Hail Damage Assessment
There’s been a lot of hail damage this past week in Nebraska. It’s always so hard to see the damage, regardless of when the storms come. I’m sorry for those impacted and am grateful for safety as many lost windows in homes too. Various tools are available to show hail storm paths. I grabbed these from ‘Interactive Hail Maps’ to get a better feel for how much of Nebraska has been impacted this week (June 5, 6, 7, 9 2022 shown below).
We are at a critical time right now for making replant decisions with the federal crop replant date next Tuesday. Have looked at a lot of fields the past few days with a range of damages. The following is what I’m doing in assessments right now that I’ve found to be practical for me in the event it can help you. Will also share some tools, what to watch for, and some thoughts based on questions received.
- HailKnow Website (has 6 sections including assessing damage): https://cropwatch.unl.edu/hailknow
- Webpage: https://cropwatch.unl.edu/hail-know/assess-my-damage
- Infographic: https://cropwatch.unl.edu/Hail/Images/HailKnow-Damage-Assessment.png
- Assessment Video: https://cropwatch.unl.edu/hail-know/video-hail-damage-assessment
- 2014 Storm Recovery Information: https://cropwatch.unl.edu/2014-storm-recovery-information
- Corn Hybrid Maturities & Late Planting: https://go.unl.edu/gnas
- Strategies with Late Soy Planting: https://go.unl.edu/20ry
- Corn GDD Tool: https://hprcc.unl.edu/agroclimate/gdd.php
- Bean Cam Replant App: https://ipcm.wisc.edu/apps/beancam/
What to Do Now
- Look at fields to see damage extent. Know what growth stage the field was in at time of the storm.
- Call crop insurance.
- Call an agronomist or review resources to anticipate what to look for in plant recovery.
- Flag plants in the field to assess recovery. This greatly aids in learning and has helped me tremendously! Taking a picture now and a week later of the same plants also helps.
- Wait 5-7 days to assess recovery. I realize the waiting is perhaps the hardest when we’re up against deadlines, but we need time to see what will happen with plant recovery.
- Consider options on what to do if the crop is totaled or not including herbicides applied, crop rotation restrictions, marketing and crop insurance, weed control going forward, etc.
Growth Staging Corn
It’s important to know the growth stage at the time of the storm. You may have an idea on the growth stage from crop scouting reports. You can also do this yourself by finding the tallest plant standing in an area and dig it up. What I describe here is the agronomic method of counting collars and nodes which is different from the leaf method that crop insurance will use. Slice open the plant to view the growing point. Every leaf on a corn plant is attached to a node. There’s 4 nodes where the first 4 leaves attach in a triangle at the base of the plant. Then there’s a small gap and you will see a line that marks node 5 followed by a larger gap and a line that marks node 6. Because of the cooler soil temps this year, I’m finding smaller gaps between nodes 4 to 5 and 5 to 6 (nodes are closer together). Pulling collard leaves back, they will snap off at whichever nodes they are attached to (which can help you in determining the more advanced growth stages from 6 to 8 leaves). We had plants that ranged from emergence to V8 from what I’ve seen thus far. We say the growing point doesn’t come above ground till typically V5-V6. For corn that was less than V6 and cut off to stumps or at ground level, there’s potential for it to come back. I actually was seeing new growth today (2 days post-hail) on plants that were cut off at ground level. However, I will also say that’s not a guarantee as it all depends on how bacterial rots set in.
Stand Assessments for Corn
Next I take stand assessments by counting 1/1000th of an acre. I actually feel corn plants at the base as I count to see if they feel firm (likely to survive) or mushy (not likely) and only count plants which appear most likely to survive. I also keep track of which ones are questionable. In the previous paragraph I mentioned slicing a plant open to find the growing point. For these assessments, I use my finger to measure on that plant where the growing point is. Then for the stumps that are in a row, I use my finger to measure each stump of a plant to get a feel if the growing point may be above or below what’s left of the stump. If questionable, I don’t count it. It’s not perfect since slicing open the plant is always best, but it provides an idea for right now anyway. Some plants have quite a bit of hail damage to stems and we will have to see how far the damage penetrates for stalk rot. There’s some fields from the road that I didn’t think looked that bad until I got in them and realized how many were wrapped or where they were cut off. I’ve gotten between 15-26K for stands thus far with usually 3-6 questionable plants that weren’t counted. There are some fields that were near completely cut off below the growing point.
What to expect for corn
I know we’re tired of wind, but wind and sun are helpful right now. Today was so much better assessing plants as the wind has helped senesce dead parts of plants and started the process of tearing off bent whorls so the new growth can push through. For bent whorls that remain bent and don’t slough off, the new growth stays wrapped and those plants won’t survive. Watch stumps for new growth (depending on where the growing point may have been). Also watch stumps in particular to see if bacterial rot sets in. Even though the growing point is below ground, I’m unsure about some of the V2-V4 corn that was snapped off by washing rain and debris as to whether or not those plants will come back due to rot setting in. I just don’t know and that’s why we wait.
You can flag plants and also open up a few plants with hail damaged stems to see how deeply the stones penetrated the stalk tissue. I was seeing bacterial stalk rot already setting in today (2 days post-hail), which isn’t good, but something to be aware of. I’m also seeing discolored crowns at base of plants in some fields when they’re split open. Unsure why that is but ultimately, what’s more critical is that the growing point of the plant is healthy (white/cream color and firm, not brown and mushy).
What to expect for soybean
I haven’t taken any stand counts for soybean. I’ve only seen maybe two fields that may need replant at this point (from my perspective). Soybeans are so incredible at compensating! Today was seeing 3-5 growing points emerging on some of these sticks. They key to survival is if the plant was cut above or below the cotyledons. What I’m seeing for farmers who planted soybeans April 19-25, the cotyledons are close to the ground because of the cooler soil temps, which is good because there’s growing points lower on the sticks of stems that are left. In a week, these beans will look a lot different. I know people want to write them off now, but it’s incredible what they will do with some sunshine and 7-10 days. However, in saying that, each field is a field by field assessment. UNL and University of Wisconsin recommend leaving stands of 50,000 plants/ac. The bigger issue I realize at this point is weed control since early beans were V4-V5 and bushing nicely prior to this storm. Check out this cool app from University of Wisconsin on replanting bean decisions: Bean Cam Soybean Replant App.
Regarding herbicide applied and crop replant, ultimately, view the label for any replant and/or rotation restrictions (or 2022 Weed Guide starting on page 198). And, it’s good to have conversations with area chemical reps for specific questions on what may or may not be safe to try.
The corn replant decision is hard. It’s obviously an economical one, but there’s various slants to consider on it, especially in regards to crop insurance and how much a crop has been marketed. Each field will need to be assessed. I know some are hoping for crop insurance to total fields, but I really don’t know if they will total stands of 15-20K plants or not. Again, these are field by field decisions. If the field is totaled, depending on herbicides, replanting to corn, milo, and soybean may be options. A few have been interested in forages and that is really a conversation about your goals and how the forage will be harvested.
For those wanting to plant corn, we can’t predict when a fall frost will occur each year. What we can do is look at historical trends to get an idea on maturities to plant for different dates that hopefully will mature prior to frost. The following is based on data at: https://hprcc.unl.edu/agroclimate/gdd.php. For those located in a different part of the State, select your location on the map at the above web link. Then input the planting date and relative maturity you’re considering and see where it aligns with the 28F historical frost date. Below are charts I created for York and Clay Counties. Additional information on corn hybrid maturities and late planting can be found here: https://go.unl.edu/gnas.
|York Ne Data|
Avg. 28F frost Oct. 21
|Planting Date||GDD to R6||1917||2038||2159||2280||2401||2521||2642|
|June 15||Sept. 5||Sept. 11||Sept. 19||Sept. 28||Oct. 8||Oct. 23***||***|
|June 20||Sept. 11||Sept. 18||Sept. 27||Oct. 7||Oct. 22***||***||***|
|June 25||Sept. 18||Sept. 27||Oct. 7||Oct. 21||***||***||***|
|June 30||Sept. 27||Oct. 7||Oct. 21||***||***||***||***|
|***Date is beyond average 28F frost event of Oct. 21|
***indicates the date is beyond the average 28F average first frost of October 21.
|Clay Center, Ne Data|
Avg. 28F frost Oct. 18
|Planting Date||GDD to R6||1917||2038||2159||2280||2401||2521||2642|
|June 15||Sept. 9||Sept. 16||Sept. 25||Oct. 5||Oct. 20***||***||***|
|June 20||Sept. 15||Sept. 24||Oct. 4||Oct. 17||***||***||***|
|June 25||Sept. 23||Oct. 3||Oct. 16||***||***||***||***|
|June 30||Oct. 2||Oct. 15||***||***||***||***||***|
|***Date is beyond average 28F frost event of Oct. 18|
***indicates the date is beyond the average 28F average first frost of October 18.
If changing from corn to soybean in the replant decision, maybe it’d be wise to poke some soybeans in the ground now just to see how they fare with the herbicide that’s been applied? And maybe you try poking them in at different depths? I know I normally recommend planting deeper, but right now I’m suggesting shallower…like 1″…to hopefully be above any herbicide band that moved into the soil (if planting into a corn field) and to hopefully get the beans out of the ground quicker. The following article shares considerations for soybean when planting mid-June: https://go.unl.edu/20ry. In summary of it, for maturities, UNL recommends to stick with as similar maturity as possible till around June 15 and then consider switching to 0.5-1.0 maturity group less. I’m hearing from many seed dealers that beans are in short supply, so talk with your seed rep if you’re thinking about seeding beans at this point. Different thoughts on row spacing. Drilling or 15″ can close canopy sooner but we saw problems with white mold last year in the area and 30″ also allows for cultivation as a weed control option with application date restrictions on herbicide-tolerant bean traits. Wider rows should hopefully close canopy unless the beans get hit with off-target herbicide. Seeding rates are also debated. Many sources recommend to increase them by 10% after early June. I can appreciate the thought behind that and honestly don’t have a preference either way. In my experience with seeding rates, I didn’t see a difference in canopy closure timing with 90K to 180K, but my experiences have been with early April-May plantings.
There’s also a number of thoughts regarding products. We don’t have research on the nutrient side for those asking about applying various products. I do feel sulfur has some healing properties but have no research to share.
Regarding fungicides, we don’t recommend them from the standpoint that hail doesn’t create fungal diseases. At some point, they could be helpful to aid in stalk strength. However, if you’re considering this in the next few weeks, consider proving it to yourselves with on-farm research this year so we do have data for the future. All you do is spray fungicide in enough width so two 2 combine passes can be obtained. Then skip an area for at least 2 combine passes. Then treat again and repeat across the field. Fungicide Protocol for Hailed Corn and Soybean. Please let me know if you’re interested in this!
Timing of fungicide app: ISU did a study to simulate hail damaged corn at tassel stage within an average of 3 or 8 days post-hail. They didn’t find the timing to provide any yield effects. They also didn’t find a statistical yield increase (90% confidence level) in fungicide application to hail damaged plants vs those which weren’t hailed although they also reported a numerical increase in 12 of the 20 fields. They also interestingly found that hail damaged crops had less foliar disease than non-hail damaged crops in their 3 year simulated hail-damage study.
For herbicide application, some labels recommend waiting 2-3 days after a crop damage event. Ultimately, to be on the safe side, it would be wise to wait for new regrowth on both the crop and the weeds.
Hopefully some of this helps as you assess your hail damage situation. It can be emotionally draining to look at all the damage, but would encourage you to look for all the small positives you can find. Getting away to enjoy a hobby, talking to another person, relying on one’s faith, and keeping a greater perspective helps. We do have resources at our Rural Wellness website at: https://ruralwellness.unl.edu/. Hang in there and wishing you the best with your decisions! Please reach out with any questions or additional information.