 70s and overnight lows in the 60s. Tranquil weather will return for Wednesday with highs in the mid-70s to low 80s across the state. A warming trend will continue for Thursday through Sunday, with highs generally in the 80s, pushing 90°F across the south. With warmer temperatures and increased humidity, isolated showers and storms are also possible throughout this period. The current forecast shows 0.25-0.5” is expected this week across northern counties, with totals over 1” near the Ohio River (Figure 2).
The Climate Prediction Center’s 8-14 Day Outlook and the 16-Day Rainfall Outlook from NOAA/NWS/Ohio River Forecast Center indicate that probabilities for temperatures and precipitation are leaning above average for the period July 3 – 9, 2023 (Figure 3). Climate averages include a high-temperature range of 83-86°F, a low-temperature range of 62-66°F, and average weekly total precipitation of 0.85-1.15 inches. -
Lep Monitoring Network Update #8 – Trap Counts for CEW, WBCW, and ECB (IA & NY)
Introduction
The Ohio Lep Network is continuing to monitor moth pests across Ohio. This being our eighth week of monitoring, we are now beginning reports for Western bean cutworm (WBCW), as well as continuing to monitor for populations of corn earworm (CEW), and both IA and NY variants of European corn borer (ECB).
As mentioned in our recent Lep Network newsletters, monitoring for black cutworm (BCW) and true armyworm (AMW) for this season has come to a close. However, an increase in BCW is being seen, with an average of 5.5 insects in Van Wert County.
For more resources on these pests and many others, check out our website: https://aginsects.osu.edu
Cajoling the Corn Earworm
This is our second week monitoring the corn earworm (CEW). 10 counties across Ohio monitored CEW populations, using 18 total bucket traps. In total, 16 average moths were reported. The highest amount of CEWs in one trap was 20, and the trap was in Auglaize County.
The corn earworm is a common corn pest found across Ohio that feeds on corn, tomato, and certain legume fields, which leads to feeding damage, molds, and an increased threat from birds. The adult moths are drawn to corn fields in the early green silk stage to lay their eggs. They can vary in color and the majority of feeding damage is found at the tips of the corn ears. For more information about CEW check out a previous newsletter: https://agcrops.osu.edu/newsletter/corn-newsletter/2019-27/corn-earworm-field-corn-watch-molds
Corn Earworm Moth Map
June 19 – June 25, 2023
Exploring the European Corn Borer
This is our sixth week monitoring the European corn borer with 2 IA variants and 0 NY variants being reported June 19th – June 25th. In total, 9 counties across Ohio are monitoring for both ECB variants, using 33 total wing traps. The 2 ECB-IA insects were captured in Hardin County.
The European Corn Borer (ECB) is a common corn pest in Ohio that readily prohibits proper flow of nutrients within an affected corn stalk. ECB exposes the host plant to various problems including stalk breakage, ear drop, and reduction in corn yield. ECB is more commonly a later season moth, so we plan to see an increase in population numbers for both ECB variants in the coming weeks. For more information about European corn borers, please visit: https://aginsects.osu.edu/sites/aginsects/files/imce/ENT_15_14.pdf
European Corn Borer (IA) Moth Map
June 19 – June 25, 2023
Welcoming the Western Bean Cutworm
This is our official first week of monitoring for Western bean cutworm (WBCW) adults in our 2023 season. 14 counties across Ohio monitored WBCW populations using 46 total bucket traps. Most of the counties had 0 moths reported, but 2 counties reported an average of 0.3 and 0.5 WBCWs, Hardin and Muskingum counties respectively.
The Western bean cutworm is a common pest in the northwest and west-central area of Ohio. WBCW adults tend to emerge from late June to early July, so we expect an increase in numbers continuing in the season. Adult WBCWs vary in dark brown and black coloring, with a white stripe along the outsides of the forewing, a light tan colored dot inward of the stripe, and behind the dot should be a tan-colored boomerang (or crescent) like mark.
Western Bean Cutworm Moth Map
June 19 – June 25, 2023
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Dates set for ODA Pesticide Collection across Ohio
REYNOLDSBURG, Ohio (May 3, 2023) – The Ohio Department of Agriculture (ODA) will be sponsoring three collection events for farmers wishing to dispose of unwanted pesticides. This year, the collections are happening in Morgan, Putnam, and Miami counties on the following days and locations:
- August 9, 9 a.m.–3 p.m.: Morgan County, Morgan County Fairgrounds, 2760 South Riverside Drive, McConnelsville, Ohio 43756
- August 10, 9 a.m.–3 p.m.: Putnam County, Putnam County Fairgrounds, Gate 5, 1206 East Second Street, Ottawa, Ohio 45856
- August 22, 9 a.m.–3 p.m.: Miami County, Miami County Fairgrounds, North Gate, 650 North County Road 25A, Troy, Ohio 45373
The pesticide collection and disposal services are free of charge, but only farm chemicals will be accepted. Paint, antifreeze, solvents, and household or non-farm pesticides will not be accepted.
The pesticide collections are sponsored by ODA in conjunction with the U.S. Environmental Protection Agency. To pre-register, or for more information, contact the Ohio Department of Agriculture at 614-728-6987.
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Drainage field day at Ohio State Lima campus farm scheduled for July 25
The Ohio State University at Lima will host a Drainage Installation Field Day on the campus farm on Tuesday, July 25, 2023.
Field demonstrations by the Ohio Land Improvement Contractors of America, or OLICA, will begin at 9 a.m. and will continue in an open-house-style format throughout the day. The event is free and open to the public. Parking will be available off Thayer Road. Maps of the campus with parking and registration areas marked are available as part of the registration process.
Lunch will be provided at noon. Bruce Clevenger, a farm management field specialist with OSU Extension, will make a short educational presentation about crop yields and the economic benefits of drainage and drainage water management. Space is limited for lunch, so RSVP by July 16. Register here or visit go.osu.edu/limadrainageday for more information.
Schedule
- 9 a.m.-noon: field demonstrations
- Noon-1:30 p.m.: lunch and educational presentation
- 1-3 p.m.: demonstrations continue in the field
The field day is brought to the area by The Ohio State University at Lima; Ohio State’s Department of Food, Agricultural and Biological Engineering; and OSU Extension, in cooperation with the Ohio Land Improvement Contractors Association, and OLICA Associate members.
The rain date is Tuesday, August 1, 2023.
Crop Observation and Recommendation Network
C.O.R.N. Newsletter is a summary of crop observations, related information, and appropriate recommendations for Ohio crop producers and industry. C.O.R.N. Newsletter is produced by the Ohio State University Extension Agronomy Team, state specialists at The Ohio State University and the Ohio Agricultural Research and Development Center (OARDC). C.O.R.N. Newsletter questions are directed to Extension and OARDC state specialists and associates at Ohio State.
Contributors
Disclaimer
The information presented here, along with any trade names used, is supplied with the understanding that no discrimination is intended and no endorsement is made by Ohio State University Extension is implied. Although every attempt is made to produce information that is complete, timely, and accurate, the pesticide user bears responsibility of consulting the pesticide label and adhering to those directions.
CFAES provides research and related educational programs to clientele on a nondiscriminatory basis. For an accessible format of this publication, visit cfaes.osu.edu/accessibility.