PRE Program……………………………………………………………No PRE Program
Sometimes a picture – or seeing something firsthand! – really is worth a thousand words. If you’re interested in seeing treatment differences in plots just like these conducted and evaluated each summer by the K-State Research & Extension Weed Science Team, check out a recent KSU Agronomy eUpdate article inviting you to take a look!
Almost a decade ago, a group of University of Nebraska Extension Educators collected moisture samples from 115 truckloads of soybeans . Close to 20% were below 10% moisture and almost 40% were below 11%. Maybe not a big deal – until you consider that 11 percent moisture soybeans represent a 3+% yield loss versus beans harvested at 13% moisture. We can’t harvest every acre at optimum moisture, but consider these ‘options’ to help a little:
There’s a lot to balance during harvest. Soybean harvest moisture is just one consideration, but it deserves at least a little attention to see how big of a factor it may be in maximizing soybean yield – and revenue.
This picture was taken this morning (09/13) of Fall Armyworm adults collected from a pheremone trap in EC JA Co. over the past 9 days:
It’s a good reminder to keep scouting. Brome has been a constant target, but monitor alfalfa and newly seeded cover crops as well. Young wheat/rye/brassicas/etc… all make great feeding for Fall Armyworm larvae and should be closely watched, particularly if growing conditions are slowed by dry weather.
Newly harvested alfalfa could be a potential feeding site as well. Because alfalfa typically has a more established root system it, it can handle some feeding, but vigilance is still encouraged. The last 4-6 weeks prior to a killing frost is important for alfalfa recovery going into dormancy (see the September 5th KSU Agronomy eUpdate article on end of season management here.). The chart below lists Fall Armyworm insecticides for alfalfa (full document here):
The Fall Armyworm Trap located in EC JA Co. continues to collect male moths – and reports keep trickling in about stand injury. What’s next? A few thoughts…
We have decent moisture and likely 6+ weeks of good growing conditions left for stands to make a comeback. Be vigilant, but be patient as well. The chart below shows how plants are affected when large amounts of leaf are removed:
Harvest is underway signifying both the conclusion of a growing season and the start of a very busy time for producers trying to get crops out of the field. Unfortunately, it can become a dangerous time as well…
At last night’s Fall Crops Meeting, K-State Research & Extension Environmental Quality Specialist presented a program he and Dr. DeAnn Presley have put together outlining carbon markets.
During his presentation, he shared this reference from the Illinois Sustainable Ag Partnership that outlines a number of the different programs being offered. If you want to know more about the ins and outs of various programs, check it out at: https://ilsustainableag.org/ecomarkets .
A couple of others to consider:
He also shared some questions a producer should ask before entering into a carbon contract. Some of them include:
These – and many other questions should be a part of your evaluation of any carbon credit program. These programs can be complicated and participation should be carefully considered to make sure it’s the right fit for you.
If you’re interested in the full presentation, e-mail me at dhallaue@ksu.edu.
With Tar Spot confirmed early this year, there were initial fears multiple pass fungicide applications might be needed. As summer progressed, however, Tar Spot didn’t take off as quickly as we first thought it might, allowing most fungicide applications to be delayed until our typical VT/R1 growth stages.
Recent weather events, however, may have added another disease to the mix to consider: Southern Rust.
This map is a great reminder of how diseases like Southern Rust arrive each year from the south – making their arrival difficult to predict. Guess no longer: Southern Rust MAY be in a field near you and that means continued scouting – or starting scouting again – is necessary.
There are two nice reads in the most recent KSU Agronomy eUpdate if you are a) still waiting to see if Tar Spot becomes an issue and b) if you’re concerned about Southern Rust. In them, K-State Research & Extension Row Crops Pathologist Dr. Rodrigo Onofre answers many of the common questions you’ll likely have about these two diseases, including:
TwoTar Spot blog posts below provide additional resources if you are interested – so I’ll add just a few things on Southern Rust to Dr. Onofre’s article:
Know What Disease You Have
There are other things that mimic Tar Spot. Insect feces are the major ‘copy cat’. For Southern Rust, Common Rust can be a confusing pathogen. A few differences in rust species (Common v. Southern) include:
Common Rust:
Southern Rust
Both rust fungi require only short periods of leaf wetness for infection – 6 hours of dew is usually enough – and mixed infections of both fungi can occur on the same plant.
Know What a Fungicide – Even One Previously Applied – Will Do
With any luck, a single fungicide pass will provide the protection needed against any/all fungal pathogens – but they don’t last indefinitely. If you’ve held off on a fungicide, scout now to determine if one is necessary (it may not be!). If you have already made a fungicide pass, scouting should restart 14-21 days post application as fungicide efficacy starts to wane.
How late can a fungicide work? While the R5 (dent) growth stage typically signals the end of any potential benefits of a fungicide application, it’s difficult to see much return on investment from applications even at R4 (dough stage – approximately 30 days post-silking). Applications from the late R2/R3 growth stages and beyond need to be carefully considered to evaluate the potential for a return on investment.
There are typically two times a year when we spend time looking down into our cool season hay fields: once when we apply fertilizer and again at harvest. The rest of the year, we tend to look across them, usually from a distance.
It’s not that ‘horizontal’ evaluations aren’t beneficial. We can see differences in heading and color. This year, some of those differences have been readily visible and it hasn’t taken a lot to note the variability across our stands. Take this picture for instance. There are a lot of differences in heading AND color taking place – in a very short distance:
So while a horizontal evaluation may be good, it may not tell the entire story, and that’s when a more ‘vertical’ evaluation might be in order.
Continue reading “Hay Stand Evaluations – Horizontally AND Vertically”
Two more (Kansas) counties were added to a growing list of Tar Spot confirmed areas across the Corn Belt. Jefferson and Nemaha Counties were added, as were neighboring counties in SE Nebraska (Richardson) and NW Missouri (Platte). To date, most disease pressure is very light, but scouting should continue (follow confirmations at: https://corn.ipmpipe.org/tarspot/)
What now? An excellent synopsis of the current situation is provided in this week’s KSU Agronomy eUpdate from K-State Research & Extension Row Crops Pathologist Dr. Rodrigo Onofre at: https://eupdate.agronomy.ksu.edu/article/update-tar-spot-is-now-active-in-four-counties-in-northeast-kansas-597-6 . It will provide answers to a lot of the questions you are likely mulling over as we prepare to make treatment decisions.
I would also add a couple of additional thoughts/references to consider…
Know What You Have
Some of the black spots on corn leaves are Tar Spot – but likely not all. In the early stages of the disease, bug droppings and other material have a similar appearance to Tar Spot but are not. Check by taking a small bit of moisture on your finger and trying to rub the spot off. Tar Spot will not rub off.
If in doubt, let us know! Images can e-mailed to me at dhallaue@ksu.edu or reach out via any Meadowlark Extension District Office for other submission methods, including The KSU Plant Pathology Lab. Submission can be made through the office or via the lab information included in the article above.
Fungicide Selection – How do I make the best decision?
In the post below is an image of a fungicide efficacy chart courtesy of the Crop Protection Network. It’s a great cross reference of products with efficacy ratings based on input from many of years of plant pathology expertise across the Corn Belt. Check it out before you make a fungicide decision.
When should I apply?
Dr. Onofre outlines suggested fungicide timings in his eUpdate article including a link to the KSU Corn Growth and Development Poster with this statement:
Research has shown that making an application just after first detection and at or after VT is effective if lesions are detected early. If you wait until there is significant disease in the upper canopy, a fungicide application may be too late.
Want additional information on application timing? This article from Dr. Mandy Bish at the University of Missouri is a good one: https://ipm.missouri.edu/croppest/2024/6/tar_spot-mb/?fbclid=IwZXh0bgNhZW0CMTEAAR1Veg8A-w90opxILQYOk5_GLw-dFxbF0AJ74fELPskmX9u8Xha2W-gb9mo_aem_ZmFrZWR1bW15MTZieXRlcw . She shares information from a study that separates application timing differences between seeing a yield response and seeing a return on investment to the application.
Keep in mind: you have +/- 12 days from silking (R1) to blister (R2) and by three weeks after silking you are at R3. That seems like a wide window – until it’s not. Plan accordingly!
Are Other Diseases a Concern?
They sure could be and fungicide application timing needs to be considered in light of pressure from those other diseases as well. Scouting will be important to stay ahead of damaging levels of Gray Leaf Spot, Common Rust, and Southern Rust as well – even if Tar Spot doesn’t become a huge issue. NOTE: as of this writing, Southern Rust has NOT yet been detected in the United State according to the Corn ipmPIPE page dedicated to Southern Rust.
Want to Dive Deeper?
Tar Spot continues it’s move and fungicide application decisions will soon be upon us. Feel free to reach out if you have any questions!
This is not a map you want to be first on – but here we are. On June 5, 2024, K-State Research & Extension Row Crops Pathologist Dr. Rodrigo Onofre confirmed the first Tar Spot finding of 2024 in corn fields in Doniphan and Atchison County Kansas. This is 3-4 weeks earlier than confirmation in 2023.
Interspersed below are Tar Spot resources to answer some common questions you might have about this challenging disease.
Is this early finding a surprise?
Maybe…but not totally… While this disease continues it’s spread south and west into Kansas, for NEK, even as the timing is earlier than preferred, it’s not completely unexpected. The Corn Belt area affected by Tar Spot has been increasing since 2018 (https://corn.ipmpipe.org/tarspot/historical-end-of-season-maps/) and in Kansas since confirmation in 2022. We now have established pathogen sources in corn residue across much of the NE part of the state allowing this disease to get a start as soon as conditions allow.
What are those conditions:
For some areas of the state, those were certainly the conditions in May…
What were the conditions surrounding THIS confirmation?
See more details in this afternoon’s KSU Agronomy eUpdate, but fields have had a history of Tar Spot. Previous crops were both corn and soybeans.
Should spray applications begin?
Scouting is always a best first option. While I do expect this to be an increasingly common corn pathogen, every field will be different (hybrid susceptibility + previous crop management both affect pressure…). Consider this advice from University of Wisconsin Field Crops Pathologist Damon Smith:
Confirmed levels right now are low. Unless scouting dictates otherwise, fungicide applications are not warranted at this time. Be aware of disease presence. Scout to determine levels in your fields. Plan ahead for fungicide applications should the need arise.
What products work – which don’t?
There are lots of good products available. One good reference is this report summarizing efficacy research from the Corn Disease Working Group, a consortium of Plant Pathologists from across the country. This excerpt shows ratings for specific diseases (a few Tar Spot ratings outlined in the vertical gray box at right). Efficacy ratings are outlined in the purple box at the top.
NOTE: four years of data from Darcy Telenko (Purdue) and others shows definite efficacy differences among products as well as multiple mode of action products vs. single mode of action products.
Where can I get additional information:
Feel free to drop me a line as well via any of our Meadowlark Extension District Offices (contact information at left) or e-mail to dhallaue@ksu.edu. I’ll be posting regular updates and additional information here as might be useful. Best of luck!
If you want a podcast that hits on traditional weed control topics (Herbicide Burndown in No-Till, Herbicide Carryover with Kevin Bradley, etc…) plus a few a little less than traditional (at least for our part of the country…) – A Conversation Between Plants and Weed Control in Mint for example… check out the War Against Weeds Podcast.
Put together by three Extension Weed Management Specialists, including K-State’s own Sarah Lancaster, this is a great podcast that hits on all things weed control. Check it out!
It’s still early in the corn growing season, but at some point – even through the end of the season – we might look at a stand and ask: why am I missing plants or why are some plants yellowing? Even worse: why didn’t this farm yield like we hoped or what caused this lodging? With the myriad of factors that could lead to any of these issues, it can be difficult to pinpoint just one. Complicating things is the amount about crown rots we just don’t understand.
One of the reasons we pay such close attention to soil temperature, utilize seed treatments and make sure we’re planting in good conditions is because of diseases like crown rots. Caused by pathogens including Fusarium, Rhizoctonia, Pythium, or others, these diseases can affect corn plants early in the season with symptoms only noticed until much later. Seed treatments can do an excellent job of combatting them, but when conditions are right for a specific disease to develop (temperature/moisture/seed treatment/etc…), problems can arise.
It’s always a bit of a tricky ‘balance’ when we get spring moisture like we did across NEK this week. We want (need…) it to help with emergence but if it leads to emergence issues (crusting, etc…), sometimes we’d just as soon the plant emerge before moisture arrives. If emergence is an issue, that usually means a deep dive into potential causes. Compaction, residue levels, cold stress, etc… all must be considered. So, too, does the possibility of a soybean seedling disease.
Most soybean seed is treated with a seed treatment that works well enough we often take them for granted. Still, understanding what that treatment is – and what it will combat – is an important part of diagnosing emergence issues when they are attributed to disease. For example, metalaxyl and mefenoxam have activity against diseases like Pythium or Phytophtora – but not Rhizoctonia or Fusarium.
Continue reading “Soybean Seed Treatments – Will They Work?”
This post is overdue but (hopefully…) signals the end of the alfalfa weevil season for most of NEK. KSU Extension Field Crops Entomologist Jeff Whitworth expressed to me multiple times this season his disdain for this pest. I’m increasingly in agreement as a second year of heavy pressure started early and caused way too much damage. This is an example:
The bad: that’s a lot of damage. The good: the leaves in the upper RH corner surround a pupal case, signifying feeding was likely wrapping up in the southern reaches of the District. This image was from earlier this week along the Nebraska line showing the same in the northern part of the District:
So while the season is winding down, remember: no two fields are the same! This graph shows two fields – neither receiving an insecticide – with increasing weevil levels in one field while numbers declined in the second. More on the multiple reasons why in a future post…
What about insecticide efficacy? I’m hearing mixed reports from growers and retailers alike with this graphic telling a little of the story (no data = sprayed):
The take home: some applications worked really well. Others worked, but maybe not quite as well! The reasons are numerous and I’ll try to share a little of what I’ve gleaned from observations this spring over the next few weeks in preparation for 2025. It underscores Dr. Whitworth’s continued reminder that this isn’t a complex insect – but that doesn’t make it easy to manage!
In my last post, I referenced how growing season weather can effect smooth brome production. Weather isn’t the only factor to consider, however. We know cool season forages respond to good fertility, but did you know there can be fertility/soil interactions as well?
This chart from the Kansas Grazingland Management handbook provides a look at how soil fertility and soil depth affect cool season grass production both independently and in combination with each other (based on animal carrying capacity). Note the differences in productivity based on depth of soil alone – and then how those same stands really thrive under good fertility.
Most of the time we have a pretty good idea of a site’s overall productivity based on management over time. However, if you’re ever working to enhance your grazing management system or troubleshooting a lack of production – a second look at a site’s soil type differences is a good idea. The USDA Websoil Survey (https://websoilsurvey.nrcs.usda.gov/app/ ) is a great place to start. Other grazing productivity sites might have some application as well. Drop me a line if you want to learn more about some of them at dhallaue@ksu.edu.
Smooth Bromegrass is the predominant species in most of our forage systems. It’s been shown to fit our growing season well and fertility management has allowed us to push production, particularly in some of our deeper soils.
But it’s not perfect. Fertility needs have increased. It likes moisture, and season of use must be understood so we can best manage it for the current season and beyond. We can’t do much yet this season about some of brome’s needs, but an understanding of season of use can still be valuable.
In a post below, buckbrush management is highlighted. A second multi-stemmed species of concern for us in our perennial forage systems is Roughleaf Dogwood.
One of the challenges with a roughleaf dogwood control program is how much later it comes on than buckbrush. Buckbrush gets to its optimum control window earlier than dogwood, which often doesn’t exhibit its flat-topped clusters of white flowers until late May or early June. In native grass pastures with regular burning, fire can keep it from getting started (see some Konza Prairie control differences in this week’s First Friday Forage Focus on our Meadowlark Extension District Facebook page: https://www.facebook.com/Meadowlarkextensiondistrict ). In cool season forage stands, or unburned warm season prairies, dogwood becomes difficult to remove once established.
Overview:
As expected, weevil numbers continued their increase over the past week, with every site approaching – or passing – the 50% threshold we often look to for triggering treatment. In fact, multiple sites were sprayed prior to my visits this week and most sites will have seen an insecticide application by early next week.
Resources of interest:
• Treatment efficacy trial results can be found at (lower RH corner of the page): https://www.meadowlark.k-state.edu/crops-soils/index.html .
• Additional pest/production information can be found in the KSU Alfalfa Insect Management Guide: https://bookstore.ksre.ksu.edu/pubs/mf809.pdf
What’s Next?
With most sites likely sprayed over the next week, data next week will likely be limited. Many thanks to the cooperators who have allowed me to check fields and monitor feeding levels.
Scouting will resume post insecticide application to see how products performed – if evaluations can be done prior to the first cutting! In the meantime, drop me a line if you have any questions!
Here are the updated scouting numbers from this week:
The good news is: we DID see at least some small level of mortality from the freezing temperatures this week as the picture below shows. In some fields, there may have been as 5% of these.
The bad news is there are STILL plenty of small larvae still hatching out there. Most of the larvae are very early instars meaning the hatch is probably not over just yet… So, while we got rid of a few this last week, and feeding certainly slowed, there are still numbers to come we need to be on the lookout for. Most fields have yet to reach treatment threshold save for those in the very southern part of the District.
As we reach the 50% threshold often used for treatment, I wanted to reference the KSU Alfalfa Insect Management Guide: https://bookstore.ksre.ksu.edu/pubs/mf809.pdf . It does a nice job of providing active ingredients, rates, etc… As referenced last week, efficacy trials can be found in the lower RH corner of the page at: https://www.meadowlark.k-state.edu/crops-soils/index.html .
The first brush species we typically see in spring is an invasive species known as bush honeysuckle. It’s an issue, but not so much in pasture or rangeland. One that is an early season issue, however, is buckbrush (coralberry). This native perennial spreads mostly via runners, with plants eventually forming dense patches and shading out desirable forage species. Control will require multiple years, and maybe multiple approaches as well.
After reports last week of alfalfa weevil infestations in the southern part of the District, our ‘early’ spring was confirmed by the presence of hatched weevil across the area in scouting conducted this week.
Results:
Scouting was done in 9 fields this past week. In each field, I randomly cut 30-70 stems and tried to extract all the weevil I could out of each one. The infestation levels were as follows:
While we did see some level of mortality from the last cold snap, it was by no means extensive. At most, I found +/- 20% dead larvae among the live ones. In most instances, it was difficult to find even one.
Analysis:
Keep in mind a couple of things:
1. Typical ‘threshold’ is 50% or one larvae found/every two stems.
2. Most of these larvae are pretty small so feeding damage still appears fairly light in most cases Continue reading “Alfalfa Weevil Levels – 03/22/24”
It started a couple of weeks back on social media, but weather this week will increase the conversations even more: why wouldn’t I go ahead and put some beans in the ground?
Arguments can be made for and against early planting (another post for another day…), but what does seem consistent on both sides of the argument is: A soybean that emerges and begins to grow quickly generally tolerates disease/insect pressure better than one in cold, damp soils (if it survives – will it thrive?). Seed treatments are often used to help weather those cooler, damper conditions and while they do a great job, they have limitations. One is the active ingredient(s) in the treatment and what they will control. Another is the length of time they can provide some level of protection (approximately three weeks after planting give or take…)
One handy resource is Fungicide Efficacy for Control of Soybean Seedling Diseases from the Crop Protection Network. It provides some excellent information on various seedling diseases.
It also has some excellent information on seed treatments for a disease that infects the soybean plant early, but doesn’t show up until much later: Sudden Death Syndrome or SDS.
Increasingly an issue for NEK soybean growers over the past decade, SDS has shown the ability to survive not only soybean residue and in soil, but on corn residue as well. It survives our traditional rotations quite well and takes advantage of infection opportunities – most often when seedling development is slowed by cool/wet soil conditions. This graphic from K-State Extension Plant Pathologist Dr. Rodrigo Onofre illustrates some of those optimum infection windows:
While early planting does give us a better opportunity for SDS infection (that is when it’s typically cool and damp after all…), note that we often need a wet period later to trigger the infection symptoms. Its one of the features that makes SDS management difficult because we never know what we’re going to get from a weather standpoint – from infection all the way to visible symptomology.
Since we don’t know for sure what weather might throw at us, we often have to manage SDS in other ways. Start with the seed. Check varieties for SDS tolerance and use high germination seed when possible.
Good planting practices are also key. Research from the Kansas River Valley Experiment Field showed increased frequency of SDS foliar symptomology in narrow row spacings as compared to wider spacings.
Source: Dr. Rodrigo Onofre, K-State Extension Row Crops Pathologist
Because it’s a fungus, fungicide seed treatments have become popular as well. According to the previously referenced fungicide efficacy publication, there are multiple products labeled for SDS control. Unfortunately, many of the ones we might utilize for other diseases are rated poor for Sudden Death Syndrome – if they’re labeled at all. In fact, only two active ingredients – fluopyram and pydiflumetofen – are rated as very good for SDS control. Fluopyram is the active ingredient in ILEVO. Pydiflumetofen is the active ingredient in Saltro.
In 2023, K-State Extension Plant Pathologist Dr. Rodrigo Onofre tested both products in side-by-side comparisons with other seed treatments comparing all to an untreated check. While all seed treatments provide some positive yield difference, ILEVO and Saltro showed the strongest response.
Further evaluation by Onofre confirmed positive reductions in SDS root rot as well, either with Saltro by itself or ILEVO plus Ceramax, a biological seed treatment being tested with hopes of reducing the variability sometimes associated with seed treatments against SDS.
Soybean Sudden Death Syndrome isn’t a problem for every grower every year, tending to be a greater issue in well-managed soybean fields with a high yield potential, particularly when they have a history of SDS. In some cases, variety selection and planting management will keep SDS from being an issue, but if early planting or if planting conditions are favorable for SDS development, seed treatments could be an option to consider.
For more information on SDS management or K-State trials, contact me. Fungicide Efficacy for Control of Soybean Seedling Diseases are available upon request as well.
Alfalfa weevil growing degree days are accumulating fast! Come hear from KSU Field Crops Entomologist Dr. Jeff Whitworth as we discuss what to expect from some warm weather this winter plus hear results from product efficacy trials and application best management practices.
We’ll conclude the morning with a Q & A session open to questions about insects in any of our field crops.
RSVP is due March 4th. Hope you can make it!
This graphic from an Oklahoma State publication paints a good picture of the challenges a small business has when it comes to making transitions.
Agricultural enterprise transitions aren’t exactly the same as small businesses, but with statistics (Purdue) suggesting only 55 percent of farms have a written succession plan, it’s not difficult to see how successful transitions could be a challenge.
If you’re looking at a Farm Transition, check out the Farm and Ranch Transitions Conference March 8th in Manhattan. It will be a great day to learn more about farm transition planning from one of the best in the business: Dr. Shannon Ferrell, Ag Law Specialist at Oklahoma State University.
Registration closes March 1. Get signed up today!
Tis the season for prescribed burns – but there are a lot of questions we should probably be asking first!
Here’s an example of the conditions for Friday afternoon, February 23, 2024:
Continue reading “Conducting a Prescribed Burn – Are You Planning for Success?”
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