K-State Research and Extension

Emerging corn diseases over the past 3 seasons have increased pressure on budgets – and our management! Tar Spot was first, and while Corn Stunt confirmation in Kansas doesn’t guarantee it will be an issue, it does mean we need to be on the lookout.

To stay abreast of what we know, two Corn Disease Updates (Thursday, February 6th in Seneca & Friday February 7th in Oskaloosa) will cover what Corn Stunt means for disease management systems and share updates learned in 3 seasons of Tar Spot. Meetings will conclude with an overview of fungicide resistance management in soybean, an update on Soybean Gall Midge and a sponsored lunch. K-State Research & Extension Row Crops Pathologist Dr. Rodrigo Onofre will headline our Seneca meeting. Meadowlark Extension District Crops & Soils Agent David Hallauer and NE Area Agronomist Dr. Tina Sullivan will lead the discussion in Oskaloosa.

Information can be found in the graphics or the Meadowlark Extension District Events Page. Meal count numbers are requested by noon on Tuesday, February 4th. RSVP via any Meadowlark Extension District Office, e-mailing me or using the QR code below/online: https://tinyurl.com/corndisease.

In case of inclement weather, you will be contacted via your registration information. You can also monitor program status on the Meadowlark Extension District Crops & Soils page: https://www.meadowlark.k-state.edu/crops-soils/ or Events Page above.

Hope to see you there!

Try to think of one good thing that came from the couple of bitterly cold stretches we’ve had so far this winter…I know…it might be difficult…I’ll give you a minute! 😉

Agronomically, there might not be many. Could soils have gotten cold enough to initiate freeze-thaw cycles to help alleviate compaction? Possibly. Maybe a few insect pests froze, reducing next season’s feeding pressure? Not likely.

Continue reading “Sub-Freezing Temperatures and Insect Life” →

Most of the state’s agricultural producers lease land in some form or fashion. Each agreement is a little different, and that can sometimes lead to questions or even confusion. If you haven’t yet made at least a quick review of any ag lease arrangements you have in place, now would be a good time to do so. Continue reading “Reviewing Your Land Lease” →

The New Year often arrives with some reflection. Unfortunately, not everything in 2024 was a positive reflection, including another season of fall armyworm larvae feeding on bromegrass.

A trapping network instituted across the state in 2023 to monitor fall armyworm moth levels is still getting the bugs worked out (pun intended…) and took another step in 2024 with regular moth number reports. While not intended as a way to predict damage, it does paint an interesting picture of what moth numbers are doing during the growing season.

For example, moths pressure may have been higher earlier in the season than noticed. Traps were monitored weekly starting in mid-July with moths found the first week out. Numbers varied, but one location had moth captures in 17 of 18 weeks it was monitored. The second had months captured in 11 of the 15 weeks it was monitored. Early season trapping may not tell us a great deal (there’s generally ample forage for feeding without a lot of damage), but it is interesting to note there were likely already numbers present in mid-July. Continue reading “Moth Musings: Fall Armyworm Trapping Network Update” →

Somehow, I got added to the e-mail list of a fertilizer product company. Maybe it’s coincidence…maybe it’s not, but they must know my disdain for Broomsedge Bluestem, because the last few ads have been all about it!.

Some parts of the ad are sound: soil test regularly; weedy species tend to increase when soil fertility levels are outside of appropriate levels; and Broomsedge isn’t good for much. I can get on board with those.

Others…not so much, particularly when Extension/University research is shared inaccurately or out of context. Growers: buyer beware!

Continue reading “Fertilizer Product Claims…” →

Want a reminder of just how quickly grasslands can be taken over by woody species? Check out this graphic from The Prairie Project:

The Prairie Project collaboration (producers, University Extension, researchers, and others) is designed to share research on woody encroachment issues and other grazing topics – in hopes of keeping this map from getting any darker. Management to combat woody encroachment isn’t easy. Unfortunately, doing nothing will only result in continued acreage lost.

In the last month, we’ve published a number of news columns focused on some of the reasons these plants do so well in our environment (The Competitive Nature of Sericea Lespedeza), how to give cool season grasses a competitive advantage (Soil Sampling Tips – Hay/Pasture) as well as some ways to extend our brush management control efforts – often well into winter:

• Brush Control Using Basal Bark Treatments
• Brush Control Using Cut Stump Treatments
• ‘Other’ Brush Control Options

In addition to these articles, consider grabbing a copy of the 2024 KSU Chemical Weed Control Guide, available from any Meadowlark Extension District Office or online at:   In it, you’ll find helpful charts like this:

If you’re interested in soil testing, brush control, or just want a copy of our Chemical Weed Control Guide, drop me a line at dhallaue@ksu.edu .

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:

• Consider harvest at a higher moisture level – 14/15%. Soybeans are fully mature when 95% of the pods are a mature tan color, likely with leaves still on the plant. It will mean slower harvest speeds and combine adjustments throughout the day as conditions change, but if they can be done without costing too much time/money, they might help.
• Harvest under optimum conditions and when doing so may make it possible to capture overnight moisture. It can also help reduce shattering losses (4-5 beans per square foot = +/- 1 bushel/A loss.

• Remember: soybeans dry down faster than corn. Work by KSU Farming Systems Specialist Dr. Ignacio Ciampitti looked at the moisture content of soybeans during different growth stages, focusing on the dry down time from black layer to harvest. From late September through mid-October, the dry down rate (58 down to 12%) was +/- 3%/day, taking just 15 days in many cases. Temperature/humidity/water content at maturity all affect this dry down, but it often occurs more quickly than we think.

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…

• Continue Scouting: the southward migration of Fall Armyworm likely won’t occur for some time yet. Additional generations will be looking for tender growth to continue their life cycle and regrowing forages – brome recovering from previous feeding, recently harvested alfalfa, or even newly seeded cover crops – are prime targets.

• Evaluate Stands: with decent moisture across parts of NEK, stands should start to regrow – if other factors aren’t holding them back. If the stand was recently harvested, regrew a bit, and then was fed on, root system energy reserves may be depleted enough to result in slow recovery (see below) – or even stand loss. If you don’t see some recovery after 2-3 weeks, consider digging up plants to see if new growth has been initiated.

• Consider Options for Fall Seeding: with any luck, the stand will recover quickly and we’ll move on. If they do not, consider what you want to reseed and what the fall planting window for that forage may look like.

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…

Continue reading “Harvest Safety” →

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:

• How to Grow and Sell Carbon Credits in US Agriculture (Iowa State University): https://www.researchgate.net/publication/353523269_How_to_Grow_and_Sell_Carbon_Credits_in_US_Agriculture
• KSU Ag Economist radio interview: The Future of Carbon Markets –
  https://www.agmanager.info/news/future-carbon-markets

He also shared some questions a producer should ask before entering into a carbon contract. Some of them include:

• How do they measure carbon stored? Will they collect the initial and follow-up soil samples or do you? What is their fee to collect the samples?
• Understand the payments and the costs. Do they pay by acre or by carbon credit? What is the payment schedule? Some companies use holdbacks or a percent taken off of the top to cover their role in the process. What are their fees? Are they in line with other companies?
• Can you stack carbon market payments with cost-share payments from local or federal governments?

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:

• where either/both of these diseases been confirmed
• when/IF a fungicide should be applied
• how to choose a fungicide product

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:

• Pustules appear on upper AND lower leaf surfaces
• Typically brown/brownish red, elongated, and scattered on leaf surfaces
• Prefers cooler weather (61-77°F)
• Takes heavy disease pressure to cause losses (Wisconsin estimates indicate it takes 162 common rust pustules/leaf to reach 1 percent severity).

Southern Rust

• Pustules appear primarily on the upper leaf surface
• Orange to light brown, round, and densely packed on the leaf surface
• Prefers warmer weather (77-82°F.)
• Can reach heavy pressure levels quickly requiring vigilant scouting for making potential fungicide application decisions.

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?

• If you want a deeper look into some interesting work comparing early AND late fungicide applications, check out this recent video from Purdue’s Darcy Telenko: https://www.youtube.com/watch?v=qObD-ld9G88 .
• If product efficacy information is of interest, another video from the Crop Protection Network shares multiple years of efficacy information from the fungicide working group: https://www.youtube.com/watch?v=CI62h71g6qQ . The 2023 data starts at around the 20:00 mark.

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:

• 60-75 degree F temperatures
• > 7 hours of leaf wetness
• Irrigation

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:

• Fungicide Selection: Fungicide Efficacy for Control of Corn Foliar Diseases [PDF]
• For a deeper look into the disease: Crop Protection Network publication solely dedicated to Tar Spot: https://cropprotectionnetwork.s3.amazonaws.com/tar-spot-filename-2020-05-12-175731.pdf
• Regular Kansas based updates: the KSU Agronomy eUpdate includes a ton of information on numerous topics, and will be a great source of regular updates on the current conditions surrounding Tar Spot for us, including Kansas research results and observations from K-State Research & Extension Row Crops Pathologist Dr. Rodrigo Onofre. Find it here.
• Disease confirmation: suspicious about what you might have? samples are always welcome in the K-State Plant Disease Diagnostic Lab. Information on sampling and submission can be found at: https://www.plantpath.k-state.edu/extension/plant-disease-diagnostic-lab/

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.

Continue reading “Crown Rot Pathogens in Corn” →

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.

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.

Continue reading “Roughleaf Dogwood Management” →

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 .