This Memorial Day will be different not gathering to honor those who have gone before us. Grateful for those who paid the ultimate sacrifice for our freedom! May we still take time to honor them.
Crop Update: Several weeks ago we were seeing large numbers of seed corn maggot flies. This past week have seen and heard reports of seed corn maggots attacking soybean seed/seedlings. Typically insecticide seed treatments provide protection; the exception is with high densities such as what we’re experiencing this year. They’re attracted to cover crop fields, fields with manure application, and tillage. There’s several generations but we shouldn’t have to worry about it again unless we experience replant situations. Fly emergence for the first three generations occurs when 354, 1080, and 1800 growing degree days have accumulated, respectively since January 1. There’s an updated article in CropWatch this week sharing more. They can reduce stands, but soybeans can withstand a great deal of stand loss. We recommend to leave a stand of at least 50,000 plants per acre with fair uniformity. That goes for anything that can reduce a soybean stand such as crusting, hail, herbicide damage, insects, disease, etc. We have research showing that the early planting will out-yield a replant. I realize there’s other considerations such as weed control and Dr. Shawn Conley at Wisconsin suggested putting the dollars into weed control instead of replant. They only found 2 bu/ac yield difference in stands of 50,000 plants/ac vs. optimal stands of 100,000-135,000 plants/ac. If you do consider replanting for any reason, we’d recommend going in next to the old stand with a similar maturity and proving it to yourself. Here’s a protocol if you’d like to test it yourself: https://go.unl.edu/wq24.
Post-Herbicide Applications: At pesticide training, I talk about the importance of overlapping residual. Ag industry partners talk about this too. It means aiming to apply the post-herbicide before the residual from the pre wears out. Many of us have seen fields that are clean one week with a flush of weeds the next. Sometimes it then rains, delaying post-applications. Dry conditions created difficulty getting pre-herbicides activated, allowing some weed escapes. Depending on the product, soil conditions, weather conditions, Dr. Stevan Knezevic shared that pre-products can last anywhere from 4-8 weeks. Page 24 of the 2020 Weed Guide also provides guidance on potential residual (also known as persistence in the soil) of herbicides if you’d like to check that out.
Bagworms: I haven’t spent time looking at evergreen trees to see if bagworm larvae
have emerged yet or not. If you have last year’s bags on your trees that are sealed (don’t have an open hole at the top), you can pick off some bags, place them in a ziplock bag, and place it outdoors on the south side of your house. When you see larvae emerge, it’s a good indication to start checking your trees in the next weeks. Each bag can hold 500-1000 eggs. The larvae are really small and hard to see. Stand still and watch the tree. If bagworm larvae are present, you will see very tiny movements as they begin the process of building new bags. I have pictures and a video at: https://jenreesources.com/2015/06/27/bagworms-in-evergreens/. Egg hatch is from mid-May to early June, depending on the year. Some caterpillar larvae remain on the same trees containing the bags from which they hatched. Others are blown by the wind to area trees allowing for new infestations to occur. For homeowners with small trees or only a few trees, bags can be picked from trees now and drown in soapy water or burned. In the summer, they can be squished, drowned, or burned. I have a great memory of visiting Grandma in the care center with my family. Grandma was concerned about the spruce in the courtyard. Seeing bagworms, I turned it into a science lesson for my nieces/nephews. They had a blast making quick work of picking off bags and squishing them to the delight/disgust of the residents watching (and their parents) 🙂 That’s not feasible for most situations though. We recommend waiting to treat trees until bags reach around 1/2” in size to ensure egg hatch is complete. Good coverage is needed when treating trees. With ground sprayers, we say to spray to the point of runoff. Bt products are effective early on. Most often I recommend a permethrin or bifenthrin product. Aerial application may also be an option for windbreaks. For more info., please see: https://go.unl.edu/rgju.
Congratulations to all who graduated from college or high school the past few weeks! You’ve experienced much challenge, change, and loss. Good can come from difficulty! May this experience better equip you for the future! Also wish to congratulate and welcome three new team members to the York and Seward county offices! Tanya Crawford will begin as the 4-H Educator in York County May 18. Emily Hemphill began as the 4-H Assistant in Seward County May 1. Kara Kohel will begin as the new Learning Child Educator in Seward County June 1.
Crop Update: Grateful for the recovery experienced on many frost/freeze damaged crops throughout the State! The worst damage I saw on corn in this part of the State resulted in exposed leaf tissue dying with new growth coming out of the ground within 5 days. Soybeans fared well in the area to which I’m extra grateful with the large number of early planted soybean acres this year!
There’s been some talk about uneven emergence in some fields. Most really aren’t too bad, just worse in fields that were worked or extra cloddy. And most often, seedlings are still coming when digging in the gaps. They’re just behind most likely due to depth or soil moisture variation. You may also want to check out an article on Early Season Insects in this week’s CropWatch at cropwatch.unl.edu. Also seeing and hearing of ammonia burn to roots of corn seedlings, mostly in strip till situations, due to the dry conditions. An inch or two of rainfall or irrigation can help dilute the salt concentration in the root zone and allow for growth of roots to resume. I realize this doesn’t help those without irrigation and we keep praying for rain. In a 2009 trial at UNL South Central Ag Lab near Clay Center, Dr. Richard Ferguson documented those plants being shorter in stature and appearing to have a purple color early in the growing season before later recovering.
For those asking about replanting, we have two articles to aid in decision making in this week’s CropWatch at cropwatch.unl.edu. I haven’t seen situations warranting this around here yet. It takes quite a stand loss. For example in corn, if there are 25,000 plants per acre and the field was initially planted on April 27 and you cannot replant until May 20, it would be better to leave your present stand, which has 95% yield potential, than to replant on May 20 when the yield potential for a stand of 30,000 would be 86%. Make sure you consider replant costs in your decision. Next week I’ll address thoughts on post applications to crops.
Lawn Update: As lawns grow, it’s important to not remove more than 1/3 of the height. During the spring and fall, cool season grasses such as bluegrass and fescue are also building their root reserves. Removing too much growth at once or continually mowing shorter than 3” puts more stress on the plant and doesn’t allow for as deep of roots for when the summer heat comes. UNL turf research found that lawns actually grow faster when they are scalped than when they are mowed at a taller height. So, if your lawn gets away from you like mine did last week, do your lawn a favor and raise your mowing height that one time and then go back to mowing at 3”.
Youth Learning Opportunities: There are a number of virtual and self-paced fun, learning opportunities for youth and families upcoming in the month of June! Many of the activities that were provided during the school year will be continuing with new sessions. You can check them all out at: https://4h.unl.edu/virtual-home-learning.
Building Better Babysitters Virtual Training: Additional childcare may be needed this summer. Babysitting is a big responsibility and it’s not for everyone. Youth ages 11 and up who are interested in building skills as a babysitter may be interested Nebraska Extension’s state-wide virtual babysitting training. Register by going to https://cvent.me/d4gWeD.
Adding some pics on frost recovery:
The anticipated cool temps and potential for frost damage were on the minds of several towards the end of last week. The warm spring planting conditions allowed for more soybean emerged in Nebraska and the mid-west than I’ve ever seen before at this time-frame. From UNL small plot and on-farm research, it’s warm springs such as this that have provided the larger yield increases when soybean was planted early. As I’m writing this, low temperatures varied throughout the State Saturday night with more anticipated lows tonight. What should one look for in regards to frost/freeze recovery? First, we’d say to wait 3-5 days post frost to look for signs of regrowth. It may take up to 7 days depending on weather conditions following a frost event. I’ve provided photos in my blog at jenreesources.com to aid in what to watch for and will continue to add photos. Have learned a lot by flagging plants at different growth stages and taking pictures of their recovery. Would encourage you to do the same. One thing we’re always provided is the opportunity to learn!
Survival partly depends on how low temperatures got. Air temperatures of 28°F or less for at least two hours may result in damaged tissue and even death if the growing point is affected in corn and soybean. Air temperatures around 32°F typically don’t result in freeze of plant tissues. Why is this? Plant cells have solutes in the cytoplasm and just outside the cell membrane that act like a modest anti-freeze. Thus, the actual tissue temperature has to reach 28-30°F for frost damage to occur.
It also depends on stage of growth. For emerged corn, the growing point is still in the ground. Frost damage can appear as leaves discoloring and wilting due to plant cells rupturing. Eventually they will turn brown and slough off if new growth pushes through. It will be important to look at the growing point and make sure it’s white/yellow and firm and not discolored and soft. Warmer temps after frost event will help in reducing disease impacts from bacterial pathogens.
Soybeans that are just emerging with the hypocotyl hook exposed at or just above ground level, can be the most at risk for damage. The hypotcotyl hook is the area of the stem below the soybean cotyledon. Anything that impacts it will result in seedling death. Watch for plants that have soft, mushy, or pinched hypocotyls. These are situations where soybean seedlings tend to die. I’ve seen survival in seedlings with light scarring on the hypocotyl and cotyledons where there’s no pinching of the hypocotyl. Cotyledons just at the soil surface or above often will survive due to their high water content. They may have some light scarring yet they tend to survive. Look for the plumule (first true leaves from the shoot) within 7 days post-frost to ensure the growing point wasn’t injured. If unifoliolates were exposed, I’ve seen mixed results (depending on air temperatures and location in the field). Sometimes the unifoliolates will wilt and die but if the axiliary buds by cotyledons survive, new growth will occur.
For wheat, look for any splitting of the stems near the base of plants. Make sure the growing point looks healthy. Damage to wheat in jointing stage occur at 24°F for 2 hours and 28°F for 2 hours at boot. Impacts to wheat later on can also be seen at heading in white awns and spikelets and heads sometimes having difficulty to emerge from the boot (or being twisted). This CropWatch article shares more.
Low areas of fields, fields with coarser soil texture, and lower soil moisture contents can result in more frost damage. Fields receiving rains and wind prior to these cold temperatures may have aided in some protection. There’s often things I can’t explain when assessing frost damage. Sometimes a couple plants in a row will succumb while others around them at the same growth stage are fine. There’s just microclimate things that can’t always be explained. Here’s hoping most fields in the area are ok!
It’s also time to scout for alfalfa weevils and you can see more information and table of thresholds depending on growth stage in this CropWatch article: https://go.unl.edu/a7jw.
Rhubarb and Frost: If rhubarb leaves are not damaged too much and the stalks remain firm, it is still safe to eat. If the leaves are severely damaged or the stalks become soft or mushy, do not eat these stalks. Remove and discard them. New stalks can be harvested and eaten.
Planting season has rolled on this year with large planting progress made in short time! I’m grateful for the general warming trend with no cold snaps unlike so many recent years. Like many of you, am also praying for rain. For pre- herbicides, it is important to have 0.5-0.75” of moisture within a week of applying them for activation. That was a topic of concern I was hearing from both growers and ag industry last week, thus why it was recommended that some start pivots. I’m starting to see grass and broadleaf weeds coming through on ground that didn’t receive moisture to get the herbicide activated. Corn and soybean are also emerging fairly quickly with these warmer temps. The latest in pheromone trapping cutworm counts across the State can be found at: https://go.unl.edu/jdd3.
Some have asked about interseeding covers into early vegetative corn or soybean. Perhaps the three biggest things we’ve learned are to make sure the seed is in the ground vs. broadcast, plan to seed between V2-V5, and think about your herbicide program before trying this. An easy to understand site for herbicide impacts to covers is at: http://interseedingcovers.com/herbicide-options/. That whole website holds good information. There’s an Upper Big Blue NRD soil health project with partners of The Nature Conservancy, NRCS, and Extension where we will have 6 on-farm research studies and several other demos of interseeding this year. Growers are looking at impacts of different mixes, corn populations, row direction, and number of rows interseeded (1 vs. 3) between the corn rows. Looking forward to these additional studies to add to the research base which we talked about in this CropWatch article last year: https://go.unl.edu/4nh7.
My prayers go out to livestock and poultry producers; I just can’t imagine. There are a number of resources at https://animalscience.unl.edu/swine for emergency depopulation of livestock facilities. Such a hard time all around in ag. Free farm finance and legal clinics for May can be found at: https://go.unl.edu/joos. Nebraska Farm Hotline/Rural Response Hotline: 800-464-0258.
Evergreen Tree Diseases: The wet springs the past several years have led to an increase of needle blights. Spring is the time to be spraying trees with preventive fungicides with timing depending on the disease. None of the options I list are exhaustive and not meant as endorsement. For windbreak situations of cedars and pines, some ag retailers have carried Tenn-Cop 5E or Camelot. For home-owner use for trees in landscapes, I will share what I’ve seen sold in our local stores. It’s important to read the product label to ensure it’s safe to use on the specific plant/tree you wish to treat as some copper products can harm plants. In Austrian and Ponderosa pines, tip blight (where tips die) and dothistroma needle blight (where needles turn brown and die) can be prevented with fungicide applications. Tip blight is best prevented in late April-early May with active ingredients of Propiconazole (found in Fertiloam liquid systemic fungicide), Copper Salts of Fatty & Rosin Acids (sometimes listed as copper soap such as Bonide liquid copper fungicide and other liquid copper formulations), or Bordeaux mixture. Dothistroma needle blight can be prevented in mid-May and a second application in mid-June with Copper salts of fatty and rosin acids and Bordeaux mixture. In spruces, needle cast can cause the yellow to reddish brown color of needles in the fall that remain that way in the spring. Fungicide should be applied when the new growth is half grown with a second application 3-4 weeks later. If your tree is severely infected, it may take applications like this for 2-3 years in a row. Chlorothalonil (found in Daconil and Fung-onil) is commonly recommended. Fungicides containing azoxystrobin, mancozeb, propiconazole, copper salts of fatty acids, and copper hydroxide are also effective at controlling this disease if the product is labeled for use on spruce. You can learn more about evergreen diseases, how to identify them, and more products for management at: https://go.unl.edu/rbcc.
It’s too early for bagworm control. I’ll share more on what to look for next week.
Crabgrass Preventer: Warm season annual grasses such as crabgrass and foxtail germinate when soil temperature at the 0-2” depth is consistently between 60-70F. Thus, we often say that reasonably, crabgrass preventer can be applied when soil temps at the 0-2” depth are consistently around 55F. Our CropWatch soil temperatures are measured at a 0-4” depth (https://cropwatch.unl.edu/soiltemperature). Based on them, it may be time to apply or at least getting close in the York area. If you’d like to determine the soil temp of your site locally, you can use a temperature probe or a meat thermometer (that you won’t use for cooking). Make a mark at 2” from the base and it will give you an idea. Remember to blow off or sweep lawn clippings and fertilizer from the sidewalks back onto lawns!
Moths: Our Extension entomologists are also starting to see black cutworm, variegated cutworm, and true armyworm moths in pheromone traps throughout Nebraska. You can see pictures and the counts (which will be updated) in CropWatch at https://go.unl.edu/jdd3.
Planting Green: Been receiving a number of questions throughout the state on this. We wrote a planting green article for CropWatch this week https://go.unl.edu/ysyi. We have minimal research but in the article, we explain more regarding herbicide considerations, what the research shows regarding allelopathy, and considerations based on growers’ and our observations and experiences. We haven’t found any wheat stem maggot flies in rye yet in Clay, York, or Seward counties. The flies we’re getting questions on are small brown flies and also seed corn maggot flies. Having an insecticide seed treatment on corn and beans will help against seed corn maggots. More info. from Iowa State: https://crops.extension.iastate.edu/cropnews/2020/04/seedcorn-maggots-flying-iowa
Seed Treatments for SDS: Continuing from last week, the summary is that ILeVO is an effective seed treatment in fields with high sudden death syndrome (SDS) pressure. However, not all areas of the field have the same amount of pressure, making it difficult to justify the cost field-wide. Three Nebraska on-farm research studies were conducted in soybeans in 2017 with a multi-hybrid planter. Soybeans with a farmer’s choice base seed treatment (check) were compared to the base seed treatment plus ILeVO. The goal was to look at site-specific application of ILeVO to reduce input costs while still effectively managing sudden death syndrome (SDS) pressure. Management zones were created using historical yield maps to show which zones were conducive to SDS pressure (SDS zone) and which weren’t (standard zone). Check strips and ILeVO treated strips were compared in both zones. Two of the locations showed no difference between the base treatment and base treatment + ILeVO in the SDS or the standard zones. At one location, SDS was not present in the field. In the other, the ILeVO treatment had significantly lower disease levels than the standard treatment and overall disease incidence was considered low. At the third site, the standard + ILeVO treatment yielded higher than the standard treated seed in the SDS zone. There was no difference in treatments in the standard zone. The SDS zone was around 50 acres and along a creek that ran through the field (Figure 1). Additional ILeVO studies were conducted in 2015-2016 via on-farm research in Dodge, Clay, and Nemaha Counties where an untreated check, base seed treatment, and base + ILeVO were compared. SDS incidence ratings were taken in addition to soybean cyst nematode samples. In two of the six fields, there was a yield difference between the base + ILeVO and other treatments, even though disease incidence was low. Two sites also had a significant decrease in SDS pressure with the ILeVO treatment, but it didn’t correlate in increased yield. These studies found ILeVO to be effective in reducing SDS pressure, but yield response and profitability depends on disease development and how widespread in the field. SDS pressure was found to be higher in frequently ponded soils or areas of the field with creeks or intermittent streams. We have no on-farm research data on Saltro although we have a York Co. study on it this year.
Freeze Events: With last week’s cold spell, it’s hard to know exactly how it will impact flowering trees, shrubs, and fruit trees. It really depends on the bud/flowering stage at the time of the freezing temperatures. I’ve also received a number of questions regarding wheat and how bad it looks due to frost right now. In some cases, the injury may look worse due to leaf burn from fertilizer and/or fertilizer + herbicide applications shortly before the freeze events. We need to be patient and allow time with anticipated warmer temps to watch recovery. Ultimately, wheat in the tillering stage is quite tolerant of frost with minimal yield impact expected down to 12F for 2 hours. Once the wheat begins jointing (growing point moves above ground), temperatures like what we experienced of 24F for 2 hours can moderately to significantly impact yield. While upper leaves may be burned off from frost, there’s actually a micro-climate effect within the wheat canopy which is warmer closer to the ground (depending on the wheat stand). If the soil had quite a bit of moisture prior to freeze events, it also helps buffer the soil temperatures, reducing freeze injury. What I look at: is the wheat in tillering or jointing stage? Do you notice any splitting of tillers at the base of the plants? If the wheat is jointing, split the stem to look at the growing point (I use a box cutter for wheat this small). Is the growing point white and healthy or yellow/brown and mushy? Wheat can tolerate much, but I can also appreciate how many of you are trying to make decisions. You can also check out the freeze to wheat article in CropWatch and more localized to our area, Nathan Mueller’s blog: http://croptechcafe.org/multiple-spring-freeze-events-impact-winter-wheat/.
Regarding alfalfa, it’s another ‘wait and see’ situation. Please see this week’s CropWatch
at cropwatch.unl.edu for more info. The more growth actually results in potential for increased damage and it also depends on the air temperature and duration of freeze. New seedlings can be pretty resilient due to being close to warm soil, protected by companion crops like oats, or due to natural seedling tolerance. Damage can range from upper stems and leaves wilting and turning brown to a hard freeze causing plants to completely wilt down and fall over. What I watch for are new buds…buds that are within the canopy that weren’t exposed to frost, new axillary buds that develop from upper stems that have frozen off, and new crown buds. In 2007, some chose to remove the dead plant material from the plants to stimulate growth. Dr. Bruce Anderson found the plants reacted to the killed tops from frost the same as they would from a normal cutting. Thus, we’d recommend observing how the alfalfa responds and ultimately doing nothing for the time being. Cutting alfalfa for hay with only 6” of growth in most fields wouldn’t be practical and can weaken plants. Anticipate first cutting to be delayed as a result of these multiple freeze events.
Planting: While you might not share this sentiment, I was grateful last week was so clearly not the right conditions to plant for this area of the State! It seems extra tempting when there’s a couple of really nice days prior to a cold snap. Outside of ‘is it ok to plant’ or ‘should I plant corn or beans’, my main planting question is regarding soybean seeding rates. We now have 13 years of on-farm research from this part of the State in 15” (planted not drilled) and 30” rows in silt loam/clay loam soils showing no yield benefit to planting greater than 120,000 seeds/acre. These studies included a seed treatment when soybean was planted in late April/early May. Otherwise, no yield differences were achieved from 120K to 180K regardless if seed treatment was used. We share more in this week’s CropWatch. With sudden death syndrome being bad in 2019, I’ve also received questions on seed treatments such as Ilevo® or Saltro® for it. I will share the research next week. Bottom line: economically I would only consider this if you have a history of SDS. Even so, environmental conditions don’t always favor SDS. You could consider using SDS treated seed along areas with a creek or intermittent stream running through the field or lower areas of the field where water ponds and using non-SDS treated seed in the rest of the field. Early planting doesn’t automatically favor SDS. Water during flowering and levels of soybean cyst nematode can favor it. Will share the data next week. And, a reminder to check your seed tag regarding proper PPE to wear when handling any treated seed. Here’s wishing you a safe planting season!
Happy Easter! This will truly be one to remember and hope you were able to still connect with family and friends in some way. For fruit trees and freeze temp. thresholds, please check out this resource: https://www.canr.msu.edu/uploads/files/PictureTableofFruitFreezeDamageThresholds.pdf. With planting having started for some or anticipated in the next few weeks, wanted to share some things I’ve been thinking about and some questions I’ve received.
As much as we have more physical distance in ag, it may be wise to have some plans in place in the event someone becomes sick with COVID-19 in your crop or livestock operation. Things such as disinfecting equipment and a sample 0-2 month plan with contact phone numbers are available in this week’s CropWatch at cropwatch.unl.edu. There’s also information on the CARES Act explaining the numbers. A series of Farm/Ranch COVID-19 free economic webinars are upcoming from UNL AgEcon. The first is this Thurs. April 16th at 3 p.m. CST. and features Nathan Kauffman, with the Federal Reserve Bank of Kansas City, presenting on COVID-19 Economic Developments and U.S. Agriculture. Details and recordings will be posted at https://go.unl.edu/manage2020.
Planting Considerations: It was nice to see equipment out in fields this past week! With tight economics, it’s important to make wise decisions with the factors we can control during planting season; it sets the stage for the rest of the year. One factor to consider is planting windows instead of planting dates. While this week is mid-April, it may not provide the best opportunities for planting. Be sure to check soil temps and plant at proper depth, not mudding in seed, and plant as close to 50F soil temps as possible when there’s a warming trend. Avoid planting when there’s potential for a cold rain/cold snap within 48 hours for corn and at least 24 hours for soybean. It’s also best to get seed in the ground 1.5-2” deep. For corn, this is critical in helping with nodal root establishment. For soybean, this aids in buffered soil moisture and temperature and helps delay emergence to aid against potential frost. Numerous research studies have proven the yield benefit to early planted soybean. Outside of the genetics, it’s the top way to improve soybean yields. When we conducted these studies via on-farm research, we also had planting date X planting rate studies. Those studies showed no yield difference when planting 120K vs. 180K in April vs. May beans. All the planting date studies had an insecticide + fungicide seed treatment and I have no data without it. Our soybean planting rate studies did not always have a seed treatment and now 13 years of that data still shows 90-120K planted seeds being the most economical while 120K is what we’d recommend for yield.
In this week’s CropWatch, I wrote an article with Jim Specht on soybean germination. The imbibition phase (water uptake) is the critical phase for potential seed chilling. Once the imbibition phase is complete, the soybean going through the osmotic phase can tolerate 35-40F soil temps as long as soil is not saturated. The reason why we say at least 24 hours for soybean vs. 48 hours for corn (regarding cold snap/cold rain) is because the soybean seed imbibes water much faster than corn. You can prove this to yourself! Put a soybean seed and corn seed in water and watch what happens. When teaching youth ag literacy, I put soybean seeds in water to show them the seed coat, root and first leaves. Granted, we’re not planting soybean into water, but it helps one see the difference in how the seeds imbibe water. Studies from journal articles showed the imbibition phase could complete in as little as 8-12 hours. However, it all depends on the beginning soil moisture, soil temperature, quality of the seed (no nicks in the seed coat, free of wrinkles from wet/dry cycles, higher seed moisture of 13-16%). There have also been experiments to suggest that soybean can be planted in 45F soil temps if soil moisture is stable and no cold rains occur during the imbibition period.
I’ve also received a few questions regarding rye rapidly growing and what to do. I have no research-only observation and talking to others. I’m still a fan of planting green. However, have noticed difficulty with residual herbicides applied to tall rye (above 12”) and getting down to the soil, thus weed escapes. So, a few thoughts. If you’re concerned about the rye, you can always terminate a few weeks before planting. Otherwise, consider splitting your residual with half on when you kill rye after planting with other half later or putting on your residual in a second pass after killing rye. Would welcome others’ thoughts/experiences of what’s working for you!
Dicamba Webinar: The National Ag Law Center is hosting a free webinar titled ‘The Deal with Dicamba: An Overview of Dicamba-Related Litigation’ on April 15th at 11 a.m. CST. It will discuss various lawsuits filed in response to crop damage allegedly caused by herbicides containing dicamba. Details: https://bit.ly/3e2LvGX.
Youth/Family Support: Last week I shared this link for many hands-on learning activities: https://4h.unl.edu/virtual-home-learning. Two more resources that may be helpful for families right now: Helping Children Cope with stress and change: https://child.unl.edu/helping-children-cope and Reading for Resilience which helps children cope with storybooks: https://child.unl.edu/read4resilience.
Checking grain bins: A local farmer suggested to share a reminder to keep checking on grain with temps warming up and much grain in storage. It’s also so important to be safe with grain handling. The following is from Dr. Ken Hellevang with North Dakota State University (full article at: https://www.ag.ndsu.edu/news/newsreleases/2020/march-23-2020/proper-spring-grain-drying-and-storage-critical). “The stored grain temperature increases in the spring not only due to an increase in outdoor temperatures but also due to solar heat gain on the bin. Solar energy produces more than twice as much heat gain on the south wall of a bin in spring as it does during the summer.
Hellevang recommends periodically running aeration fans to keep the grain temperature near or below 30 degrees until the grain is dried if it exceeds recommended storage moisture contents, and below 40 degrees as long as possible during spring and early summer if the grain is dry. Night air temperatures are near or below 30 degrees in April and 40 degrees in May. Soybean oil quality may be affected in less than four months if even 12% moisture soybeans are stored at 70 degrees.
Cover the fan when it is not operating to prevent warm air from blowing into the bin and heating the stored grain. Hellevang also recommends ventilating the top of the bin to remove the solar heat gain that warms the grain. Provide air inlets near the eaves and exhausts near the peak or use a roof exhaust fan… Grain temperature should be checked every two weeks during the spring and summer. Grain also should be examined for insect infestations. Check the moisture content of stored grain to determine if it needs to be dried. Remember to verify that the moisture content measured by the meter has been adjusted for grain temperature.
Corn needs to be dried to 13% to 14% moisture for summer storage to prevent spoilage. Soybeans should be dried to 11% to 12%, wheat to 13%. The allowable storage time for 13% moisture soybeans is less than 100 days at 70 degrees. Corn – For natural air-drying, assure that the fan’s airflow rate is at least 1 cubic foot per minute per bushel (cfm/bu) and the initial corn moisture does not exceed 21%. Start the fan when the outdoor temperature averages about 40 degrees. Soybeans – Use an airflow rate of at least 1 cfm/bu to natural air-dry up to 15% to 16% moisture soybeans. Start the fan when the outdoor temperature averages about 40 degrees.”
Burndown and pre-plant herbicide apps: Anticipating this week’s nicer weather, I’ve also received several questions on burndown and pre-plant herbicide applications and weather impacts on control. Dr. Amit Jhala wrote two articles in this week’s UNL CropWatch at https://cropwatch.unl.edu. Sunny days with temperatures above 40F for day and night, and even better when temps are climbing to the upper 50s and above provide better control than if it’s cooler than 40F. Glyphosate works faster during sunny conditions when it is 60-75F and remains there a few hours. The articles also list rain-fast period and planting interval restrictions (as would the product labels). If you’re looking for a general idea on potential residual activity of herbicides for overlapping residual, check out pages 23-24 of the 2020 Guide for Weed Management.
My colleague Dr. Nathan Mueller shared in his blog: http://croptechcafe.org/should-you-control-winter-annual-weeds-early/, “A 2007-2009 UNL study conducted in Lincoln and Clay Center found that in 5 of the 6 site-years (2 site per year for 3 years is 6 site-year) that not controlling winter annual weeds prior to corn and soybean planting resulted in greater than a 5% yield loss and a 10% loss in 4 of the 6 site years.”
As I write this, I’m setting outside on a beautiful sunshiny afternoon! It’s been so cool to see families spending time outside together doing lawn work, playing, or eating. Some have commented it’s nice not to be torn so many directions. There’s way more people walking than I’ve seen in the past. And, several groups have found ways to help such as sewing masks for medical staff and donating various items. Those are just a few good things I’m observing right now! There’s been a variety of questions Extension is receiving as a result of COVID-19, so this column will share resources to help.
Trusted Information: While the ability to access information can be good, the overabundance of mis-information can make this time challenging. When it comes to COVID-19, we recommend obtaining information from sources such as CDC, WHO, and locally the UNMC and health departments. As you see info from various sources, be aware photos and videos are being doctored and also check the date. Before sharing, right click on a link to see where the source is coming from. Does it end in ‘.gov, .edu, .com, .net, or .org’? Those extensions tend to be more trusted than other strange endings.
Food Preparation: There’s been a renewed interest in baking bread, canning and freezing! Food.unl.edu and in particular, this website, https://food.unl.edu/article/family-food-fun-home has a number of resources based on specific questions. When prepping fruits and vegetables, it’s really important that you do not use bleach, soaps, or hand sanitizing wipes on them! These products were not designed for food and can make you sick. Wash all produce thoroughly under only running water before eating, cutting or cooking. Your hands should be properly washed with soap and water when preparing food.
Youth Learning Activities: Finding yourself needing some fun activities for your kids during this time of being at home? A number of fun, hands-on learning activities are available at the https://4h.unl.edu/virtual-home-learning website! You will see activities for youth of all ages that provide both live, recorded, and self-paced learning.
Gardening: There’s also been a renewed interest in growing gardens. A great resource developed by Gary Zoubek is the vegetable planting guide on when to plant found at: https://go.unl.edu/d7qk.
Windbreak Renovation: Continuing from last week, there’s just too much information for me to cover adequately in my news column. Instead, we have several wonderful resources and wish to point you to them! We can also provide them for you if you don’t have internet access. They contain drawings of windbreaks and photos regarding do’s and don’ts.
- Windbreak Establishment: https://nfs.unl.edu/publications/downloads/ec1764.pdf
- Windbreak Renovation: http://extensionpublications.unl.edu/assets/pdf/ec1777.pdf
- Windbreaks and Wildlife: http://extensionpublications.unl.edu/assets/pdf/ec1771.pdf
- Windbreaks for Rural Living: https://nfs.unl.edu/documents/windbreakruralliving.pdf
Recertification Information: We’ve also received a number of questions regarding pesticide, chemigation, and dicamba certification. All in person classes have been cancelled and certification can be achieved online. We realize not everyone has access to computers or good connectivity. For private applicators who are in that situation, you can also call the pesticide office 402-472-1632 and they will mail you a lesson with test to complete instead. There is no option like that for chemigation or dicamba. We need to continue to be patient as information and rules keep changing. All certification information can be found at: https://pested.unl.edu/covid-19-information.
Happy Spring! With warmer weather forecasted the next few weeks, it’s a great time to get outdoors! Raking leaves from lawns is a great activity this time of year for the whole family. You can also overseed bare areas of lawns right now. Don’t remove leaves or mulch from landscape beds yet. Leaves and dead tops of plants protect the plants and keep them dormant as long as possible. Warm sunny weather causes plants to break dormancy early and they become more susceptible to cold temperatures. If you’ve already cleaned up landscape beds, be prepared to cover plants again in the event of cold weather. If you have frosted tulip/daffodil foliage like mine, just leave them be for now.
Even though grass is greening up, it’s too early to apply fertilizers (ideally not till sometime in May). Mowing isn’t needed until after the grass begins to grow and requires mowing. Then maintain a mowing height of 3 to 3.5″ season-long. Pre-emergence herbicides targeted at controlling crabgrass and other warm season annual weeds shouldn’t be applied until soil temperatures consistently reach 50°F. It’s still too early. Soil temps can be found at: https://cropwatch.unl.edu/tags/soil-temperature
Wild/Bur Cucumber: In wet seasons like last year, wild and bur cucumber were seen overtaking windbreaks. These are fast growing, warm season annual vines. They die each fall and come back from seed which germinate and begin growth typically in May. Vines can be cut at the base if there’s only a few of them this spring. Many asked about chemical treatments last year. A pre-emergent control option for large shelterbelts is Simazine (Princep 4L) to kill weed seeds as they germinate. Don’t apply more than 4 qt. Princep 4L per acre (4 lb. a.i./A) per calendar year. Don’t apply more than twice per calendar year.
Renovating Windbreaks: Do you have a windbreak that has several dead or dying trees in it? Steve Karloff and Jay Seaton, District Foresters, shared to think 15-20 years down the road. What would be your goals for the windbreak (wind/snow protection; bloom time; fruit, nut, wood; wildlife/pollinator habitat, etc.)? Each situation will be unique, so these tips won’t apply to each one. Determine whether you’d like to remove the entire existing windbreak or do a partial clearing over time. For those choosing a partial clearing, they suggest to consider leaving the north and west rows and removing the south and east side for sunlight, establishment, and protection purposes. Stumps can be left (unless Scotch or Austrian pine), or can be removed. A stump treatment listed in the UNL Weed Guide is 2 qts of low vol 2,4-D per 10 gallons of diesel. Apply to point of runoff. Don’t use Tordon especially if you’re cutting out and stump treating elm or hackberry trees that get intermingled in trees you wish to save as the Tordon can affect the roots of those trees too. If existing trees, such as pines, have been trimmed up due to dead branches but the remainder of the trees are ok, one could simply consider adding a row of shrubs to cut down on wind.
Also, think about diversifying species based on one’s goals to ensure the windbreak isn’t eliminated due to pest problems. That’s something we’ve unfortunately had to deal with regarding Scotch and Austrian pines due to pine wilt. Conifer specie options include: cedar (most hardy), Ponderosa pine, and Norway and blue spruce. Shrubs include viburnums and hazelnuts; however, there are numerous species to consider depending on goals. Consider 3-5 rows as optimal with 1-2 rows as conifers, 1 row of hardwoods or tall conifers, and 1-2 rows of dense shrubs. However, there’s not always that kind of room available and that may not fit one’s goals. It’s helpful to stagger plant the trees in each row and the gaps can be filled with shrubs or the shrubs can be planted in one row. Next week I’ll share more on site preparation considerations.