Late Season Hail Damage Resources

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!

Presentations:

General Hail Damage Resources:

UNL Extension Hail Know web site: https://cropwatch.unl.edu/hailknow

  • Dr. Justin McMechan’s video explaining what crop insurance looks for regarding hail damage (will be posted soon)

UNL CropWatch Storm Damage: https://cropwatch.unl.edu/storm-damage-response-information

Irrigation:

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

Forages:

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.

https://cropwatch.unl.edu/2018/forage-cover-crop-considerations-after-hail-corn-and-soybean

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:
https://cropwatch.unl.edu/2018/cover-crops-soil-health-storm-damaged-fields

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
mary.drewnoski@unl.edu         dredfearn2@unl.edu                   justin.mcmechan@unl.edu

Steve Melvin                                 Jenny Rees
Extension Educator                    Extension Educator
(308) 946-3843                             (402) 440-4739
steve.melvin@unl.edu               jrees2@unl.edu

JenREES 8-12-18

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.

Hail Damage Meetings

Aug. 13 Hail Damage Meeting

JenREES 8-5-18

Thank you to all who made the York County Fair go so smoothly! It’s always a joy to see the 4-H and FFA youth and families rewarded for the hard work they put into their projects!

Crop Update: I didn’t get out to the field much this week with fair but did spend a few

IMAG5589

Bird cherry oat aphids on ear husks and green leaf aphids on leaves of plants in this non-irrigated field. Lady beetle larvae predators also present.

hours one afternoon. There are portions of the area I serve that have been blessed with rains and look really good. The main thing that I’m seeing a lot more of this week is aphids in corn fields. This can be common in fields where fungicide is applied as the fungicide kills a beneficial fungus that attacks aphids. Some aphid species are also attracted to moisture stressed crops. The heat has also pushed the crop along quickly. We have another yield forecasting article in this week’s CropWatch at http://cropwatch.unl.edu where we talk about the impact of the heat on yields. As of right now, based on comparing this year to 30 years of weather data, it’s appearing corn may reach maturity 1-3 weeks early. Irrigated yields are estimated to be near average and above to near average for non-irrigated corn (where drought is not a factor).  These yield forecasts are based on simulations under ‘perfect conditions’ (with no nutrient loss, disease etc.) but they can give us an indication of what may happen if we continue with higher heat conditions.

 

Unfortunately, pockets in the area continue to miss rains. The drought monitor still is not

IMAG5559

Drought-stressed soybean field.

reflecting the drought in this part of the State; at this point, I’m unsure what else either Al Dutcher or I can do about this. One farmer reminded me drought occurred in the same area in 2006, 2012, and now 2018-six years apart each time. Driving the area, hardest drought-stressed crops really took a turn this past week with corn in hard dough to early dent with some kernel abortion and soybeans are beginning to abort pods and quit filling seeds. One question has been on weighing taking corn for silage or not. If you have at least an estimated 50 bu/ac grain in most of the field other than highly compacted areas, it may be more profitable to keep for grain (unless you’re looking for cattle feed). The following are some resources to consider further:

Dicamba: We’ve often mentioned the research showing a soybean plant producing a new node every 3.7 days upon reaching V1 stage. And, I’ve used that in the forensics assessment for determining a timing for off-target dicamba movement. One question I’ve had was “Do soybean plants continue to produce a new node every 3.7 days upon being affected by off-target dicamba?” My assumption in the forensic analysis I have used is that a new node continued to be produced every 3.7 days in spite of off-target dicamba. However, the only way to really test this would be to have the same soybean variety in both an Xtend and non-Xtend version. We will release a CropWatch article next week in which a situation like this occurred at the Eastern NE Research and Extension Center. Dr. Jim Specht counted nodes in both the non-Xtend variety with off-target dicamba and the Xtend variety that wasn’t affected. He found the same number of nodes in spite of the dicamba affected non-Xtend variety being shorter in height and having less canopy. So that in itself is good information for use in forensic assessments. However, he also found plants in which a higher off-target dicamba dose affected the top-most growing point. When that occurred, the number of nodes was affected.

Last year, a group of us released a dicamba survey during Soybean Management Field Days. Reminder those are upcoming this week (https://enre.unl.edu/soydays)! The survey helps us understand your perspectives about dicamba and this year we’ve added questions regarding using Xtend technology. Hopefully it will provide helpful information for all of us and the results will be shared via CropWatch and winter meetings.  We’d encourage and be grateful for any soybean growers to participate at: https://www.surveymonkey.com/r/JWDCY3C.

South Central Ag Lab Field Day: Please hold August 29, 2018 for UNL’s South Central Ag Lab (SCAL) Field Day near Clay Center! Attendees can choose which sessions you would like to attend. Options include the latest SCAL research in the areas of Irrigation/Water Use; Nutrient Management; Weed, Disease, and Insect Management; Cover Crops; and Cropping Systems. CCA credits will be available and there’s no charge to attend. Will have more specifics for you next week but please hold the date for now!

Vine Crop Problems: The following resource explains options for diagnosing various problems with cucumbers, squash, and melons: https://hortnews.extension.iastate.edu/2011/8-24/cucurbitwilt.html.

 

JenREES 7-28-18

Crop Update: By the time you read this I truly hope and pray we’ve received some rain for the entire area who receive this! Al Dutcher and I have been somewhat frustrated regarding the drought monitor reacting to short-term precipitation events over long-term trends. We both spoke at a meeting this week where he shared parts of this area have 6-8″ deficits dating back to the beginning of our water year (October 1). The soil moisture sensor ground-truthing I’ve been doing with area farmers shows that the larger rains only helped the top two feet of the profile and rains have been spotty since. I think the driest portion of the area seems to be from Lawrence to Bladen south. Drought monitor did put a portion of our area back into ‘abnormally dry’ again and you can see the updated soil moisture readings for the region at http://jenreesources.com.

We were blessed with cooler temperatures which helped slow the crop progression. The heat was pushing crops along quickly which can negatively impact yields as we discussed in a recent CropWatch article. The cooler temps with humidity and leaf wetness also favored gray leaf spot, though, and I’ve seen it move up to a leaf below the ear in several fields in several counties this past week. Every field situation may differ so it’s important to check your specific fields.

Soybean Management Field Days: It’s hard to believe but this is the 20th year of Soybean Management Field Days! They will be held August 7-10 at four locations across the State beginning with 9 a.m. registration and concluding at 2:30 p.m.:

Kenesaw — Tuesday, Aug. 7, Dean Jacobitz Farm
Albion — Wednesday, Aug. 8, John and Mike Frey Farm
Hartington — Thursday, Aug. 9, Ed Lammers Farm
Cedar Bluffs — Friday, Aug. 10, Ray Jr. and Kevin Kucera

The field days are sponsored by the Nebraska Soybean Checkoff in partnership with Nebraska Extension in the University of Nebraska–Lincoln’s Institute of Agriculture and Natural Resources, and are funded through soybean checkoff dollars. The efforts of the checkoff are directed by the United Soybean Board promoting progress powered by U.S. farmers. For more information about the field days and maps to sites, visit enre.unl.edu/soydays. Presenters include university specialists, educators and industry consultants. Topics include:
  • Marketing, Risk Management and Farm Policy
  • Weed Management: Cover Crops and Weed Control, Conventional vs. Traited, Soybean Variety Production
  • Cover Crops: Managing Soybean Insects and Pathogens
  • Cover Crops and Soybean Production Irrigation Management, Soil Fertility, and Cover Crop Research

Horticulture Update: It’s been a tough year for garden produce! The heat has affected flower set, pollination, and fruit production on many types of plants. I’ve also received many questions about tomato leaves curling. Leaf curling can be due to many things such as water stress, virus, and herbicides. Much of what I’m seeing now is water stress-related where uneven watering is occurring or because of the amount of leaves present (especially on heirloom plants) and the plant’s inability to keep up with transpiration. Have also received questions on bumpy tomato stems. The ‘bumps’ are actually adventitious roots (also known as tomato stem primordia) where if they touch the soil they’d form roots. Above ground, they are just these bumps and are present when we have high humidity or overwatering. These conditions are also being favored by the heavier one-time rain events that have been received during the growing season this year.

Squash vine borers causing tunneling in crown and vines of zucchini plants.

Also lots of questions this week regarding cucumber, squash, and melon vines dying! There’s a number of potential culprits. Most affected zucchini (including mine) and pumpkins contain squash vine borers. The female moth lays eggs at the base of plants where the eggs will hatch and the caterpillars will bore into the stem. The borer is white or cream colored with a brown head and can get to be 1″ long. They tend to prefer squash over melons and cucumbers. So what can you do now? Kathleen Cue, Extension Educator in Dodge County shares “If plants look good but holes in the stem indicate infestation, a knife can be used to cut with the grain of the stalk to find the borers. Use the point of the knife to pierce them and don’t be surprised if more than one borer is found in a stem. Once the borers are removed, cover the cut area with soil to encourage new roots higher up on the stem. Champion pumpkin growers will place soil over many nodes (the place where leaves emerge from the stem) along the length of vines to encourage lots of rooting. This gives plants greater resiliency if the squash vine borer has destroyed the crown of the plant.” So, if you’re still desiring more squash and pumpkins, that’s one option for you. If your plants are completely destroyed, you can just remove all the dead material to remove any actively feeding caterpillars as well. For next year, make sure to rotate the area where you plant your vine crops. Area master gardeners have shared they put aluminum foil around the stem base of vine crops to keep the borer larvae from penetrating the vines. Another option is to apply insecticides like carbaryl or permethrin around the base of stems. Trapping the adults in June by using yellow-colored containers filled with water can provide an indication when the moths are flying. You can then use floating row covers over the plants to prevent egg laying and remove them once flowering begins to allow pollination to occur. I will discuss other vine crop problems next week.

Reminder of York County Fair this week!

Soil Moisture 7-26-18

The drought monitor put a portion of our area back into ‘abnormally dry’. Soil moisture sensors in non-irrigated ground suggest portions of our area should be listed at least in D1 drought status. I got creative in posting these as I had to take pictures with my phone of the pics I created on the computer…so if they’re a little grainy, that’s why. Here’s the updated readings for the area!

On Wed. July 25, this area received 1.7″ one mile south of where the sensors are located and 1.49″ one mile east of it . Corn in this field is at soft dough stage.

This location only received 0.24″ and is very dry with soil moisture depletion above 50% for all four feet. The soybeans in this field are beginning seed.

This location also received only 0.24″ of rain. The corn in the field is showing drought stress and soil moisture depletion is above 50% for the profile.

The top foot at this location is steadily drying out with total soil moisture depletion around 35%. Corn is at milk stage.

This location received 1.15″ of rain on Wed. July 25. Total soil moisture depletion is above 50% and the field really started showing drought stress the past week.

The soybeans in this field are at R5 and total soil moisture depletion is approaching 50% depletion.

JenREES 7-22-18

Crop Update: This past week was fairly interesting with southern rust being confirmed in a few Fillmore, Thayer, and Saunders County fields.  We would recommend to continue scouting fields as the disease was low incidence at all these sites. There also were a number of questions regarding fungicide applications.

For those asking about chemigating fungicides, it’s important to ensure the fungicide

On-farm chemigation

On-Farm Research design for those considering chemigation vs. none of fungicide (could also use this for 2 different irrigation amounts instead). Can have more pies than this for smaller area if desired-we would just need at least 4-5 pies of each of same area. Data can be collected throughout field normally during harvest via yield monitor and we can use software to determine yields within the pies as long as we know the angle degrees you used.

product label allows for chemigation and to follow the recommended irrigation amount if specified on the label. If an irrigation amount isn’t specified, Tamra Jackson-Ziems and I were talking about trying to apply with as small amount as possible (perhaps like 0.25″). She has chemigation data at 0.25″ vs. 0.50″ vs. ground application from 2005-2007, but not vs. aerial application. The data had a high degree of variability numerically in the yield data in spite of non-statistical differences. The only other info I could find was the University of Georgia recommends only 0.10″ on chemigation using fungicides, but they didn’t show any data. I encourage those who can to please consider doing this as an on-farm research study where chemigation occurs in pies throughout the field with other pies left untreated. I realize it’s not popular to leave areas untreated, but it may be of interest to you.  For those asking about comparing aerial vs. chemigation for corn, that would be very difficult with one pivot with true research involving replication. Perhaps it could be done if a producer had a couple of quarters side by side, planted the same day with same hybrid and crop rotation where we could truly compare via research. If you do and that’s of interest to you, please contact either Tamra or myself. A couple have also discussed maybe applying half a pivot aerially and the other half via chemigation and just taking observations, which may also be beneficial to you.

We also released a few CropWatch articles this week on differentiating growth regulator herbicide injury in soybean and using a forensic method to diagnose off-target dicamba

dicamba injury-Purdue

Dicamba on Soybean: Because dicamba negatively affects leaflet margin cell division, direct dicamba exposure to nearly fully developed leaflets results in in a “draw-string” injury symptom at the leaflet tips, thus shortening the leaflet length. Keep in mind, however, that the translocation of dicamba from directly exposed leaflets to very young leaf primordia developing at new nodes at the main stem apex will also induce leaf cupping in those yet to emerge leaflets, even though these very young leaflet primordia were not directly exposed to dicamba. The same can be true for new trifoliolates occurring from additional stem branching at lower nodes. Photo via Purdue University.

injury in soybean. Please check them out at http://cropwatch.unl.edu. I hadn’t heard anyone really explain the difference between 2,4-D and dicamba in how they work in plants so felt that information was important in addition to the fact dicamba is highly translocateable and 2,4-D isn’t. That also has been important in home-owner discussions regarding off-target movement to garden produce. And, a reminder to all home-owners that weed control products used in lawns and empty lots often contain dicamba and/or 2,4-D…so it’s important to read those labels regarding environmental conditions in applying them and also when you can/can’t use grass clippings as mulch.

Buzzing Beetles: This past week, several people came to the office or called

2-4D injury Purdue

2,4-D on Soybean: 2,4-D impacts cell division in the more central (major vascular) portion of the leaflet. Low-dose 2,4-D exposure induces injury that results in a “narrowed, strap-shaped” leaflet in which the leaflet veins are made more parallel. This 2,4-D-induced injury is often accompanied by a rugose leaf surface ― a botanical term describing a rough leaf surface of irregularly spaced bumps/wrinkles and prominent ridged/corrugated leaf veins. Low-dose 2,4-D exposure will also lessen leaflet area, but differently, by narrowing/elongating the leaflet. 2,4-D is also not highly translocatable, wheras dicamba is. Photo via Purdue University.

regarding large green beetles flying around that sounded like bumble bees. These are called Green June beetles. They only fly during the day. There are also smaller green beetles with white spots (tufts of hair) around the abdomen; those are Japanese beetles. Japanese beetles feed on crops in addition to favorites such as Linden trees and knockout roses.  Both have larval forms that are white grubs and both have a one year life cycle. In the beetle form, both adult beetles are fond of ripe fruit such as grapes, berries, plums, and peaches. As larvae, the grubs feed on decaying organic matter and grass roots in the soil. However, the June beetle larvae can reach 2″ long creating larger tunnels in lawns and pastures as they move in the soil.

Some have said, “I thought June beetles were golden/tan!” And you would be correct! There’s several types of “June” beetles. The most common and perhaps most damaging is known as the June beetle or masked chafer which is golden/tan in color and has a one year life cycle. There’s also a May/June beetle (also known as the 3 year grub) which tends to do more damage in range/pasture ground. Those beetles are tan to brown/near black in color.

When it comes to damage, start looking for browning areas of turf occurring late July, throughout August, and early September. The turf may look like drought stress or fungal disease; however, if you can gently roll the turf back like a carpet, it’s most likely grubs (and you should also find the presence of grubs). Other signs of grubs can include birds, skunks, etc. tearing up your lawn. White grubs in general feed on decaying organic matter, lawn and ornamental roots in the soil. Grubs don’t tend to be an issue in fescue lawns or lawns that are low maintenance or newly established. They tend to prefer Kentucky bluegrass lawns that are highly maintained with fertilizer and irrigation. They also may be spotty in their feeding such as under yard lights or on irrigated slopes. The threshold level for turfgrass damage by masked chafer larvae is 8-10 white grubs per square foot of lawn…so I would assume that to be the case for all grub species. One or two grubs per square foot is normal and does not require control. If grub control is needed, products like Sevin or Dylox provide the best control for mature grubs and should be watered in after application.

JenREES 7-15-18

Crop Updates: A great deal of timely information was provided in this week’s CropWatch at http://cropwatch.unl.edu including information about high heat and pollination, applying fertilizer during pollination, western bean cutworm scouting, forecasted yields, etc. Please check it out!

Several called me asking about applying fertilizer during pollination. I shared that while

IMAG5438

I wasn’t aware of research, I personally was concerned about anything potentially interfering with pollination and that I do recommend 30 lbs of N at brown silk if needed or if you were originally planning split nitrogen apps. This is based on research from Purdue sharing today’s hybrids use 30-40% of their total Nitrogen from flowering through maturity. After discussing with Dr. Tom Hoegemeyer, Adjunct UNL Professor of Practice, he offered the following insights: “Pollination mostly occurs between 8:30 a.m. and Noon. Thus, as a precaution, I would not run a pivot on pollinating corn from 6 a.m. to Noon. When the temperature is 90°F to 95°F, the pollen is killed by heat and is seldom viable past 2 p.m. That leaves lots of time to run pivots, apply N, etc. when it won’t harm pollination. Silks tend to be viable for three or four days at these temperatures, so if a plant isn’t pollinated one day, generally the next day will work just fine. (If nitrogen is needed), I’d recommend that nitrogen go on as soon as practical. Corn nitrogen use is very high during the pre-tassel growth phase and again at kernel growth, from one to three weeks post pollination. About seven to ten days post pollination (before brown silk) lower N will start causing kernel abortion and serious yield loss in corn.” The UNL recommendation for fertigation is to use 30 lb of N with 0.25″ of water or 50-60 lb of N with 0.50″ of water.

Last week also brought questions regarding thresholds and difficulty in finding Western Bean Cutworm egg masses with moth flights at their peak. You can view light trap data from UNL’s South Central Ag Lab thanks to Terry Devries at: https://scal.unl.edu/ltr2018.pdf. There’s also a great article in this week’s CropWatch on how to scout for them, insecticide options, and additional recommendations. Thresholds for western bean cutworm are 5-8% of corn plants in the field containing egg masses or larvae. Egg masses can be difficult to find during pollination with pollen hiding them. ‘Typically’ egg masses are found in the top third of the plant on the upper sides of leaves and near midribs or leaf axils. However, with higher heat, I tend to find them closer to the ears and have even seen masses laid on the ear husks and on the backsides of leaves (not common). While larvae are generally known to move up the plant to feed at the tassels, I’ve seen high heat force larvae into ears earlier. It typically takes 5-7 days for larvae to hatch and the egg masses turn purple just prior to hatching. A number of insecticide options are available for both aerial application and via chemigation; these products are listed in the CropWatch article.

With insecticide applications occurring in corn for both western bean cutworm and also corn rootworm beetles, many have also called or talked with me about the recommendation of fungicide applications. Right now, I haven’t found gray leaf spot above 3 leaves below the ear leaf in several counties. There’s been some mis-diagnosing bacterial leaf streak as gray leaf spot. Southern rust was just confirmed in a Kansas county this week, but we still have yet to confirm it in Nebraska. Even the longest residual products won’t get us through August if a fungicide application occurs now. I can appreciate that economics are tight so the thought is to save an additional application cost by applying a fungicide now with the insecticide. And, I can appreciate economics are tight regarding why apply a fungicide right now when disease pressure doesn’t warrant it? Perhaps, at least those of you with the ability to chemigate could consider waiting till disease pressure warrants it for your field, if it does. Always in the back of my mind is the need for late-season protection with southern rust eventually showing up and gray leaf spot often worse then.

My perspective is from a resistance management and research-based one. We have 5 total modes of action for fungicides with 2 of them being in nearly every fungicide product we use in corn, soybean, and wheat because they work against foliar fungal pathogens. At some point, our pathogens will also adapt, as we’ve seen our weeds and insects do…it would be like losing our ability to control gray leaf spot and southern rust similar to palmer amaranth on the weed side. In Nebraska, Dr. Tamra Jackson-Ziem’s research has not shown an automatic yield increase to fungicide application in the absence of disease. And, it has also not shown an automatic yield increase when applied at tassel. In a high heat and low disease year like 2012, there were no statistical yield differences with fungicide application vs. the untreated control. Even in years with some disease pressure such as 2008-2010, she found no statistical yield differences between when various products were applied from Tassel through Dough stages. In high disease years, her research shows the benefit of fungicide application for reduced disease pressure and increased stalk strength. Fungicides are great tools to help us with disease pressure and stalk strength. Just would encourage all of us to consider when we really need to apply them and to understand that research in Nebraska does not automatically show increased yields with the use of them or with the timing of Tassel/Silking vs. later in the year. Also, hybrids may vary in their response due to disease susceptibility and other factors. Not all her data is listed at this site, but you can view it for yourself at: https://go.unl.edu/ni3y.

Bagworms: I’ve been seeing shelter belts and various trees turning brown from heavy

18 bagworm on Meridian Aborvitae K Feehan 7 9 18

Severe bagworm infestation on arborvitae. Photo via Kelly Feehan, Extension Educator Platte Co.

bagworm infestations. Please be checking your trees if you are noticing them turning brown. Additional information can be found at: https://go.unl.edu/rgju.

Soil Moisture 7-11-18

drought monitor 7-10-18

Drought monitor as of 7-9-18.  From the moisture graphs below, I don’t agree that at least portions of Nuckolls and Thayer counties were removed from drought status and other portions of our region no longer show abnormally dry.  Even though we were blessed with some large rain events, the moisture really helped only the top two feet of the profile since in areas of this region, the soil moisture status had never fully recharged at the 3 and 4 foot levels.  I did not provide graphs last week for groundtruthing as I took a few days off over July 4th.  We will see how or if this is adjusted in the future.

Byron 7-11-18

This location received 1″ prior to 6/29 since the last graph and ? on July ? Total soil moisture depletion for this location (top 4 feet) is around 30% depletion based on this graph.  The third foot is actually hard and dry compared to how wet it showed the past several weeks on these graphs, so I’m unsure if there’s an old root or earthworm channel that’s been keeping the sensor reading wetter than what I actually probe.  But it is now drying back out in this graph.  Corn at this location is pollinating.

Superior 7-11-18

Total rains received since the last graph are ? Total soil moisture depletion (top 4 feet) is at 50%.  Corn at this location was three leaves from tasseling on 7/11.

Lawrence 7-11-18 Corn

Since the last graph, this location has received ? of rain.  Total soil moisture depletion (top four feet) in this field is at 50% depletion.  Soybean at this location is nearing beginning pod.

Lawrence 7-11-18 Soy

Rains received since the last time I showed graphs are ? Total soil moisture depletion (top three feet) is showing above 50% depletion.  Corn at this location is pollinating.

Clay Center 7-11-18

This location has received some rains and current total soil moisture is around field capacity for this field.  Corn is pollinating at this location.

Seward 7-11-18

This location has been blessed with rains.  It wasn’t difficult to install these sensors and the total depletion (currently showing top three feet) around 30% depletion.  I hadn’t hooked up the fourth foot sensor yet, thus why no readings are shown this week for it.  Corn is pollinating at this location.

York 7-11-18

This location received 4.5″ of rain on ? which helped with the top two feet of the profile.  An additional ? was received on July 1.  Since then, no significant rainfall has been received at this location with the soil moisture depletion (four feet total) around 35%.  Soybean is at beginning pod at this location.

JenREES 7-8-18

Crop Update:  A few diseases started showing up the past few weeks in various portions of eastern and south central Nebraska.  Phytophthora root rot in soybean is perhaps the

imag532977190165.jpg

Phytophthora root and stem rot in soybean. Notice wilted plant with leaves hanging on turning yellow/brown.  Also notice characteristic brown lesion from base of plant up a good six inches on this plant.  This affected plant is surrounded by healthy plants.

most common in both areas.  We normally think of this disease as seedling damping off and death; however, it can also affect plants later in the season.  What surprised me was how much we are seeing it this year in higher ground and sidehills instead of the typical lower ground we often see it on.  Dr. Loren Giesler, Extension Soybean Pathologist said that in situations where we’ve had dry conditions followed by heavy rains (as we have this year), especially on clayey or soils prone to compaction, Phytophthora can also affect plants.  He has a few videos along with additional information at the following website:  https://go.unl.edu/tdfh.  Symptoms characteristic at these growth stages include wilting of plants during the day with leaves eventually turning yellow-brown-gray and remaining on the plants.  Also, look for a brown stem lesion that goes from the soil line upward about 4-6″.  Some of these plants are also snapping off at the soil line. For those experiencing Phytophthora this year, future management includes:

  • Using resistant varieties including a combination of good partial resistance and an Rps gene. Partial resistance alone will not be as effective during early growth stages or under high disease pressure.
  • Cultural practices include anything that can improve soil drainage and compaction.
  • Seed treatment fungicides containing mefenoxam or metalaxyl should be used and you may need to consider a higher rate of them.

Regarding corn diseases, bacterial leaf streak (BLS) has greatly increased on more

bacterial leaf streak

Bacterial Leaf Streak (BLS) in corn.  Lesions are elongated and skinny staying between the leaf veins, similar to gray leaf spot (gls).  However, leaf margins are wavy and diagnostics under the microscope show the presence of bacterial streaming from the leaf veins.  With gray leaf spot, there will be the presence of fungal spores.  Thus, the importance of correct diagnosis when considering fungicide applications.

susceptible hybrids since rain events.  Early lesions can look very similar to gray leaf spot, so it’s important to correctly identify the two.  The margins of BLS are wavy vs. those of gray leaf spot are more blunt.  Both can have yellow margins when backlit by the sun.  Fungicides are not effective against BLS and hybrids do vary in their tolerance to this disease.  It’s important to scout fields as we may see an increase in fungal diseases due to the humidity, leaf wetness, and recent rain events.  Southern rust has taken awhile to develop in the southern U.S., which is somewhat unusual, yet many states have been in drought this year too.  As of July 5th, southern rust has been confirmed in Georgia with one suspected sample in a Missouri county.  You can watch the map at: http://ext.ipipe.org/ and follow @corndisease on Twitter for the latest on corn disease findings in the U.S.

Trees:  With numerous wind storms, the following resource has a lot of great information regarding pruning storm damaged trees correctly and questions to ask tree care services regarding tree pruning:  https://go.unl.edu/94fm.

Agronomy Youth Field Day:  All youth ages 9-18 years old are invited to the 3rd Annual Agronomy Youth Field Day. Youth will have exciting educational experiences while discovering Science & Agronomy/ Irrigation / Mechanized Agricultural careers for producing Nebraska crops! The field day will be held Wednesday, August 8 from 9 a.m.-3 p.m. at Nebraska College of Technical Agriculture Educational Center in Curtis, NE.

Hands-on activities (for all age levels) will focus on pest management, equipment technology, crop growth, soil management, precision farming & center-pivot irrigation technology. Several Nebraska Extension Cropping & Water Systems and 4-H Youth Development Educators along with Nebraska College of Technical Agriculture in Curtis Agronomy / Ag Mechanics Department professors will be sharing the researched based information with the students.

Participants will gain important life skills while discovering the science behind producing Nebraska crops. The six-hour field day is a great opportunity for ALL the youth to learn more about the agronomy industry and increase their basic understanding of science, ag literacy, a technology & STEM while exploring careers. Parents/Adults are welcome and lunch will be provided.

Reserve your spot today by registering online at:  https://go.unl.edu/agronomyyouthfieldday  by August 3, 2018. For more information (or if trouble with registration) contact Nebraska Extension Frontier County at 308-367-4424 or email 4-H Educator Kathy Burr at kathy.burr@unl.edu.

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