Crop Update and Hail Damage: While I don’t remember numbers as well, calendar dates are something I tend to remember. And, in agriculture, there’s numerous dates that accumulate over one’s life from hail, tornado, blizzard, flood, and wind events. I was reflecting on the Aug. 6th hail storm that occurred in Merrick, York, and Seward counties in 2018. This past week on August 7th, some woke up to hail/wind damage in Adams, Clay, and Nuckolls counties. The tree damage was incredible. Michael Sindelar, Clay Co. Educator, and I surveyed damage a day later. My estimation of the worst hit crops: corn around 80% defoliation with varying percentages of greensnap above/below ear and soybeans around 50% defoliated/broken off/with at least 50% pods on the ground. Where hail stones hit the ears, the kernels are mushy and mold is already setting in on corn at milk stage. There’s also mold setting in on soybean pods hit with hail stones. It’s hard to receive crop damage any time. The good news is that nothing appears to be a total loss; the majority of what we looked at was less than 40% defoliated and in general, the hail did not seem to penetrate the stalks, thus early stalk rot doesn’t appear to be setting in. Pictures at https://jenreesources.com.
Tree Problems: The majority of my questions the past 10 days were regarding tree leaves turning yellow and dropping from trees. They look stark against green grass. In general, what’s happening is the fact that we’ve had high humidity for a period of time now and we’ve had rain throughout spring and summer. Fungal pathogens thrive in these conditions. So, ornamental/flowering pears have pear rust; crabapples and apples have scab and also cedar-apple rust (depending on varieties); maples, ash, sycamores are showing anthracnose; and a number of other fungal leaf spots are observable on shade trees in general. Evergreen trees show various fungal needle spots. Ultimately, we don’t recommend doing anything for these diseases this time of year. We typically don’t recommend to spray shade trees in general, but fruit and evergreen trees should be sprayed in the spring if fungal diseases have occurred in the past. So, fungal diseased leaves may drop early and you may or may not observe a new flush of leaves yet this year. These fungal diseases won’t kill deciduous trees. They can kill evergreen trees over a period of years.
Oak leaves turning brown in clusters was also observed this past week. Sometimes
browning of leaves can be due to a fungal disease called anthracnose. Most of what I’m seeing, I believe, is environmental. It could be due to changes in hot/cool and periods of heavy moisture followed by lack of moisture on trees that had a huge flush of leaves due to moisture this spring. I really don’t know the cause for sure, but it doesn’t appear to be disease related from what I can tell. We wouldn’t recommend doing anything for the trees at this time.
UBBNRD Public Hearing: The Upper Big Blue NRD will hold a public hearing and informational open house on Aug. 19 at 7:00 p.m. at the Holthus Convention Center. The purpose is to receive comments on proposed changes to District Rule 5 – Ground Water Management Area Rules and Regulations. A complete copy of Rule 5 and the proposed changes are available at the district office and at www.upperbigblue.org/publichearing. The public will have the opportunity to learn more about these proposed changes and their effects, and address NRD board members about their concerns or support.
The proposed changes would stipulate that an approved nitrification inhibitor must be applied at the manufacturer’s recommended rate with pre-plant nitrogen fertilizer in the following situations: The application of anhydrous ammonia prior to March 1; The application of all nitrogen fertilizers other than anhydrous ammonia after February 29. In addition to these requirements, in Phase II and Phase III areas pre-plant application of nitrogen fertilizer shall not exceed 120 lbs. per acre. The remaining nitrogen fertilizer may be applied post plant. Prior to applying nitrogen fertilizer, but no later than April 1 of each year, each operator in the management area will be required to report information regarding the use of best management practices. For more information, visit www.upperbigblue.org or call (402)362-6601.
York County Corn Grower Plot Tour will be held Aug. 20th from 5-7 p.m. at 1611 Rd. 14 east of York. Pizza and refreshments will be provided and check out the latest hybrids. Guess the winning yield without going over and win a $50 gas card. All are welcome!
*End of News Column. Hail damage photos below.
Prevent Planting and Herbicides for Cover Crops: This past week, corn for silage was approved as a cover crop in prevent plant situations, primarily because of the herbicide restrictions on cover crops for forage. A team of us wrote an article about how to understand herbicide rotation restrictions and also shared the information from NRCS regarding corn as a cover crop in this week’s CropWatch. You can see these and more articles about soybean gall midge and Japanese beetles at http://cropwatch.unl.edu.
Hail Damage: For a ‘slight chance’ of rain, it was interesting to have the hail and 4” of rain in the gauge Wednesday morning! It appears we had hail from the York area through Cordova area and I heard there was also hail in Butler and Platte counties. The larger hail appeared to have damaged crops into Kansas through Superior, south and west of Lawrence through Blue Hill and Holstein. What was encouraging was not even 24 hours after the storm, signs of recovery could be seen in corn and soybean. Warm temps, no rain, and sunshine make all the difference in recovery after hail compared to cool, wet, cloudy conditions. I went back to look at fields in the southern tier of counties into Kansas and in York area southeast on Friday and was further encouraged by the regrowth. You can view photos on my blog at https://jenreesources.com. The bruising on stalks and stems can allow stalk rot to set in on corn and soybean stems to become brittle and break off with wind…so keep this in mind towards harvest and plan to get these fields out first if possible. What’s hardest is wheat fields that were nearing harvest that shattered or were totaled due to hail. Also difficult is the fact we’ve lost so much canopy in crops at the peak of palmer growth for those who have fields with palmer problems. And speaking of palmer, a reminder of the palmer amaranth field day near Carleton on July 10th. View herbicide options for palmer control and listen to keynote speaker Dr. Jason Norsworthy from the University of Arkansas. Registration at: http://agronomy.unl.edu/palmer.
So, this may sound crazy, but I was curious about the potential of interseeding a cover in these corn fields with extreme canopy missing right now. I was standing in one field of V11-12 corn with all the leaves gone listening to the growers tell me how much of a palmer problem this field has, even though it is clean right now. We know from research that interseeding at this growth stage typically doesn’t work due to canopy closure, but I’m wondering if it could help with weed pressure since the remaining leaves may be more upright and may not completely shade the rows? The keys to this consideration would be the herbicides used and considering rotation restrictions if you plan on using the stalks and cover for forage after harvest. If you don’t plan to use the cover for forage, there wouldn’t be restrictions as you’d assume planting at your own risk. We can’t predict if it will keep raining for non-irrigated fields. It would also be wise to talk with your crop insurance agent about this.
Fungicides in Hail Damaged Crops: Several have asked about fungicide use on hail damaged crops. There’s no good research to support this and fungicides only control fungal diseases. Bacterial diseases such as bacterial leaf streak and Goss’ wilt are favored after hail events. We’ve already seen both of these diseases in this part of the State due to heavy rains. Fungicides at some point may help with stalk strength with all the bruising and we may need fungicides later this season for disease if the humidity and rains continue.
The available research had fungicides applied at tassel instead of the earlier growth stages we’re currently at. ISU did a one-year 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 yield increase in 12 of the 20 fields). A study was also conducted by Carl Bradley at the University of Illinois in 2007-2008 to evaluate the effects of fungicide applications at tassel in simulated hail-injured corn on gray leaf spot severity and yield. In that study, fungicide applications did not statistically increase yield when applied on corn that was damaged to simulate hail injury.
If you’re considering a fungicide now, you could consider an on-farm research study depending on equipment, ability to get in the field, and crop height. Spray fungicide in enough width to complete 2 combine passes. Then skip an area for 2 combine passes. Then treat again and repeat across the field. View: Fungicide Protocol for Hailed Corn and Soybean. Some talking about this wondered about aerial applications. If we had enough people who left a check, we could look at combining the data to make up for lack of reps in one field. Please let me know if you’re interested in either of these options.
Butterflies and Soybean Defoliators: Painted lady butterflies and others like sulfur butterflies can be seen flying around as they’re emerging from soybean fields. I really wish they’d move on but I’m seeing butterflies in my gardens now too, so we’re just going to have to keep scouting fields. There’s also a lot of yellow striped armyworms out there of various larval stages. If your soybeans don’t seem to be growing or you seem to be losing canopy beyond hail damage and ‘burner’ herbicides, be looking for various larvae. In this heat, if you have a lot of residue in the field, they may be hiding under it, so be sure to look there too if you have a spot in the field especially affected.
NOTE: End of News Column. Photos below to document recovery.
Soybeans with new growth seen in axillary buds and/or main shoot within 24 hours of June 26 hail storm (first two photos) and 3 days after hail storm (last two photos). Soybeans were V4 to R1. Note, temperatures were hot with sun and dry conditions post-hail.
Wheat grain shelled from heads and broken heads in both early and later planted wheat. Warm season forages may be a good option to consider in totaled out wheat fields.
First photo is corn west of Lawrence on July 26 and showing regrowth in second photo 3 days later. Third photo is corn near York on July 26 showing growth in whorl not damaged. Last photo is worst hail damaged area I saw near Webber, KS. There was nothing left of soybean in the nearby fields.
Hail damage on stems may be only on the outer surface of leaves with no bruising below that (as in first two photos). Or, it can be more severe where bruising is leading to rot setting into the stem (as in last two photos).
This post shares observations of what I’ve been seeing in fields pre-harvest and during harvest during this 2018 growing season. Some of these problems stemmed from hail/wind damage and others insect damage. This is a longer post with the desire to have many resources available to you in one place. Hopefully this will be helpful for diagnosing concerns as harvest continues.
(Photos above) Hail-damaged soybeans pre-harvest. The plants in this field weren’t pummeled into the ground, but from the road it was deceiving as to what the soybeans were actually like on these plants. The two smaller photos are all the soybeans found on 2 adjacent plants from the top soybean photo pre-harvest. There were a lot of aborted pods on stems and moldy beans in general. For those who combined hail damaged beans in the area, farmers shared they had everything from ‘lima’ beans to shriveled, moldy beans as you can see in these pics, which is also what we were anticipating may be found.
Cladosporium ear and kernel rot seen on kernels already affected by Fusarium, particularly in hail damaged fields. This is a lesser ear rot fungi and doesn’t produce a mycotoxin but can create increased damage to kernels. Was recommending taking grain damaged to this extent directly to the elevator.
Photos above shared by a Clay County farmer who observed kernel germination and Fusarium growth (mostly due to western bean cutworm damage) upon harvesting his field. Hormonal balance within the kernels shifts towards harvest. At full maturity, very little abscisic acid (ABA) is left in the kernel (in both corn and soybeans) which allows them to germinate in correct conditions after harvest. These conditions include moisture and temperatures above 50ºF. Presence of fungi such as Fusarium and Gibberella also increases gibberellins in the kernels allowing for kernel germination with presence of moisture as we’re seeing this harvest. Increasing air flow during harvest will hopefully blow most of these damaged kernels out the back of the combine.
- Corn Ear Rots, Storage Molds, Mycotoxins, and Animal Health, ISU, 1997. (Nice comprehensive resource available in PDF download via web search)
- UNL Corn Disease Profile III: Ear Rots
There’s over 25 species of fungi that can produce ear molds with the majority of them ceasing growth at 15% moisture within the kernel. Thus, we recommend drying grain to 15% moisture as quickly as possible to cease additional fungal growth within the grain bin. The table below shares the days required to dry corn to 15% moisture with 1.0 cfm/bu and various temperature and humidity conditions.
- Management of in-bin natural air grain drying systems to minimize energy cost
- Grain storage management to reduce mold and mycotoxins (ppt presentation)
- UNL CropWatch Grain Storage Resources
- Managing large grain bins for potential mycotoxin contamination
In 2018, we’re primarily seeing Fusarium and Gibberella species which have the potential to produce mycotoxins. Thus, the information below is directed at those fungal species and mycotoxin levels that can be associated with them. Again, the presence of fungi does not automatically mean a mycotoxin is present.
- Grain storage management to reduce mold and mycotoxins (ppt presentation)
- UNL CropWatch Grain Storage Resources
- Managing large grain bins for potential mycotoxin contamination
- Understanding Fungal Toxins UNL
- Sampling and Analyzing Feed for Toxins UNL
- Use of Feed Contaminated with Fungal Toxins UNL
- Feeding Storm Damaged Corn: A few thoughts from a Veterinarian
Also, there’s a new app called “Mycotoxins” and it’s another resource with ear rot pictures and mycotoxin information put out by several Universities produced for both Apple and Android devices.
Hail Damage Info: Thank you to all who attended our hail damage meetings last Monday and we truly hope the information was helpful. It was a lot of information at one time, so I have compiled it at: https://jenreesources.com/2018/08/14/late-season-hail-damage-resources/.
The ‘blessing’ in the timing of these later-season storms is in the reduced kernel moisture and shorter length of time till harvest. This is important to reduce the time for fungal growth in the ears. If you missed the meeting, presentations and information are at the link above. The main key I will stress: Please, ask your crop insurance agent how he/she wants to handle grain quality at harvest. Does the agent want to take samples for mold/potential mycotoxin? Does the agent go off of COOP samples? Does the agent require samples prior to going in the bin? These are key questions as we do know there is fungal growth on damaged ears. The presence of fungal growth does not automatically mean the presence of a mycotoxin. However, if grain quality isn’t handled and documented correctly at harvest, it can mean the loss of compensation if grain goes out of quality in storage. If anyone is taking hail damaged corn for silage, Dr. Mary Drewnoski is interested in samples prior to and after ensiling and is willing to help with sample analysis cost. Even if silage has already occurred, we’d be interested in samples after ensiling. Please contact me if interested. I will share additional considerations next week, but please check out the weblink above (or if it’s easier just go to http://jenreesources.com). Please let me know if you have any questions!
York County Corn Grower Plot Tailgate will be held from 5-7 p.m. on August 23rd. The plot is located east of York on Road 14 between Roads O and P on the north side of the road. View hybrids and visit with company representatives. Also, provide your estimate of the highest yield of the plot without going over. The winner will be awarded a Yeti cooler at the York County Corn Grower banquet in November. Pizza and beverages will be provided. Hope to see you there!
South Central Ag Lab Field Day will be held Wednesday, Aug. 29 from 8:55 a.m. to 4 p.m. at 851 HWY 6 near Harvard, NE. The day will begin with registration at 8:30 a.m., followed by tours of research sites through 4 p.m. Keynote speaker for the lunch is Mike Boehm, University of Nebraska-Lincoln Harlan Vice Chancellor for the Institute of Agriculture and Natural Resources and University of Nebraska vice president. Participants will be able to choose from four of the following six tours during the day. View program brochure for schedule.
Topics include the latest research in: Cover crops to corn issues; Corn insect management; Comparisons of variable rate irrigation and fertigation to fixed rate and impacts of cover crops on soil quality; Nitrogen fertilizer management (inhibitors and sensors) in irrigated corn; Corn and soybean disease updates; and Opportunities and challenges for weed control in soybean. CCA credits have been applied for. To register, please go to: https://go.unl.edu/2018scalfieldday by Aug. 26 for lunch planning purposes. Directions: 13 miles east of Hastings on Hwy 6 or 4.5 miles west of the intersection of Hwy 14 and Hwy 6. north of Clay Center.
Hamilton County Corn Grower Plot Tour will be held August 29th beginning at 11 a.m. The field location is just west of M Road and Hwy 34 on the south side (4 miles west of the Hwy 34 and 14 junction in Aurora), just past the viaduct. The program will feature Tom Hoegemeyer talking about the history of corn and how plant breeders have improved the yields. Kelly Brunkhorst, Executive Director of the Nebraska Corn Board will round out the program with an update on trade, the farm bill, and tariffs. Lunch starts at noon at the Oswald Farm followed by the featured speakers. The farm is located from L Road and Hwy 34 (5 miles west of the Hwy 34 and 14 junction in Aurora), 1 mile south to 12th Rd., then 1/2 mile west on the south side of the road.
Irrigation Field Days: Field days on Aug. 27 and 28 will demonstrate soil water measuring tools in production fields designed to help growers feel confident with their irrigation scheduling decisions. The demonstrations will show several irrigation scheduling equipment systems that were installed in the field this summer and have been recording data. Field Days will be located:
- August 27 – near Broken Bow. The August 27 presentation will be part of the Custer County Corn Growers 2018 Field Day at the Jeremy Coleman farm near Broken Bow. The tour will start at 5:30 p.m. at the field site, located five miles west of the intersection of Hwy 2 and Callaway Road then south ¾ mile on 433 Road. A meal will be served about 6:30 p.m. at Coleman’s shop one mile east of the field on Road 798. The educational program will be presented during the meal.
- August 28 – near Bradshaw. The August 28 tour will start at 12 p.m. with field demonstrations of the irrigation scheduling equipment, followed by a meal and presentations in the farm shop. The Bruce Hudson farm is at 2405 Road G, Bradshaw. That is 3.5 miles east of Polk on Hwy 66 to Rd G and 2 .7 miles south or from Benedict (Hwy 81 & State Spur 93C) 6 miles west to Rd G and 2.25 miles north.
A special thank you to the Nebraska Extension team who shared during today’s hail damage meetings! They were well attended with nearly 120 participants between the two locations. Hopefully the information was of help as you talk with your crop insurance adjuster and know what to expect going forward. Below are the resources we provided and additional items including presentations that were discussed. Contact information for the speakers is listed at the bottom of this post. We will continue to add resources to this page if you’d like to check back. Thanks!
- Dr. Justin McMechan’s Presentation: Corn and Soybeans Hail Panel 2018
- Jenny Rees Presentation: StormDamageDiscussion-8-13-18
- Steve Melvin Irrigation Information: Irrigation Scheduling for Hail Damaged Crops
General Hail Damage Resources:
UNL Extension Hail Know web site: https://cropwatch.unl.edu/hailknow
Hail Damage Videos:
- Hail Damage Evaluation and Management in Soybeans
- Hail Damage Evaluation and Management in Corn
- Weed Management Considerations Following Hail
UNL CropWatch Storm Damage: https://cropwatch.unl.edu/storm-damage-response-information
Corn at Beginning Dent needs 5” of water; ¼ milk = 3.75”; ½ milk (Full dent) = 2.25”; ¾ milk = 1”. Soybean at beginning seed (R5) = 6.5”; R6 full seed = 3.5”; leaves beginning to yellow = 1.9”.
NebGuide Predicting the Last Irrigation of the Season. Use the last page to walk through an example of how much water you may need to finish out the crop for crop insurance purposes. Also realize that severely hail damaged plants may progress more rapidly than the number of days for each growth stage listed in this NebGuide and that damaged plants may not use as much water as mentioned here. http://extensionpublications.unl.edu/assets/pdf/g1871.pdf
Crop coefficients chart by growth stage: https://nawmn.unl.edu/GrowthStageData
If anyone is taking hail damaged corn for silage, Dr. Mary Drewnoski is interested in samples prior to and after ensiling and is willing to help with sample analysis cost. Even if silage has already occurred, we’d be interested in samples after ensiling. Please contact her if interested (contact info. at bottom of this post).
The three links below are the ones that answer specific questions. The first article answers a few questions regarding forage considerations for hail-damaged corn and soybean. The over-riding decisions will be based on planting date. Sudangrass or sorghum x sudangrass crosses and millets are still appropriate until August 15, although seed supplies of these are dwindling. After that, we are looking at oats/turnips. Drilling these directly into the stubble is the best option for planting. There was also a great discussion regarding earlage and we need to create an article regarding that topic.
This article addresses nitrate concerns when grazing forage cover crops: https://cropwatch.unl.edu/2018/reducing-nitrate-concerns-when-grazing-forage-cover-crops
This article addresses cover crops:
|COVER CROP||USE/GOAL||WHEN TO PLANT||HOW TO SEED||RATE
|OATS||Weed Management||By Sept. 1||Drill best. Can fly on.||30-40 lbs||*|
|OATS/RYE MIX||Weed Management||By Sept. 1||Drill best. Can fly on.||30 lbs each||*|
|OATS||Forage||By Sept. 1||Drill best. Can fly on.||80-90 lbs||*|
|OAT/RYE MIX||Forage||By Sept. 1||Drill best. Can fly on.||30-40 lbs of rye and 50-60 lbs oats||*|
|BRASSICAS (TURNIP, COLLARD, RAPESEED)-NOT OILSEED RADISHES||Cover ground, forage, nitrogen uptake||By Sept. 1||Fly on for quicker establishment.||5-6 lbs||—|
|RYE||Weed management, cover ground, forage, nitrogen uptake||After Sept. 1||Drill best. Can fly on.||50-60 lbs||*|
|*If adding a brassica to any of these small grain options, only 2 lb/ac is needed. Rapeseed isn’t as well known, but is an inexpensive and good option for consideration.|
Other Forage Considerations
- Earlage: For fields where the ear is now the top-most plant portion, silage is not a good option, but earlage can be. This resource from North Dakota State University, Harvesting, Storing and Feeding corn as Earlage, provides good information on earlage.
- Grazing: Whenever possible, attempting to harvest the corn first would be best. It’s not a good idea to graze the corn with ears on the stalks. A better option would be to harvest the corn and graze afterward, following considerations that we used for the downed corn situation in 2017. See Down Corn: Problem or Opportunity for Cattle Producers?
- Silage: The following are good silage resources — Silage Considerations (UNL BeefWatch) and videos from the Silage for Beef Cattle Conference.
Grain Quality/Mold/Mycotoxins/Grain Storage:
Diplodia ear rot is perhaps the most common with these types of storms. Good news, Diplodia does not have a mycotoxin associated with it. Bad news is this fungus explodes on an ear creating light-weight ears and explodes in grain bins.
It will be wise to assess which fields/portions of fields are affected the worst with mold. Consider not storing any of that grain as it will be difficult to manage and keep from getting worse in storage. You will also need to assess which fields have increased risk of stalk rot by using the pinch test (Use your thumb and first finger to pinch the stalk internode above the soil line. If it easily crushes, the plant has stalk rot). Consider harvesting those portions of fields or fields most affected by stalk rot first.
Ear Rot Diseases and Grain Molds: http://extensionpublications.unl.edu/assets/pdf/ec1901.pdf
Stalk Rot Diseases: http://extensionpublications.unl.edu/assets/pdf/ec1868.pdf
Sprouting of Corn Kernels: https://cropwatch.unl.edu/sprouting-corn-kernels-hail-damaged-ears
Tips for Testing Storm Damaged Corn (Veterinarian perspective): https://cropwatch.unl.edu/storm-damaged-corn-tips-testing-and-using
Grain Storage Resources: https://cropwatch.unl.edu/grain-storage-management
Crop Insurance Questions:
Every field situation may vary. If you have hail insurance, the insurance adjuster should evaluate ear damage in addition to percent defoliation and stalk breakage.
Ask your insurance adjuster how they assess grain quality damage.
- What are their rules?
- Do they go by the COOP results for mold/mycotoxin/dockage?
- Do they require the insurance agent to come out and take a sample for mold/mycotoxin?
- Do they require you to call them before you put grain into your bin? (This is especially the case if aflatoxin may be of concern. We don’t anticipate that being a problem with this storm damage. However, if they require a sample for mold/mycotoxin in general, they may ask you to call them to take a sample before the grain gets put into a bin).
- If you do have presence of mold and/or mycotoxin, it’s best to have it documented before the grain goes into the bin. If the grain gets out of quality and the mold and/or mycotoxin increases in your bin by spring, if it wasn’t documented at harvest, you may not get compensated.
Mary Drewnoski Daren Redfearn Justin McMechan
Extension Beef Nutritionist Extension Forage Specialist Extension Crop Systems
402-472-6289 (402) 472-2662 (402) 624-8041
firstname.lastname@example.org email@example.com firstname.lastname@example.org
Crop Update: I’m so sorry to all affected by Monday night’s hail/wind storms! For those reading this before Monday, a reminder of hail damage meetings we’re having Monday Morning, 10 a.m. at the Utica Auditorium and Monday Afternoon, 1:30 p.m. at the Fairgrounds in Central City. I will post key points of what’s discussed at http://jenreesources.com after the meetings. Please also check out our Hail Know Website at https://cropwatch.unl.edu/hailknow and take the survey on the page to help us better know how to serve you with that resource.
This week’s CropWatch at http://cropwatch.unl.edu shares two different dicamba-related articles. One is a case study to walk through the forensic analysis for off-target dicamba movement showing how it originated from a corn field. The other goes into more detail regarding soybean still producing a new node every 3.7 days upon off-target dicamba movement (as long as the apical meristem has not been killed). It’s truly a significant piece of information, because without it, the assumptions within the forensic analysis don’t work!
Also, you have an opportunity to share your voice and input. This past week we’ve heard that EPA is planning to make their decision by mid-August on whether or not to extend registrations of XtendiMax®, Engenia®, and FeXapan® in order to help inform the seed and chemical industry for next year’s purchases. Some of you have called or talked with me about this. A few have understandably been pretty upset that these products are getting so much blame when, in this part of the State, much off-target dicamba movement starts from corn applications. That doesn’t get as much press nationally. While I’ve tried hard to share the story here and am grateful to our media partners who have helped me, I’m one very small voice. I have no idea what will happen; my concern is the bigger picture-potentially losing dicamba period as a tool in our toolbox.
So you have an opportunity to share your voice in Nebraska Extension’s survey that will be shared with the EPA: https://www.surveymonkey.com/r/JWDCY3C. Share your opinion on Xtend technology. Share your opinion on where you’ve discovered off-target movement from in 2017 and 2018. Share your opinion on dicamba. The results will also be compiled and shared on CropWatch and winter meetings. Thank you for considering this!
Aphids and Frogeye: I’ve also received a handful of questions regarding corn leaf aphids in corn and frogeye leaf spot in soybean. Both have rapidly increased in some corn and soybean fields. At beginning dent and various stages of starch-fill corn, I just have a hard time putting anything else into this crop. So I haven’t been recommending insecticides and there’s no thresholds this late to support it. In fields I checked from last week to this week with corn leaf and bird cherry oat aphids, I’ve also seen an explosion of beneficial insects and mummification occurring of aphids, which is helpful. Regarding frogeye, it’s one where we recommend a product containing a high amount of strobilurin at R3 or R5. Many beans are at R6 or almost there, so again, I’m having a hard time putting any more money into this. High humidity and leaf wetness for 12 hours or more will rapidly increase frogeye, so the worst situations I’ve seen through the years are in gravity-irrigated fields. Also, seeing a number of soybean defoliators in fields. Please check out this CropWatch article at: https://cropwatch.unl.edu/2018/soybean-defoliators to better help understand how much defoliation can occur in soybean.
Lawn Renovation: For those seeking to improve your lawn or get one established, August is a great time to do so! I really like this resource for this purpose: https://go.unl.edu/rz9z. If you’d prefer to watch videos, Backyard Farmer has a series of Lawn Renovation videos, but this link gets you to the most recent one regarding fall renovation: https://youtu.be/Fxd1NUQ8ScQ.
Crop Update: What a blessing to have rain this past week! Grateful for how it provided much needed moisture into the top two feet in many cases. Updated soil moisture status will be at http://jenreesources.com. Some in our area and in other parts of the State received wind, hail damage, and flooding to crops. This week’s CropWatch at http://cropwatch.unl.edu shares information for those situations. A few summarizing points: for those with greensnap or with severe hail damage, you may wonder what potential yield may be based on your planting date and current plant stand. The following chart from Iowa State University and explanation of how to understand it may be helpful: https://crops.extension.iastate.edu/cropnews/2009/05/assessing-corn-stands-replanting.
For those with flooding, corn in the V7-10 leaf stage can survive for about 7-10 days in flooded water. Temperatures above 86F can result in greater stress on those plants than if the temps remain cooler than that during that time. Another consideration for the future, it’s not uncommon to find a disease called ‘crazy top’ of corn when the tassels begin to emerge. We’ve seen this the past several years where creeks or areas along waterways or field edges were ponded. There’s nothing you can do to prevent this.
For those with hail damage, damage from V7-10 leaf corn can result in a number of situations depending on the severity of hail. Minimal yield loss is assumed for leaf damage in crop insurance charts. Final plant stands will be important which will account for broken off plants that don’t recover. Stem bruising also isn’t factored in. For corn, bacterial diseases tend to be my larger concern at these growth stages. Bacterial top rot is one in which the plant dies from the top down and has a strong odor to it and creates a soft, slimy mess. Goss’ wilt is another concern-particularly systemic Goss’ wilt. You can check for this if you have a dying plant that doesn’t have a soft rot by taking a
cross section of the stem and looking for discoloration of the vascular bundles. You can also send plants like this to the Plant and Pest Diagnostic Lab in Lincoln for confirmation.
Regarding fungicide use on hail damaged corn, Iowa State and the University of Illinois did studies finding similar results. Both found no statistical difference in applying a fungicide vs. the untreated check in spite of small numerical differences. Regarding timing, the Iowa State study simulated hail damage at tassel and applied fungicide an average of 3 days and 8 days post-hail. There were no statistical differences on yield of the timing of the applications either. They did find statistically less fungal diseases in the hail-damaged plots vs. the non-hail damaged plots and speculated it was due to more air flow and less leaf area available for disease to occur. I have observed that fungicide can help with stalk strength and maintaining whatever green tissue remains when we had the 2013 hail storm in Clay County at brown-silk to blister corn. But this early, it’s hard to justify a fungicide application based on the data that’s available. If you’re interested in testing this for yourself, the following is an on-farm research Fungicide Protocol for Hailed Corn and Soybean.
For hail damage on soybean, many of the beans are at flowering or approaching flowering. Again, stem bruising isn’t counted in crop insurance assessments. I haven’t really observed bacterial or other disease issues necessarily from stem bruising in soybean. What tends to be more of an issue is those plants hardening off and becoming brittle to walk through. For soybeans, the blessing is that often new buds form and you will see increased branching which can help with canopy closure…it just can hurt right now when soybeans were already near canopy and we’re trying to reduce additional inputs for weed control. Things to consider are that pods may be closer to the ground from this increased branching and you may need to harvest earlier to help with getting beans that become brittle before snapping off in wind storms. I leave plant stands of near 60,000 plants/acre based on our soybean pop studies that received hail damage. If you want to prove any replanting differences to yourself, you may wish to consider the following Soybean Replant Protocol. We’d recommend waiting on herbicide apps till some new growth occurs, which is difficult when I’ve watched palmer essentially be not affected by hail and put on two new leaves within a few days in the past. Last year we started making herbicide apps 5-7 days post-hail. Additional hail resources are at a new resource called ‘Hail Know’ at: https://cropwatch.unl.edu/hailknow. There’s a lot of info I haven’t transferred to this site yet…but you can view photos and comments on hail recovery at numerous growth stages over time at my blog under the ‘Storm Damage’ category: https://jenreesources.com/category/storm-damage-2/.
Last week I shared the following video regarding determining timing of off-target dicamba movement to soybean: https://youtu.be/rQid7-vX-TU. Sharing again with an increase in the number of fields that were experiencing cupped symptoms last week.
This year I was counting my blessings as we made it through May with no tornadoes in Clay County and no Memorial Day storms! Yet history seems to repeat itself on days. Last year, hail went through the counties north of us on June 3. This year, hail hit us on June 3rd….an estimated 30% of Clay County. Please also see the resources listed at the end of this post for more specific information regarding decision-making.
For more information on hail and replant decisions, please see:
On August 1, 2013, a severe wind and hail storm damaged 170,000 acres of corn and 86,000 acres of soybeans in Clay County, Nebraska. Corn at the time of the storm was from brown silk-blister. While the storms in the Gibbon/Blue Hill areas occurred a little earlier in the growing season, the following photos show the progression of damage in the event it can be of help to those affected by 2014 storms.