Category Archives: JenREES Columns
JenREES 6-10-18
Thank you to Tena with Faller Landscape in York and to all the youth who participated in our 4-H landscape design workshop and helped plant the Nebraska area! It will hopefully be beautiful for fair!
Crop Update: Rain continues to be spotty and windstorms have resulted in various levels of greensnap in some fields. Overall crops are growing and getting a decent canopy. It’s been interesting watching the radar on weather apps as so often they look like precipitation should be occurring yet that’s not always the case. Grateful for all of you who share crop updates-including things such as impacts on hay crops, pastures, etc. and for our farmers working with me on soil moisture monitoring. I was told this past week of the impact of our groundtruthing on the drought monitor; radar would make it appear we’re not as dry as we truly are. So just wanted to share that with you-that your input is important as we then share that input with those who work with the models and maps! I plan to get soil moisture sensors installed in non-irrigated fields in York, Seward, and Clay this week as well.
Soil Moisture Sensors Tips: With cultivating and hilling progressing, some are now looking at getting soil moisture sensors installed. If you utilize watermark sensors, the following are some tips I’ve learned.
Test sensors with wet/dry process to remove all air bubbles:
- First, make sure sensors read 199.
- Then, soak sensors for at least 24 hours. They should read 10 or less (Jenny’s note-I realize they may read this in a matter of minutes to hours but it’s our best practice recommendation to ensure all air bubbles are removed).
- If they don’t read 10 or less, gently rub any soil loose on them with your fingers (don’t use a brush) and allow to continue soaking for another 24-48 hours. If they still don’t read under 10, I don’t use them.
- Best practice is to then allow the sensors to completely dry out again to 199 to complete the wet/dry process. (Jenny’s note: I realize, due to time constraints, many sensors get installed once they have been soaking and never go through the complete drying process).
Installation:
- Avoid installing sensors in saturated soil conditions in clayey soils. Doing so allows a thin clay film to develop on the sensors which then affects readings .
- Prior to installation, the sensors should be soaked again and installed wet. The soaking process only takes a matter of minutes to get back to 10 or below. I carry the water bucket with sensors with me into the field.
- When soaking, water moves into the PVC pipe, thus it can take time for the water to drain providing accurate readings if not removed. Some sensors have a hole drilled in the PVC pipe above the sensor to allow water to drain. Otherwise, it’s important to remove the caps and tip the sensors over to dump any water that has accumulated in the PVC pipe during the soaking process. I then put the cap back on, take my hand and wet the PVC pipe with water so it pushes in easier. Some like to use WD-40 but my concern with that is it getting on the sensor affecting readings.
- Install all sensors where the sensor itself sets using an ag consultant tube (can be 12 or 18 inches). An ag consultant tube has a slightly smaller diameter that provides a tight fit for the sensor. Use a regular soil probe for the foot above that. For example, for 1’ sensor, I use ag consultant tube. For 2’ sensor, I use regular probe for first foot and ag consultant tube for second foot. For 3’ sensor, I use regular probe for first 2 feet and ag consultant tube for third foot. The reason for this is in clayey soils that are wet, there’s greater resistance to pushing in that sensor, so this is one way I’ve found which is easier for someone like me to push them in. (Jenny’s note: many have installed sensors with a regular soil probe through the years and that’s also fine. Just know that you may see more water run along side of tube before soil makes a tight fit around where sensor is located. I’ve just found less issues with this when I use the process described above).
- NEVER pour water into the hole or make a slurry. Make sure the sensor hits the bottom of the hole as air gaps can make the sensor readings inaccurate. Some people find it better to not remove the entire amount of soil for a specific depth and then push the sensor the rest of the way till the correct depth is obtained. I’m not always strong enough to do that so do what works for you as long as the sensor is at the correct depth and there’s no air gaps.
After Installation:
- Make sure to fill in any gaps around the sensor with soil and make sure there’s no soil cracks around the sensors.
- Make sure to mark each sensor and flag them well.
- Sensor readings should equilibrate with the soil within 48-72 hours but especially within a week.
- If a sensor starts reading really dry, before replacing it, I often remove it and reprime it in the field. This can be done by re-soaking in water for 1 minute or so till it goes back below 10 and then reinstalling in same hole. If it doesn’t go below 10, I replace it. If it reads strange the next week, I also replace it.
ET gages:
- A reminder to use distilled water in the tube and to fill the ceramic top when you’re also filling the main tube. I usually fill the ceramic top and wait for it to soak up a little then fill again.
- Prime the ET gage ensuring no air bubbles are in the second tube with the stopper. I always overfill the ET gage to help with priming and ensuring there’s no air bubbles.
- Excess water can be removed and also air bubbles can be removed by gently pulling down on the glass site gauge tube at the rubber base and releasing extra water from it. Air bubbles can also be released in this process. Place the site gauge tube back in place when you are at a water level between ‘0 and 1’. Then place one red marker ring on that beginning start level.
- I always plan to refill the ET gage when it gets down to ‘9’ on the site tube.
- The green canvas cover should be replaced at least every 2 years and be sure to dust it off and the white membrane below it.
In another column I’ll share how to use the two tools together for irrigation scheduling. All videos and charts with more information can be found at: https://water.unl.edu/category/nawmn. This is a checklist I made awhile back with Daryl Andersen which has more detail and could honestly be updated: http://www.littlebluenrd.org/pdf’s/forms/etgage_sensor_checklist.pdf but may also be helpful.
Tree Damage: Recent windstorms have caused for many downed branches and even some trees. When removing broken branches or dead branches, it’s important to prune correctly for tree health. Correct pruning of larger branches can often involve 3 cuts per limb. The first two cuts are made away from the trunk of the tree to remove most of the weight of the limb. The third cut is near the trunk itself at the bark collar ridge where the tree will eventually seek to heal. I like this Backyard Farmer YouTube video as a good visual of correct pruning: https://youtu.be/9cl0Qxm7npk. Pruning is best done in the dormant season of February and March. It’s best avoided in April and May when trees are putting energy into new leaves and in the fall as fall pruning can result in growth instead of the tree preparing for and going into dormancy. Some great resources with more information on proper pruning are: https://go.unl.edu/v9uf, https://go.unl.edu/gdb9, and this blog post https://jenreesources.com/2014/04/20/proper-tree-pruning.
JenREES 6-3-18
Crop Update: So grateful for some rain for much of the area last week! Updated soil moisture status at http://jenreesources.com. The crops are rapidly growing now as are the weeds. Some were seeing Palmer shooting heads at soil level already…last year we
Palmer shooting a head at the soil surface. Photo courtesy Matt Kirchhoff.
didn’t see that till late July. Many have been in the process of postemergence herbicide applications. We revisited a CropWatch article regarding best management practice considerations for postemergence dicamba-based applications to corn based on the research that is available. Please see the full article with more explanation at http://cropwatch.unl.edu. Briefly, those practices include:
- Consider a quick irrigation (rainfast/irrigation timing based on label requirements for the product you’re applying) of only 1000 gal/ac to help reduce any potential volatility.
- Don’t use dicamba products in both corn and soybean to reduce selection pressure and resistance.
- Check for temperature inversions and wind speed. Temperature inversions can be tested by using Innoquest SpotOn® inversion tester and testing the temperature at 1 meter and 3 meters. If the temp is cooler at 1 meter than 3 meters, a temperature inversion is occurring and spraying is not recommended.
- Consider using the more restrictive RUP dicamba requirements regarding wind speed, boom height, etc. Also consider not using AMS with any dicamba product even though it is labeled for use in some of the corn dicamba products. This may result in you needing to increase the glyphosate rate to the highest labeled rate to increase efficacy. Amit Jhala will showcase research on efficacy of dicamba products with and without AMS at the South Central Ag Lab Weed Science Field Day on June 27.
Volunteer corn is also a major issue in many corn and soybean fields in the area and there’s two articles in CropWatch at http://cropwatch.unl.edu addressing this topic. A number of grass herbicides are available for control in soybean. The challenge is in the continuous corn fields. If you had glyphosate resistant corn last year and used a different technology such as Liberty or Enlist, you have some other options this year. For Liberty Link corn this year, two applications, each of 32 to 43 fl oz/acre, could be made. Remember that Liberty will NOT be effective if Roundup Ready + Liberty Link hybrid corn was planted last year. Regarding Enlist corn, Assure® II is the only grass herbicide labeled to control volunteer corn with this technology. It can be applied at 5 to 12 fl oz/acre in Enlist Corn for selective control of volunteer corn. Please be sure to read and follow all label requirements. A few farmers have also discussed their past experiences with cultivation, using either one or two passes and their concern about the soil moisture situation this year.
So how much yield loss can be anticipated from volunteer corn? Perhaps more than one would think with more loss occurring in soybean! Studies were conducted in several mid-western states at various densities including 3500, 5000, 7000 and greater volunteer corn plants per acre. To envision this, imagine 3.5, 5, and 7 volunteer corn plants respectively in 1/1000 of an acre (17’5” in 30” rows). Some fields this year have much higher densities than this! Clumps of corn impact yield more than individual plants.
UNL research found a volunteer corn density of 3500 plants/acre led to 10% yield reduction in soybean. Doubling the density to 7000 plants/acre led to a 27% yield reduction. South Dakota State University data revealed similar trends. A volunteer corn density of 5000 plants/acre resulted in a 20% yield reduction (12 bu/acre yield loss in 60 bu/ac soybean).
Clumps of volunteer corn in soybean led to greater yield loss as they were more competitive than individual plants. In the UNL study a density of 3500 clumps of corn/acre resulted in a 40% yield reduction. Researchers in Minnesota and Illinois also found increased competition with clumps of volunteer corn versus individual plants. Clumps of corn (7-10 plants/clump) were established at different densities. Depending on the location and year, soybean yield was reduced 1% for every 75-115 clumps/acre.
A recent UNL research study found highest yield reduction occurred when volunteer corn was left uncontrolled or when it was controlled too late at the R2 (full flower) soybean growth stage. The combined density at this greatest yield reduction was at 24,710 volunteer corn plants per acre plus 1,235 volunteer corn clumps per acre.
In corn, UNL research found a volunteer corn population of 3500 plants/acre resulted in a 2% yield reduction in corn. Doubling the density to 7000 plants/acre caused a 5% yield reduction. Clumps of volunteer corn led to greater yield loss as they were more competitive than individual plants. A density of 7000 clumps of corn/acre resulted in a 14% yield loss compared to a 5% yield loss with individual plants. So volunteer corn in general can be fairly competitive especially to our legume crops. It can also be a problem regarding harboring corn rootworm in soybean fields, reducing the advantage of the rotation from that perspective.
Also, an update on my soybean planting date demo at the fairgrounds: I wasn’t counting on rabbits! All the soybeans were reduced to stems below the point of recovery. So there is no demo but the groundskeeper preferred they took out my soybeans instead of his petunias 🙂 Will try again next year.
JenREES 5-27-18
Crop Update: Wheat is mostly in various stages of heading through pollination in this part of the State. The wheat scab risk prediction model (http://www.wheatscab.psu.edu/) was forecasting higher potential for scab in portions of Nebraska last week with a relax in the model this week due to higher temperatures and no moisture. Please keep an eye on your growth stages, the weather, and the model for risk of scab in your wheat.
Don’t have too much in the way of corn and soybean updates other than it’s good to see guys finishing planting and getting herbicide applications down. Waterhemp and palmer range in size from emergence to 4 inches from what I was seeing this past week.
Also a reminder to install irrigation scheduling equipment soon. It’s always easier to install earlier than when plants get larger! Check out this week’s CropWatch article at https://go.unl.edu/n0u0 which shares additional information about ET gage sites; reminders and tips for installing ET gages and watermark sensors.
Wheat and Field Pea Field Days: There are 11 upcoming wheat field days throughout the State, many of them coupled with field pea/pulse/cover crop field days as well. During the field visits participants will be able to learn more about different varieties of wheat, field peas, chickpeas and forages. Depending on the location, field visits will also include demonstrations of other specialty crops (lentils, winter canola, forages, cover crops) and effects that different agronomic practices (planting dates, seeding rates, fertilizer management, etc.) have on crop yield and yield quality.
Besides field visits, the field days will feature indoor sessions with a free lunch, a 30-minute networking session, and brief research updates. Networking sessions will allow participants to meet with seed, processing, and marketing businesses critical to pulse cop industry development in Nebraska. The research updates will include: Production and marketing of pulse crops, Incorporating cover crops in wheat and field pea cropping systems, and Wheat production – management for higher yield and grain protein. Area dates/locations are listed below and all flyers with additional information can be viewed at: https://go.unl.edu/vto8.
- May 30: Wheat Field Day, 6:30 p.m. at Fairbury, RSVP rpryor1@unl.edu
- June 12: Wheat and Pulse Crops, 9 a.m. at the UNL ENREC near Mead, RSVP nathan.mueller@unl.edu
- June 18: Wheat and Pulse Crops, 9 a.m. near Callaway and at North Platte (UNL WCREC), RSVP sstepanovic2@unl.edu
- June 19: Wheat and Pulse Crops, 8:30 a.m. near Grant (UNL Stumpf Wheat Center), RSVP sstepanovic2@unl.edu
- June 20: Wheat and Pulse Crops, 9 a.m. near Alma and Bladen RSVP sstepanovic2@unl.edu
Nebraska Field Pea Field Days are free, thanks to sponsorship by the Sustainable Agriculture and Research Education (SARE) in Nebraska, the Nebraska Environmental Trust, and the pulse crops seed and processing industry.
South Central Ag Lab (SCAL) Weed Science and Cover Crop Field Day: View demonstrations of new technologies and herbicides for weed control in corn, soybeans, and sorghum and effects of cover crops on soil health and pest management at the June 27 Weed Management and Cover Crops Field Day. It will be held at the South Central Ag Lab near Clay Center. The day begins with registration and rolls at 8 a.m., followed by weed management tours from 8:30 a.m. – noon, and cover crop demonstrations from 1 to 3 p.m. A free lunch will be served. In addition to the field demonstrations, Jim Specht, University of Nebraska-Lincoln professor emeritus, will presented on “Optimizing Soybean Planting Date, Seeding Rate, and Seeding Depth in Nebraska.” CCA credits will be available. Please pre-register at: https://agronomy.unl.edu/fieldday. The South Central Ag Lab is 4.5 miles west of the intersection of Hwy 14 south (to Clay Center) and Hwy 6 or 12.4 miles east of Hastings on Hwy 6. GPS coordinates: 40.57539, -98.13776.
Tours Include:
- Comparison of Herbicide Programs for Weed Control in Soybean including Roundup Ready 2 Xtend and Liberty Link Soybean, Examples of spraying the wrong herbicide on wrong soybean herbicide-resistant cultivar, Weed removal at different growth stages and yield impacts, and Understanding multiple herbicide-resistant soybean herbicide programs.
- Comparison of Herbicide Programs for Weed Control in Corn including glyphosate and glufosinate-resistant corn in addition to several new corn herbicides, response of white and yellow popcorn to various herbicide chemistries and off-target movement, control of volunteer corn in Enlist Corn, and Weed Control and Crop Response in INZEN sorghum.
- An Overview of the Effects of Cover Crops on weed suppression, pests (particularly wheat stem maggot) and beneficial insects. Cover Crop Effects on Soil Health, including changes in soil microbial communities and soil physical properties with a focus on cover crop root biomass.
JenREES 5-20-18
Crop Update: So grateful for rain and truly hope those who wanted and needed rain received it! An update to soil moisture profile as of 5/17/18 can be found at http://jenreesources.com.
A number of crop issues surfaced this week. One being root burn and wilted-looking corn seedlings from anhydrous ammonia applications with the dry winter/spring we’ve had thus far. Anhydrous ammonia can expand in soils 2.5-3” in all directions and potentially more in dry soils. Pivots were running to help with that and hopefully rain events will help non-irrigated fields that were suffering in this way. Another problem observed in some non-irrigated corn fields has been fomesafen carryover injury from products such as Flexstar, Reflex, Prefix, etc. These products have a 10 month planting window back to corn which is fine in most years, but dry conditions didn’t allow for the herbicide to break down in all situations from applications last June. This active ingredient is in Group 14 (PPO inhibitors) and the injury from this particular active ingredient is unique in that it causes yellow/brown striping of the veins themselves instead of interveinal chlorosis/necrosis. Seedlings most affected right now are found on field edges or wherever there was overlap of application. Hopefully corn should grow out of this injury in time. Herbicide carryover may be a something to watch for in soybean as well from other active ingredients. We also saw regrowth occurring on plants affected by wind/dust/debris damage but there are situations where replanting will be needed on endrows, etc. Roger Elmore has a photo gallery explaining regrowth in this week’s CropWatch at http://cropwatch.unl.edu.
Another situation that surprised me this year was finding seed corn maggot damage in
Seed corn maggot feeding on soybean seed. No insecticide was included in the seed treatment.
Seed corn maggot affecting soybean seedlings by feeding on cotyledons and hypocotyls. The brown grain-like structure in the bottom of the picture is a seed corn maggot that is pupating. These seeds did not have an insecticide in the seed treatment.
soybean. At first I was puzzled as the beans were clearly treated but then learned the beans didn’t have an insecticide added to the seed treatment. In scouting a number of fields, I’ve actually seen quite a bit of seed corn maggot damage, particularly in tilled fields and those with manure applied or those with cover crops that were green or where termination included tillage. I’ve also been surprised how many have told me they don’t use an insecticide seed treatment on early planted beans. We didn’t have any research in our early soybean planting studies without insecticide + fungicide seed treatment so we just automatically recommend both. Unfortunately this year we’re seeing what can happen without it with higher insect pressure in some fields. For seedlings with the insecticide seed treatment, I’m seeing light scarring on the cotyledons and hypocotyls but no maggot penetration. In fields without the seed treatment, I’m actually seeing penetration of the cotyledons and hypocotyls. The good news is that most of the maggots were also pupated, pupating or will be soon. But it is something to watch for, particularly in fields that have been tilled and especially if manure was applied or they were tilled and had a cover crop on them. They are not as attracted to no-till fields. Regarding stands, from my experience with soybean pops and stand loss due to crusting, hail, herbicide injury, etc., I keep stands of 60,000 plants/acre or more. It really stinks to talk about replanting anything right now with guys still trying to finish planting. If you choose to replant soybeans, consider proving it to yourself by planting strips and leaving strips. If you’re interested in that, I’d be happy to work with you. You can learn more about seed corn maggots here: https://crops.extension.iastate.edu/cropnews/2016/04/look-seedcorn-maggot-corn-and-soybean.
Wheat in the area ranges from boot to flowering. A couple of wheat fields I know of
Wheat field cut at boot stage for hay.
were taken for hay. For those still considering silage, check out the CropWatch article this week where Todd Whitney shares data on wheatlage (wheat silage): https://go.unl.edu/qkbr. The rainfall will greatly help our wheat right now. And, rainfall at heading to flowering makes me think about the potential for Fusarium Head Blight (scab). The wheat scab prediction monitor http://www.wheatscab.psu.edu/ is predicting medium to high risk for scab in Nebraska for the next 48-72 hours. Some years I feel the model is delayed in prediction, but I still feel it’s a good tool and resource. Scab is caused by Fusarium graminearum and is favored by warm (70-80°F temps), humidity, and rain events before and during flowering. Once wheat begins flowering (Feekes 10.5.1), many foliar wheat fungicides are off-label. In fact, recent research presented at the 2017 Fusarium Head Blight meetings shows that in general, strobilurin products can actually increase the presence of deoxynivalenol (DON) in wheat if applied at full heading (Feekes 10 or 10.5). Thus, your better fungicide options for preventing scab are Caramba and Prosaro and these products can also kill any fungal diseases present on leaves (such as powdery mildew, tan spot, and rust). These products aren’t 100% for scab prevention due to the variation of heading and flowering that occurs in so many fields. Better efficacy is obtained with more uniform plants which begins at seeding time. So I would recommend watching the growth stage in your fields, the weather, and the prediction tool regarding if you feel you need to treat any fields this year to prevent scab. Research has shown best efficacy to be obtained when at least 50% of the plants are at 1/3 flowering. Flowering begins with yellow anther sacs in the middle of the head with flowering continuing throughout the head from there. Once the pollen is released, the anther sacs turn white.
LBNRD Open House Public Hearing: The Little Blue Natural Resources District (LBNRD) is hosting a public hearing on May 29th from 6:30-9:00 p.m. at the Davenport Community Center in Davenport, NE. The purpose of the hearing is to provide information and receive testimony on proposed amendments to Groundwater Management Rules and Regulations. The hearing will be an open house format allowing individuals to ask questions of the NRD staff, look at exhibits, and offer testimony. The proposed rule changes and additional information can be found on the LBNRD website at: http://www.littlebluenrd.org/. Please contact the NRD with any questions at (402) 364-2145.
Not part of my news column: on a more positive note after mentioning all the crop problems, the lilacs in general were beautiful and smelled amazing!!!
JenREES 5-13-18
It was great to see so many fields of corn and even soybean emerging throughout the
area this past week! Also grateful for the rain we received in York and for those who received some in other areas. There are still areas who continue to miss rains and I remain concerned about the soil moisture situation. I have another soil moisture update this week at http://jenreesources.com if you’re interested in checking that out.
Thursday night/Friday morning’s high winds caused some damage with overturned pivots/corner systems and tree damage. We also saw newly emerged corn and even soybean cut off or
Corn plants were buried or cut off by blowing residue/soil. A few remaining plants in this area of the field can be seen.
buried due to blowing debris/soil, particularly in soybean stubble. It will be important to watch the plants in these fields the next several days. By late Friday afternoon, I was already seeing new growth occur, which is good. Typically, that has been the response in the past-new regrowth in corn as the growing point is still below ground. However, it will be important to watch the corn plants for any bacterial issues that may kill seedlings. One can also split open a few plants and look for a healthy growing point. Regarding the soybean, I have seen soybean lose cotyledons due to hail, crusting, freeze, and wind damage, and still produce a plumule at the top of the soybean stem. It’s just hard to know for sure what will happen so it’s best to watch the plants in the fields.
Wheat in Nuckolls, Thayer, and Webster counties ranges from elongation to near boot and is turning blue-gray from moisture stress. Wheat is a crop that I’m always learning about-it can look really bad (or really good) and then end up surprising a person regarding yield either way. Lower leaves
in fields are turning yellow-brown. Some of this is due to moisture stress while there’s also powdery mildew pretty thick in lower canopies of wheat that had more tillers. A few have talked with me about using the wheat for hay or silage and then potentially going in with short season corn, sorghum, or a forage crop. Our forage specialists would recommend that if the wheat variety has awns, it’s best to either take for hay or silage at the boot stage so the awns don’t cause issues with livestock feeding. Todd Whitney, Extension Educator in Phelps/Gosper counties, had worked with a feedlot using an awnless wheat variety. Because of the additional growth that occurs in wheat (and other small grains) from boot to full head elongation, they found biomass production may be increased 25% if the forage was harvested during the later pollination period.
Evergreen Trees: There’s also been a lot of evergreen tree questions. For those noticing spruce trees looking kind of yellow with early morning sunlight, spruce spidermites have been working hard with the cooler, dry weather. They tend to build populations in spring and fall. You can check for spidermites by taking a white piece of paper and banging the needles on it. Then look for the presence of tiny dark green to nearly black spidermites crawling on it. Rainfall is a great way to wash them off of trees as are strong streams of water (easier done with smaller trees). There are also a number of miticides available that homeowners can purchase from lawn and garden stores (look for products that say they can be applied to trees for control of spidermites). A great brochure on insect pests of evergreen trees can be found at: https://nfs.unl.edu/documents/foresthealth/insectevergreen.pdf.
Many of us also noticed our spruce trees turning red/brown/purple/yellow in color last fall. This is most likely a disease called needle cast of spruce and can be prevented by spraying trees now (mid-May) with a product containing copper sulfate. Regarding Ponderosa or Austrian pines, if you look closely at the needles and observe dark bands or rings on them followed by death of the needle either direction from the band, the tree problem is most likely due to a fungal needle blight like dothistroma or brown spot in Scotch pines. They can all be prevented by spraying a fungicide containing copper sulfate now. The following brochure on diseases of evergreen trees is really helpful: https://nfs.unl.edu/documents/foresthealth/diseasesevergreen.pdf. Sometimes the problem is finding the products listed on these brochures in our smaller towns as these brochures were developed in Lincoln. If these specific products aren’t available from your local lawn/garden store, box store, or coop, I would recommend looking at the products available and look for a product that says it is effective against needle blights on trees. Not all the products I’m seeing have copper as an active ingredient, but other fungicides are listed and the key would be the fact that the site (trees) and even better, the site with problem (trees with needle blights), is listed on the label.
We also continue to see pine wilt affecting our Scotch (short needles in groups of 2) and Austrian pines (long needles in groups of 2). Pine wilt disease is caused by the pinewood nematode that is carried within the gut of a long-horned beetle. The beetle is what creates the ‘shotholes’ often seen in bark of infected trees. The nematode is native to Nebraska, as are Ponderosa pines (long needles in groups of 2 and 3). This is why we don’t see the problem in Ponderosa pines but do in Scotch and Austrian, which are non-native to Nebraska. A tip, if you’re trying to distinguish Ponderosa vs. Austrian pines, anytime you see needles with a group of 3 it’s a Ponderosa. Pine wilt is caused by beetles carrying pinewood nematodes vomiting them into the water-carrying vessels of the tree (xylem). The tree senses the nematodes and essentially blocks water to those branches. Often you will observe a branch then perhaps a side of the tree and eventually complete death of the tree within 6-9 months. While I have diagnosed many samples of pine wilt, more often when I visit homeowners the tree problems are due to fungal diseases which occur on the needles.
Lawns: Please remember the importance of sweeping or blowing fertilizer and pesticide products back into the lawn instead of leaving them on sidewalks. Leaving them on the sidewalks puts them in contact with people and pets walking on sidewalks and moves them into storm water systems via rain that can eventually end up in streams. I’m also seeing a number of 2,4-D/dicamba products being sprayed around tree bases to kill weeds which is affecting the new growth emerging on trees. Consider applying a wood mulch layer around the base of trees to help avoid this situation in the future and be sure to read and follow all pesticide labels.
JenREES 5-6-18
What a beautiful weekend! It was a welcome change from the winds we received last weekend and early week. The high winds early in the week created difficult situations from many perspectives-soil loss, visibility, accidents, and drying out the seed bed.
Great to see several on-farm research plots going in and to have some new cooperators this year! I also started a very small soybean planting date demo at the York County Fairgrounds on April 24. A farmer on Twitter was encouraging other farmers to try planting a few seeds every week for yourselves in a garden plot and count the nodes and pods. Thought it was a great idea and will have it signed at County Fair regarding soil temps for first 48 hours and nodes. Thanks to Jed Erickson from Pioneer for the seed!
Rain events on May 1-2 allowed for some soil moisture recharge in the first and second feet in some locations. Unfortunately, the rainfall was still fairly spotty. We could really use rain overall for getting moisture back into drying seedbeds, activating herbicides, and settling dust. Pivots are running in some fields because of these factors. I provided an update on the locations I’m monitoring regarding soil moisture as of 5/3/18 on my blog at http://jenreesources.com. The farmers were interested in continuing this monitoring throughout the growing season this year, so will continue sharing as often as I can.
Wheat: Wheat’s joined in the area and ranges in height depending on soil moisture. For the past few weeks we’ve been noticing yellowing leaves. Some of that may have been due to cold temperatures. I was also seeing powdery mildew within the canopy of several fields I looked at. No rust has been observed yet in Nebraska fields. I also noticed tan spot in wheat on wheat fields. One concern was the cool weather has allowed for bird cherry oat aphids in area wheat. My concern is that they can vector barley yellow dwarf virus which is one we see when the flag leaf emerges. According to K-State, there’s not strong developed thresholds. They’re recommending if 20 or more aphids are observed per tiller with lady beetles observed on fewer than 10% of tillers, spraying may be justified.
Lawn and Garden Information: With this year’s cool spring, crabgrass preventers can still be applied the first few weeks of May. Germination begins with soil temperatures around 55F but prefers warmer soil temps. UNL Lawn calendars for Kentucky Bluegrass, Tall Fescue, and Buffalograss and all UNL lawn resources can be found at https://turf.unl.edu/turf-fact-sheets-nebguides. Mowing heights should be maintained at 3-3.5″ for the entire year. We also recommend just mulching clippings back into the lawn to allow for nutrient recycling. If you like to use mulch for your gardens, it’s important to read pesticide labels on products applied to your lawn. Some labels say it is not safe to use the clippings as mulch. Others say to wait at least three mowings before using the clippings as mulch.
Garden centers have been busy with the warmer weather and some have asked about temperatures for hardening off transplants. Kelly Feehan, Extension Educator in Platte County shares, “May is planting time for most annual flower and vegetable transplants. To avoid transplant shock and stressing young plants, wait for soils to warm up and take time to harden off transplants. Soils are colder than average this year so waiting to plant will be beneficial. And then, plants moved directly from a warm, moist greenhouse to windy and cooler outdoor conditions will be stressed by transplant shock. This can negatively affect plant growth, flowering, and vegetable production. Harden off transplants by placing them outdoors, in a protected location, for at least a few days before transplanting outdoors. Another way to harden transplants is to plant them in the garden, then place a cardboard tent or wooden shingle around them for a few days to protect them from full exposure to wind and sun. Planting young transplants on an overcast, calm day or during the evening also reduces transplant shock.” Specifically when it comes to tomatoes, it’s best to wait till mid-May otherwise “gardeners who plant earlier need to be prepared to protect tomato plants with a floating row cover or light sheet if cold threatens. To help tomato transplants establish quickly, begin with small, stocky, dark green plants rather than tall, spindly ones. Smaller plants form new roots quickly and establish faster than overgrown transplants. Do not plant too deep or lay tomato stems sideways. Although roots will form on stems below ground, this uses energy better used for establishment. Use a transplant starter solution after transplanting tomatoes to be sure roots are moist and nutrients are readily available in cool soils. Wait until plants are growing well before mulching or mulch will keep soils from warming and may slow tomato growth.”
JenREES 4-29-18
Crop Update: It’s nice to see some signs of spring with planters going this 
week/weekend, crabapples and flowering pear trees in bloom, and tulips budded! The York County Corn Grower plot got planted on Saturday and grateful for Ron and Brad Makovicka’s efforts with that and for all our participating companies!
Rain did help the top foot of sensors in some locations I’ve been monitoring for pre-plant soil moisture. The graphs will be up at http://jenreesources.com by noon on Monday. The cooperators have all been interested in continuing to monitor moisture in these fields post-planting, so will plan to do that and add a York and Seward location too. I’m noticing in York as lawns are greening up, that portions are looking gray-green in color where trees are located in them.
As of April 26th, I hadn’t found any wheat jointing yet. The growing point was just approaching ground level in several fields I checked. We also need to keep an eye out for stripe rust as incidence is increasing in Kansas fields. There’s articles focusing on winter wheat in this week’s UNL CropWatch at http://cropwatch.unl.edu including nitrogen management and Nebraska wheat progress.
Wheat Stem Maggots (WSM) in Rye/Wheat Cover Crops: I meant to provide an update in last week’s column. Dr. Justin McMechan has been scouting wheat and rye cover crop fields for wheat stem maggots. So far, he captured one adult wheat stem maggot on April 16 in 100 sweeps from a wheat cover crop planted in late September at the Eastern Nebraska Research and Extension Center near Ithaca. He shared that “adults have been consistently collected at this location since first emergence with one to two found per 100 sweeps. This first occurrence of adults matches closely with data collected in 1933 by Merle Allen from Kansas State University. Our latitude north of Kansas and cold spring suggests this emergence might be earlier than Allen’s data. On April 23 two adults were collected at Clay Center and a single adult was collected near Marquette. Cover crops in these fields were less than 6 inches in height, with the field near Marquette grazed to approximately 3 inches in height. Sweeping these fields is challenging due to the height of the vegetation so adult captures are not likely to represent true numbers in the field. If you are skilled with a sweep net, we encourage you to sweep your wheat, rye, or triticale cover crops for wheat stem maggot adults.” At this point we’re not recommending any insecticide treatments. An interesting observation that a couple of Clay and Adams county farmers mentioned to me last year was they noticed the presence of a lot of flies as they planted corn into green rye and terminated at or after planting corn. The adult WSM is a small fly and you can see photos in Justin’s report in this week’s UNL CropWatch at http://cropwatch.unl.edu.
Which dicamba product before Xtend soybean: This has been a fairly common question this spring which Dr. Amit Jhala addressed in this week’s UNL CropWatch. I’ve also provided his answer here. “I recently received several phone calls from growers with questions on terminating broadleaf cover crop species and broadleaf weeds using dicamba products. They were particularly interested in whether dicamba products such as Banvel, Clarity, DiFlexx, etc. can be applied to terminate broadleaf cover crop species such as hairy vetch, field peas, or mixtures and broadleaf weeds such as henbit, field pennycress, or marestail immediately before planting Xtend soybean. The answer for the dicamba-based herbicides listed above is NO. Their labels have soybean planting intervals of 14 to 60 days, depending on the product and its use rates.
For example, for Clarity to be applied at 16.0 fl oz/acre, there would be a 28-day soybean planting interval after an inch of rain. If Clarity were to be applied at 8.0 fl oz/acre, the soybean planting interval would be 14 days after an inch of rain. The Clarity label also specifies: “Do NOT make Clarity burndown applications to soybeans in geographic areas with average annual rainfall less than 25 inches.”
If DiFlexx is applied burndown at 24 fl oz/acre or less, the planting interval for soybean is 60 days. This longer planting interval must be applied because Xtend soybean is not listed on Banvel, Clarity, DiFlexx, or other dicamba products.
Dicamba-resistant soybean, also known as Xtend soybean, became available commercially for the 2017 growing season. Three dicamba products (FeXapan, Engenia, XtendiMax) are labeled to be applied pre-plant, pre-emergence, or post-emergence (up to R1 soybean growth stage) for broadleaf weed control in Xtend soybean. You can use FeXapan, Engenia, or XtendiMax as per label requirements in burndown application and plant Xtend soybean without a planting interval.
If you apply 2,4-D prior to planting soybean, be sure to adhere to the planting interval specified on the label. Several 2,4-D products have different planting intervals for soybean, ranging from 7 to 30 days depending on product and application rate. (See this Crop Watch article.)”
JenREES 4-22-18
Planting Considerations: This email newsletter reaches a wide area of the State, so soil temps vary quite a bit and some of you may be in better planting conditions than others. We still recommend planting into soil temps as close to 50°F as possible, check weather conditions for next 48 hours to hopefully maintain temps 50°F or higher, and avoid saturated soil conditions. If planting a few degrees less than 50°F, make sure to check with seed dealers on more cold-tolerant seed. This is most likely common sense, but I still feel worth mentioning. Everything we do at planting sets the stage for the rest of the year. We’re blessed to have equipment that can allow for many acres to be planted in a short amount of time. And…we also have the ability to mess up a lot of acres in a short amount of time.
Planting depth is also key. Aim to get corn and soybean in the ground 1.5-2” deep. This is critical for correct root establishment in corn to avoid rootless corn syndrome. Rootless corn syndrome is when the nodal (crown) roots don’t get well established and successive brace roots can’t establish either. This allows the seedling to whip around in the wind, potentially being dislodged, become weak or die. With center-fill planters, when adjusting down-pressure on the go, sometimes the planter ends may not always be seeding as deep as the center. Too often I’ve seen that resulting in seed 1” or less and the field pattern can be observed the entire growing season with potential yield impacts. So don’t just rely on the monitor. Take the time to dig up seed behind the planter and at spots along the whole planter length to ensure the proper seeding depth. And do this with every field, particularly with different tillage/residue situations. I realize this takes time, but you’ll be glad you did to catch any issues before too many acres are planted incorrectly.
With cold temps or higher soil moisture conditions, it’s still important to get that seed at least 1.5-2” in the ground. Planting 1.5-2” deep helps both corn and soybean to have that seed in even soil temperature and moisture conditions. You may be surprised on that recommendation for soybean, but I think it’s even more critical with planting early. In fact, UNL research near Mead compared planting depths of 1.0, 1.25, 1.5, 1.75, 2.0, 2.25, and 2.5 inches in 2011 and an additional planting depth of 2.75 inches was added in 2012 and 2013. The study found lowest yields when soybean was planted 1.25” or less or 2.25” or greater with the highest yield at 1.75” deep. One of that study’s hypotheses was that planting deeper would buffer soil temperature and moisture and protect newly emerged seedlings from frost and freeze damage, particularly when planting early in the season.
Hopefully planting soybean early is still something you’re considering for this year! We wrote a CropWatch article this week at http://cropwatch.unl.edu to provide some updated research on amplifying the effects of planting early. There’s so much research regarding how early soybean planting increases yield that we wanted to share new research regarding maturity groups, etc. Essentially, what it appears from the research thus far, is that it’s more important to choose a consistent, high-yielding soybean for your area, regardless of specific maturity group. We’d like to get more specific data and have on-farm research protocols available to compare MG2.4-2.5 vs. MG3.0-3.5 and Dr. Jim Specht would also like to collaborate with us on documenting various factors. Please let me know if you’re interested in this! There’s also a protocol for comparing early vs. late planting of soybean.
Soil moisture conditions didn’t improve this week at the six sites I’m monitoring in Webster, Nuckolls, Thayer, and Clay counties. You can find the chart comparisons on my blog at http://jenreesources.com. Last weekend’s bizzard didn’t provide significant moisture in this area. With pastures slow with growth and drought increasing in Kansas, discussions with farmers have included cover crop termination, grazing rye that’s had anhydrous ammonia applied to it (with the original intention of termination and planting to corn), and grazing wheat. Most of these topics are included in this week’s UNL CropWatch at http://cropwatch.unl.edu. The articles are too long with too many considerations for me to add them in this news column, so please do check them out if you’re interested in these topics. Another topic I’ve had several questions about is regarding how temperature and rain affect burndown herbicide applications. Dr. Amit Jhala, Extension Weed Specialist, addresses that in this week’s CropWatch as well, so please check that out. Here’s wishing everyone a safe planting season with conditions to get #plant18 and #grow18 started off well!
JenREES 4-15-18
Well, winter seems to be sticking around. My thoughts and prayers have been with those of you calving with the difficult conditions this year.
I provided an update regarding soil moisture status in non-irrigated fields both in this week’s UNL CropWatch at cropwatch.unl.edu and my blog at jenreesources.com. We’ll see what happens with moisture in the next few weeks and I’ll post updates to my blog.
Very few have tried planting in this part of the State that I know of. Grateful for all of you who keep me updated on what’s going on through your questions and comments! In this week’s UNL CropWatch, Dr. Roger Elmore took the lead on an article addressing corn planting. The message is to ideally wait till soil temperatures reach 50F with weather conditions allowing soil temperatures to remain at 50F or higher for the next 48 hours. We’ve observed when seed was planted and a cold snap with cold rains was received within 48 hours, some problems with seed germination and emergence. Hybrids vary in cold tolerance and seed companies are a great resource for that information as to which hybrids could be planted first in colder soils. Soil temperature information can be found at the UNL CropWatch site at: https://cropwatch.unl.edu/cropwatchsoiltemperature. We’d also recommend you take the soil temperature in the field before you plant and can do so by using a meat thermometer.
Last year I remember receiving questions from April 21-24 regarding planting corn and soybeans with an anticipated cold snap later that week. At that time, I was recommending growers switch to soybeans. The reason? Soybeans imbibe (uptake) water more quickly than corn seeds and while we hear 48 hours to be on the safe side, the critical period is more like 24 hours. Also, several years of both small plot and on-farm research in Nebraska has shown the primary way to increase soybean yields is to plant early. Dr. Jim Specht’s research showed soybeans produced a new node every 3.75 days once V1 occurs. The nodes are where pods and seed occur. Our on-farm research planting date studies also showed regardless if the spring was cold/wet or warm/dry, the early planted soybean always out-yielded the later planted with a total average across trials of 3 bu/ac. The data ranged from 1-10 bu/ac. We never planted early without using an insecticide/fungicide seed treatment to protect that seed, so we recommend you add that if you do plant early.
Our recommendation would be to plant the last week of April or as close to May 1 as conditions allow. We’ve also seen good results after April 20 in years if the soil temperatures were around 50F with good weather conditions at least 24-48 hours after planting to maintain that soil temp. It’s important to know your level of risk, though. Crop Insurance planting date for replant considerations is April 25 and there may also be replant options from your seed suppliers. We never replanted any of our studies and I have only observed frost on soybean cotyledons one year where growers planted early with soybeans coming out of it. We had the largest number of acres I’ve seen planted by April 24 last year with thankfully no issues and they were able to take advantage of a high-yielding bean year. Perhaps this is something you wish to try for yourself this year? Consider planting some passes of soybeans early and come back with some passes three weeks later. You can use this Soybean Planting Date Protocol if you’re interested in trying this for yourself. Please let me know if you’re interested in this!
Depending on the number of acres you have, some growers are now planting soybeans first. Others are planting corn and soybeans at the same time by either running two of their own planters/drills or custom hiring someone to plant soybeans for them. This also spreads risk and can help with harvest. Regarding maturities, a study conducted at UNL East Campus compared a 2.1 vs. 3.0 maturity group variety at 10 day intervals beginning April 23 through June 19. Yield was highest for early planted soybean and a yield penalty of 1/8 to 1/4 bu/ac per day of delay in planting for MG2.1 and MG3.0 varieties, respectively was found. The study also indicated that yield of the MG3.0 variety was higher relative to the MG2.1 variety in early plantings (late April and early-mid May), but the opposite (greater yield in MG2.1 versus MG3.0 variety) was found for late plantings (late-May and June). In our part of the State, we’ve observed really high yields from strong genetics in the MG2.4-2.5 varieties when planted early; so I have a hard time automatically recommending later MG varieties without more data. Thus, I would love to work with anyone interested in planting early comparing a high yielding MG2.4-2.5 vs. a high yielding MG3.0-3.5 to obtain more data. Here’s a Soybean Maturity Group Comparison with Early Planting protocol to consider and please let me know if you’re interested in this!
Wheat: My colleague, Dr. Nathan Mueller in Dodge County, has taken the lead on
Nebraska crop reporting districts for wheat. The yellow area is considered ‘Eastern Nebraska’.
sharing wheat information for Eastern Nebraska. He’s put together an excellent resource on his blog at http://croptechcafe.org/winterwheat/. Every Friday he’s sharing an update called “What’s up this Wheat“. He also started an Eastern NE wheat listserv and his website explains how to subscribe to it. Grateful for his effort in this as we both have goals of increasing crop diversity in the areas we serve and there are many benefits to wheat in rotation!
Crabgrass prevention in Lawns: Just a quick note that while our Extension lawn calendars promote applying crabgrass preventer in mid-April, our horticulture experts say to wait till soil temperatures are 55F on a seven day average and we are currently far from that! Check out https://cropwatch.unl.edu/cropwatchsoiltemperature for soil temp info.
JenREES 4-8-18
Reducing Soybean Seeding Rates: Can I reduce soybean seeding rates and still maintain yield? It’s a common question from soybean growers, especially those seeking to reduce input costs. Every year during winter meetings I share what our growers have found. We now have 11 years of On-Farm Research proven data.
The findings? Reducing soybean seeding rates from 180,000 or 150,000 seeds/acre to 120,000 seeds/acre doesn’t statistically reduce yields in 30- or 15-inch rows in silty clay loam and silt loam soils in south-central and eastern Nebraska. Results of 18 studies showed for seeding rates of 180K, 150K, and 120K seeds per acre, average yields were 69.0, 68.7, and 68.4 bu/ac, respectively (Figure 1). The early studies within this dataset all had seed germination of at least 90% listed on the seed bag. In all but two situations (seeded at 180,000 and achieving 88% germination), the growers were able to achieve 90% or greater of their planted stand.
Figure 1. Yield results of on-farm seeding rate studies from 2006 to 2017 (15″ and 30″ rows). Average final stands: 90,000 = 83,067 plants per acre (ppa); 120,000 = 106,863 ppa; 150,000 = 132,700 ppa; and 180,000 = 157,924 ppa
As I share this data, I’ve often heard “but I seed higher rates because of X, Y, or Z…”; however, this dataset includes a lot of those reasons without negative yield consequences! I’ve worked closely with these studies in walking the fields; taking notes and pics; counting plants, pods, and seeds; so I’m really confident of the research and the fact that soybeans truly compensate for reduced populations! Outside of this research, I’ve also observed this in many soybean hail, crusting, and PPO inhibitor seedling damage situations. This dataset includes:
- The latest soybean varieties as the research was conducted from 2006-2017.
- Erect and bushy type varieties in growth architecture.
- Higher and lower yielding situations.
- Fourteen irrigated fields and four non-irrigated.
- Hail events occurring from cotyledon stage to R2 in some of these fields.
- Crusting in some non-irrigated fields.
- Seed treated in some fields and others without (determined by grower’s planting date).
- In some years, pod and seed count data were also collected; the data showed similar numbers of seeds/acre and ultimately yield per acre.
- Observations of increased plant branching at lower seeding rates and difficulty in telling the seeding rate treatments apart as the season progressed.
Our research data for 11 years shows no statistical yield differences in seeding rates from 120,000-180,000 seeds/acre in 15- or 30-inch rows in silty clay loam or clay loam soils. Thus, reducing seeding rates is a way to consider reducing input costs for 2018 without impacting your yield. If you dropped your seeding rate from 150,000 seeds/acre to 120,000 seeds/acre, you could save $10.08/acre, assuming a yield loss of 1 bu/ac, a seed cost of $60 per 140,000 seeds, and a savings of $25.71/ac on seed.
- Thus, if you plant between 140,000-160,000 seeds/acre, consider dropping your seeding rate to 120,000 and aiming for a final plant stand of 100,000 plants/ac based on our research findings.
- If you plant at 180,000 or more seeds/acre, consider dropping your seeding rate to 140,000 seeds/acre as a step-wise increment.
Still hesitant? Consider trying this yourself for your location! Consider using either this Two Population Treatment Design or Four Population Treatment Design. You also can download the Nebraska On-farm Research app, available in Apple and Android, to help you set up your plot design to obtain scientific results. If you have questions or need help setting up your research project, please contact me or anyone involved with our Nebraska On-Farm Research Network. To view all the graphs and additional data regarding 15″ row spacing with reduced seeding rates, please check out this week’s UNL CropWatch at http://cropwatch.unl.edu.
Beginning Soil Moisture: On Good Friday, I installed soil moisture sensors down to 4′ in 
non-irrigated no-till fields at Bladen and Lawrence. Last week I added three more sites at Clay Center, Superior and Byron. Thus far, the 3′ and 4′ are dry in all those locations other than Clay Center (only dry at 4′). At Superior, I could only get the soil probe in the ground 6″ into actively growing rye and 1′ in cover that winter-killed. I was just curious what kind of moisture existed currently in the southern tier of counties. I realize planting plans are in place and that we often receive rains in April/May. Hopefully it provides information that can be helpful in how to use that soil moisture. If we don’t get necessary rains, you may consider switching to a different crop, growing feed if you have cattle, or not terminating actively growing rye as originally planned but perhaps using it for feed. Will share graphs next week and I appreciate the growers allowing me to install these in their fields!
JenResources 