C.O.R.N. Newsletter: 2024-11
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Spring 2024 Weather & Soil Conditions: Update 4
Soil Temperatures and Moisture
Figure 1: Daily average air temperature (dashed red), two-inch (green) and four-inch (blue) soil temperatures for spring 2024. Soil type and location of measurements (under sod or bare soil) are provided in the lower right corner of each panel. A map of all locations is in the bottom right. Data provided by the College of Food, Agricultural, and Environmental Sciences (CFAES) Agricultural Research Stations located throughout the state.
Though daily average soil temperatures continued to climb most of last week, a late week cold front dropped two-inch and four-inch soil temperatures back down into the upper 40s to upper 50s (Figure 1).
It was yet another active week for severe weather, with five additional confirmed tornadoes (Champaign, Crawford, Delaware, Portage, and Trumbull Counties). This brings the state’s total to 35 in 2024, with peak season just beginning. Ohio normally sees about 20 tornadoes per year.
Figure 2: (Top) Precipitation (inches) for the 7-day period ending April 22, 2024 courtesy of the Advanced Hydrologic Prediction Service. (Bottom) Soil moisture percentile for 0-40cm depth as of Calculated soil moisture percentiles as of April 22, 2024, according to the NASA SPoRT-LIS product.
Rainfall was plentiful once again (Figure 2). Most of the state rceived 0.5-1.5”, with pockets over 2” in southern Hocking and northern Vinton Counties. Small creeks and streams flooded again, with high flows on all the major rivers. Soils remain saturated compared to late winter conditions (Figure 2). Cool conditions will continue early this week, but a warming trend over the weekend should bump soil temperatures up into the 50s to low 60s by early next week.
For more complete weather records for CFAES research stations, including temperature, precipitation, growing degree days, and other useful weather observations, please visit https://www.oardc.ohio-state.edu/weather1/.
Weather Forecast
We started Monday morning off chilly, with widespread frost across the state. A beautiful day on Monday has given way to more clouds and an increasing chance of rainshowers on Tuesday with cooler than average highs in the upper 50s to mid 60s. Showers should exit the state on Wednesday, with high pressure settling in and cooler highs in the upper 40s to low 60s (north to south). This will lead to another cold night Wednesday night into Thursday morning. Depending on clouds and location, frost is likely Thursday morning and some areas may fall off into the upper 20s to low 30s. We will see a warming trend beginning on Thursday, with 70s returning for Friday and Saturday. Southern Ohio may see highs in the low 80s by Sunday and Monday. However, scattered showers and storms will be possible Friday through Sunday. Overall, the Weather Prediction Center is currently forecasting 0.55-1.50” of precipitation over the next 7 days, with the heavier amounts across northwest Ohio (Figure 3).
Figure 3). Precipitation forecast from the Weather Prediction Center for 8pm Monday April 22 – 8pm Monday April 29, 2024.
The 6-10 day outlook from the Climate Prediction Center and the 16-Day Rainfall Outlook from NOAA/NWS/Ohio River Forecast Center show strong likelihood for above average temperatures with near to above average precipitation (Figure 4). Climate averages include a high-temperature range of 65-70°F, a low-temperature range of 43-48°F, and weekly total precipitation of 0.90-1.15”.
Figure 4) Climate Prediction Center 6-10 Day Outlook valid for April 28 - May 2, 2024, for left) temperatures and right) precipitation. Colors represent the probability of below, normal, or above normal conditions.
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Battle for the Belt: Season 2 Episode 4- Chilling Injury
Episode 4 of battle for the Belt is now available: https://www.youtube.com/watch?v=T5_QXF-Px7s
In Episode 4, Dr. Alex Lindsey, Associate Professor of Crop Ecophysiology & Agronomy, walks us through his current research project on how cold temperatures and water can affect early planted soybeans within the first 24 hours of planting.
How does cold temperature and water affect germination and emergence?
We have been studying how cold temperatures and water affect soybeans under ultra-early planting conditions using some lab experiments. We planted soybeans into field soil (starting at 20% or 60% available water content) at 1” (shallow) or 1.5” (normal) planting depths, and exposed them to different combinations of cold temperatures and water treatments during the first 24 hours after planting (Table 1). After the first 24 hours, we raised the temperature in the chamber to 70°F and measured emergence.
Table 1. Temperature and water treatments evaluated during the first 24 hrs after planting.
Preliminary results suggest that no water application (even if temperature dropped to 35°F) resulted in the greatest emergence (75%) after 11 days. Water application immediately after planting, regardless of whether it was 50°F or 35°F, cut the emergence totals in half. Application of ice after planting was less damaging to emergence but still reduced germination compared to where water wasn’t applied. This suggests that avoiding precipitation within the first 24 hours of planting is key to ensuring good emergence.
Does planting depth matter?
Interestingly, shallowly planted seeds (1-inch depth) had slightly lower emergence totals (10-15% less) compared to those planted at the normal depth of 1.5-inch when the soil was drier (20% available water content). The effect of planting depth on emergence was less noticeable when soils had 60% available water content at planting.
These results suggest it is possible that a 1.5-inch planting depth for ultra-early planting may result in better emergence than a shallower planting depth, but these results should be field tested before further recommendations can be made. Avoidance of precipitation of any sort in the first 24 hrs after planting was key to ensure best emergence with cold temperatures.
What is happening in the field?
The Western Agriculture Research Station is still the only location planted as much of the state has been water-saturated with little available suitable field work days since March 25th. However, southern Ohio last week was dry enough for planting in areas, so planting date 2 went in on April 16th (Table 1).
Planting date one (March 25) in both corn and soybeans have emerged! The high temperatures through last weekend helped to accumulate the required GDD for plant emergence (Table 2). The corn is between VE and V1 (first leaf collar) and the soybeans have the cotyledons coming through the soil (Figure 1). Temperatures were lower at this location the weekend of April 20th; cold injury will be scouted for this week.
Figure1: Corn and soybean on April 18 (planted on March 25) at the Western Agricultural Research Station in South Charleston, Ohio.
Table 1. The planting date conditions for planting date two at the Western Agricultural Research Station.
Location
Planting date
2-inch soil temperature
(at planting)Air Temperature
(at planting)
Western,
Clark County
April 16
64°F
84°F
Table 2. Weekly weather conditions for planting dates one and two at the Western location with day of planting, soil, air temperature averages, and Growing Degree Days (GDDS) from April 15 to April 21. Information from CFAES Weather System (https://weather.cfaes.osu.edu/).
Location
Precipitation
(Inches)
( April 15- April 21)
2-inch soil temperature
( April 15- April 21)Air Temperature
( April 15- April 21)
Planting date
GDDs
(Cumulative)
Western,
Clark County
0.13
Max: 68°F
Mean: 60°F
Minimum: 53°FMax: 85°F
Mean: 59°F
Minimum: 33°F
March 25th
April 16th
159
71
Additional Authors: Anu Neththasinghe Appuhamilage
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Statewide Alfalfa Weevil Population Update #1
Alfalfa weevil is a pest that develops and causes increasing levels of damage in alfalfa as growing degree days (GDD) accumulate. Most of southern Ohio is within the range of GDD for peak alfalfa weevil activity and as seen in the table below there is significant activity in northern countries that have not peaked yet.
The following table indicates the average alfalfa height and alfalfa weevil population for the couple of fields scouted in each county for the week of April 16th-22nd.
County
Alfalfa Height (inches)
Larvae Count per Stem
Allen
10-17
0.3
Defiance
6-10
0.1
Ross
8-16
1
All of the sample fields scouted this past week are below the threshold requiring a control method, with the southern Ohio sample fields in Ross County being the closest to that control threshold.
Alfalfa weevil scouting is very easy and helps guide decisions on harvest timing and insecticide usage, to maximize forage yield and quality. There are many great resources to get started, reference the article written earlier this year “Scouting Early Alfalfa Weevil Activity” and this forage team video “Alfalfa Weevil Scouting”. Alfalfa weevil control is determined by the average larvae per alfalfa stem and the maturity of the alfalfa stand. If control thresholds are met, options for control are an early harvest of insecticide usage. Both methods of control require timely decision making and the best way to do that is to know the levels of alfalfa weevil in your fields.
Additional Authors: Ryan Slaughter
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Lep Monitoring Network – Black Cutworm and True Armyworm
The Ohio Lep Monitoring Network has kicked off its third year of monitoring for Lepidopteran (moth/caterpillar) pests in agronomic crops. This year, we will be monitoring for black cutworm (BCW), true armyworm (AMW), corn earworm (CEW), and fall armyworm (FAW). In addition, a larger network of counties will report on Western bean cutworm (WBC) later in the season.
Our 2024 monitoring season has started off earlier than last year, with our first report of BCW and AMW moths from traps checked April 15th – 21st. To monitor for both BCW and AMW, wing traps with lures to attract the adults are deployed along the edge of fields and checked weekly (Figure 1).
Figure 1. A wing trap set up along a field edge. Separate traps are used to monitor BCW and AMW. Photo credit: Amy Raudenbush.
Black cutworm
Black cutworm is an early season agronomic pest. Adults are a brownish color and can be identified by a dagger shape on each forewing (Figure 2, circled in yellow). Adult moths are attracted to fields with broadleaf weeds, such as chickweed and purple dead nettle, where they lay eggs that then hatch and feed on developing plants.
Figure 2. Black cutworm moth with black, dagger shaped markings on the forewing (circled in yellow). Photo credit: Curtis Young.
Black cutworm is not able to overwinter in Ohio. The moths migrate from southern regions as temperatures begin to increase. Over the past week, we have had a mix of weather conditions in Ohio, including some warm temperatures, therefore, it is not surprising that some counties in Ohio have already started reporting BCW numbers.
During our first week, April 15th – 21st, we monitored 24 traps in 8 counties (Figure 3). Counties with the highest averages were Van Wert followed by Hardin (13.7 and 5.3 moths, respectively). Moths were not reported in three of the monitoring counties including: Auglaize, Pike and Wayne.
Counties with high trap numbers should plan to monitor BCW larvae after corn is planted, especially in fields with a lot of broadleaf weeds such broadleaf weeds, such as chickweed and purple dead nettle. For more information about BCW please visit: https://aginsects.osu.edu/sites/aginsects/files/imce/ENT_35_14 BCW.pdf
If BCW is a concern, and you are interested in reviewing corn varieties tolerant of BCW, please review the Handy Bt Trait Table: https://www.texasinsects.org/uploads/4/9/3/0/49304017/bttraittable_jan_2024.pdf
Black cutworm moth map
Week 1
April 15th to April 21st, 2024
Figure 3. Average black cutworm (BCW) moths captured from April 15th to 21st. The bold number on the left indicates the average moth count for the week, followed by the standard number on the right which indicates the total traps set up in that county.
True Armyworm
Similar to BCW, true armyworm (AMW) adults migrate to Ohio from southern regions in April and May. Adults are a light tan moth with a white dot on both wings (Figure 4). Moths are attracted to fields with grasses, winter wheat, barley, and rye cover crops, to lay their eggs.
Figure 4. True armyworm moth with white dot on wings (circled in yellow). Photo credit: Kylie Harbert.
Our first week of monitoring for AMW, April 15th – 21st, included 24 traps in 8 counties (Figure 5). Counties with the highest averages were Van Wert, and Auglaize counties (22.7 and 5 moths, respectively). Counties with high trap numbers should monitor for AMW larvae after corn is planted, especially in areas of grassy no-till fields or fields that had rye cover crop.
For corn varieties tolerant of AMW, please review the Handy Bt Trait Table: https://www.texasinsects.org/uploads/4/9/3/0/49304017/bttraittable_jan_2024.pdf
True Armyworm moth map
Week 1
April 15th to April 21st, 2024
Figure 5. Average true armyworm (AMW) moths captured from April 15th to April 21st. The bold number indicates the average moth count for the week, and the standard number in parentheses is the total number of traps set in that county.
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 more information, visit cfaesdiversity.osu.edu. For an accessible format of this publication, visit cfaes.osu.edu/accessibility.