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K-State Turf and Landscape Blog

Tag: herbicides

Planting Buffalograss and Controlling Weeds

By PhD student Dani McFadden, and Jack Fry, Professor and Commercial Turf Extension Specialist

Are you thinking about converting an area to buffalograss? It is a warm-season grass native to Kansas and much of the Midwest, with excellent heat, drought, and cold tolerance.  It is important to understand the characteristics of your site before determining if buffalograss is an adequate fit. Buffalograss grows best in an area receiving morning sun, and 6-8 hours of sunlight throughout each day. It is recommended to not plant buffalograss in poorly-drained areas or sandy soils. For non-irrigated sites, planting is recommended in the spring once soil temperatures reach 55 F. An optimum seeding rate is is 1.5 to 2 lbs of buffalograss burrs (1 to 5 seeds in a burr) per 1,000 sq. ft.

Buffalograss is dioecious, which means there are male and female plants.  In seeded areas, you can see the inflorescences (male flowers) on male plants  emerge several inches tall.  The female plant produces a flower close the soil and is not as noticeable.  Ultimately, several seeds are produced within the female burr. There are vegetative buffalograss cultivars that can be purchased which are most typically plugged for establishment.  They are generally the female plants (no visible seedheads during the growing season).

You can learn more about cultivars, establishment, and management by using these links:

K-State “Buffalograss Lawns”: https://bookstore.ksre.ksu.edu/pubs/mf658.pdf

K-State Turf and Landscape Blog:  https://blogs.k-state.edu/turf/

National Turf Evaluation Program:  https://ntep.org/

For irrigated sites, you can delay seeding until June through July; early June planting enhances the potential for good coverage by the end of the growing season. Seed should have good contact with the soil – planting 0.25 to 0.5 inches below the soil surface is recommended.  For effective grow-in, any non-desired vegetative grasses or weeds should be removed from the area with the use of herbicides (check label to confirm time required before seeding can be done after application).

Converting an area to buffalograss can be costly and time consuming; therefore, it is important to protect the area from weed invasion. Weed control is critical during establishment, as many weeds are able to outcompete buffalograss seedlings. Mesotrione (Tenacity) is labeled for application at the time of seeding. Quinclorac (Drive XLR8) is also labeled for application any time before or after seeding buffalograss for the postemergence control of grassy weeds. Two combination products, SquareOne and Solitare, are labeled for use on established buffalograss for the control of a broad spectrum of weeds. If you are facing weed pressure, it is important to first identify the weed before purchasing the herbicide. For example, products containing quinclorac as a single active ingredient will control many grassy weeds, with minimal control of broadleaf weeds. You should always read the herbicide label for a detailed list of weeds controlled by the product, along with application rates and timings.

 

Japanese Beetle Activity

By Raymond Cloyd, Horticultural Entomology/Integrated Pest Management

Japanese beetle adults feeding on leaf

Japanese beetle, Popilla japonica, adults are present throughout Kansas feeding on many plants in landscapes and gardens, including: roses (Rosa spp), littleleaf linden (Tilia cordata), oak (Quercus spp.), Virginia creeper (Parthenocissus quinquefolia), crabapple (Malus spp.), grape (Vitis vinifera), and common garden canna (Canna x generalis).

The strategies to manage Japanese beetle adult populations are limited and have been for many years. The primary strategy involves spraying contact insecticides to kill the adults in order to reduce plant damage.

Japanese beetle adults are 3/8 to 1/2 of an inch long, metallic green with coppery-brown wing covers. There are approximately 14 white tufts of hair along the edge of the abdomen. Japanese beetle adults live up to 45 days feeding on plants over a four-to-six-week period. Adults feed on many horticultural plants including: trees, shrubs, vines, herbaceous annual and perennials, vegetables, fruits and grapes.

For more information including how to manage Japanese beetle adult populations, read the latest Kansas Insect Newsletter: https://entomology.k-state.edu/doc/extension-newsletters/2023/KSInsectNewsletter%2010.pdf

 

Seeding after Herbicide Application

By Daniele McFadden (recent M.S. graduate at K-State)

With spring in full swing many of you are taking advantage of the warm soil temperatures and overseeding turf areas. Often times we can mistakenly coincide our spring-time herbicide applications with seeding cool-season turf. So, are your new seedlings going to mature and develop if this happens? Research was done over the last two years to evaluate how several herbicides affect the emergence and growth of tall fescue and Kentucky bluegrass when seeded after application.  Following are some takeaways from these experiments.

The good:

  • When dandelions and other common broadleaves start to appear, a standard three-way postemergence broadleaf product containing 2,4-D + MCPP + dicamba (numerous trade names) is often applied. In both the field and greenhouse, we found that seeding tall fescue into an area treated with this herbicide combination was safe on the seedlings, and was comparable to tall fescue growth in areas where the herbicide wasn’t applied.
  • Other combination products used for control of broadleaf weeds were found safe on tall fescue seedlings when seeding was done 0 to 14 days after herbicide application. These herbicides included:
    • Carfentrazone-ethyl + MCPP + 2,4-D + dicamba (SpeedZone)
    • Fluroxypyr + halauxifen-methyl + 2,4-D (GameOn)
    • Triclopyr + pyraflufen-ethyl + 2,4-D + dicamba (4-Speed XT)

The bad:

  • Playing catch-up with yellow nutsedge control? Applying halosulfuron-methyl (Sedgehammer and other trade names) in late summer or early fall for the control of nutsedge could affect your tall fescue and Kentucky bluegrass seedlings if seeding occurs within two weeks of application. Both cool-season grasses emerged in the field with mild chlorotic symptoms that went away within 8 weeks after seeding. However, a closer look at root development showed that seeding tall fescue into soil treated with halosulfuron-methyl significantly stunted development. The Sedgehammer label guidelines clearly state that a four-week delay after application is needed.  Plan your nutsedge control earlier in the summer so it does not interfere with early fall seeding.

The ugly:

  • Did you accidentally apply a preemergence herbicide for crabgrass control before seeding? You might be wasting your seed. Our studies found that seeding tall fescue or Kentucky bluegrass into an area treated with dithiopyr (Dimension) greatly inhibited growth of the seedlings.

Bottom line – reading the label to learn how soon seeding can be done after herbicide application is critical. Labels on some of these products indicate that seeding should be done after a longer interval has passed after application compared to what was observed as required in this research.  Seeding guidelines on labels must be followed; that said, research results from this project provide useful information to herbicide manufacturers and turf managers who may unknowingly seed into herbicide-treated areas.

Evaluating emergence of tall fescue and Kentucky bluegrass when seeded 0 to 14 days after herbicide application in Manhattan, KS.

These research results will soon appear in greater detail in K-State’s 2021 Turfgrass Research Research Report.

***Mention of trade names or commercial products in this article is solely for identification purposes and does not imply recommendation or endorsement, nor is criticism implied of similar products not mentioned by Kansas State University.***

 

Developing a Weed Control Program

(By Jared Hoyle, KSU Turfgrass Research and Extension)

There are many important factors to consider when you are developing a weed control program.  Here is a list of information you should have to help you develop your program.

  1. Turfgrass species
  2. Area needing to be treated.
  3. Correct identification of the problematic weeds.
  4. The time of year the weeds are present.
  5. Determine why the weeds are invading and correct the conditions or cultural practice that are leading to the weed invasion.
  6. Select a chemical that is effective and label for control of the weeds you are treating.
  7. Follow all label instructions!!!!!!!
  8. Apply at the correct time and rate.
  9. Apply herbicides evenly.
  10. Follow up with repeat applications if recommended on the label.

This is also great information to have if you can’t figure out why a weed control method didn’t work.  For more information on diagnosing why a weed control method didn’t work, click here – https://blogs.k-state.edu/turf/i-sprayed-but-i-didnt-kill-the-weed/

Information in this article is from Turfgrass Weed Control for Professionals.

Patton, A.J., M. Elmore, J. Hoyle, J. Kao-Kniffin, B. Branham, T. Voigt, N. Christians, A. Thoms, G. Munshaw, A. Hathaway, T. Nikolai, B. Horgan, L. Miller, X. Xiong, W. Kreuser, R. Gaussoin, D. Gardner, Z. Raudenbush, D. Li, P. Landschoot, D. Soldat, and P. Koch. 2019 Turfgrass Weed Control for Professionals. Purdue University Extension Publication. TURF-100. pp. 128.

Get your copy here – https://www.bookstore.ksre.ksu.edu/Item.aspx?catId=545&pubId=20239

***Mention of trade names or commercial products in this article is solely for identification purposes and does not imply recommendation or endorsement, nor is criticism implied of similar products not mentioned by Kansas State University.***

Don’t forget to follow me on twitter @KSUTurf.

Also, visit our facebook page www.facebook.com/KSUTurf

Roundup for Lawns – UPDATE – K-State Radio Network

(By Jared Hoyle, KSU Turfgrass Research and Extension)

This past weekend I was at a lawn and garden store and saw the Roundup for Lawns display.  Customers were walking by and picking up a bottle.  Some would get Roundup MAXX, Roundup for Lawns and some bought just straight Roundup. I thought to myself, “I hope they know the different between those products.”

Here is some information on the products and a link to Agriculture Today, daily radio program, with Eric Atkinson and Dr. Jared Hoyle.  He explains the difference between the products and even what the bottles look like and why it is important to make sure you pick up the correct product.

Article – https://blogs.k-state.edu/turf/every-homeowner-needs-to-know-the-difference-between-roundup-roundup-for-lawns/

Radio Program – https://www.ksre.k-state.edu/news/radio-network/agtoday-mp3/042017-hoyle.mp3 

Always remember to READ THE LABEL for the correct rate, turfgrass tolerance, and specific instructions before application!!!

***Mention of trade names or commercial products in this article is solely for identification purposes and does not imply recommendation or endorsement, nor is criticism implied of similar products not mentioned by Kansas State University.***

Don’t forget to follow me on twitter @KSUTurf.

Also, visit our facebook page www.facebook.com/KSUTurf

Every homeowner needs to know the difference between Roundup & Roundup for Lawns.

(By Jared Hoyle, KSU Turfgrass Research and Extension)

The other day after eating dinner I was watching TV trying to finally relax.  A commercial came on about Roundup for lawns….  I thought to myself “Oh man, This is going to cause a lot of confusion!”

There is a huge difference in the active ingredients in Roundup compared to Roundup for Lawns.  That is why it is so important to know what you are applying.

Dr. Kevin Frank at Michigan State University just posted a great article about the difference between Roundup and Roundup for Lawns.  Check it out here.

http://msue.anr.msu.edu/news/difference_between_roundup_and_roundup_for_lawns 

Every homeowner needs to know the difference!

I will make a prediction.  Due to the confusion with the names of these products.  I will get at least one phone call this year where someone has killed their entire lawn with glyphosate because they thought they could use Roundup on their lawn and they put out the wrong product.

Always remember to READ THE LABEL for the correct rate, turfgrass tolerance, and specific instructions before application!!!

***Mention of trade names or commercial products in this article is solely for identification purposes and does not imply recommendation or endorsement, nor is criticism implied of similar products not mentioned by Kansas State University.***

Don’t forget to follow me on twitter @KSUTurf.

Also, visit our facebook page www.facebook.com/KSUTurf

Methods of Predicting Crabgrass Emergence

(By Jared Hoyle, KSU Turfgrass Research and Extension)

This morning when I cranked my truck up and headed to the office it was 25 deg F.  Just a couple days ago it snowed.  Just before that it was 80 deg F.  What is going on with the weather? (Every time I make that statement, someone says “Welcome to Kansas!”) With the fluctuating weather and temperatures I get the question “What date do I need to put my preemerge herbicide out on?”

Well this is a trick question because there is no correct answer for it.  Here are some of my thoughts on preemerge timing.

As soon as that first warm front comes through everyone gets excited and ready to work in their lawn.  I have even heard the comment that spring and summer are going to come early this year.  Are they right?  I don’t know but it is something to think about.

But as soon as we get excited about the warm weather we have another cold snap.  So we got all excited and talked about weeds germinating early and needing to get out our preemergence herbicides because the forsythias are blooming. But what happens when it gets cold?  Any crabgrass that “might” have germinated is now dead because of the cold temperatures. So this brings up a lot of discussion between myself and some colleges. Here are just some of the questions we are asked and a couple of comments.

Why do we recommend around April 15th for most of Kansas to put out a preemerge in our lawns?

– April 15th is about the time that we have our “last” frost/freeze. (This also shifts to April 30th in Western/North Western KS and to April 1 in Eastern/South Eastern KS.) This goes along with our concept that I was talking about before.  Even though it may be getting warm we are still might have a cold snap that would end up killing the crabgrass if it emerged. This is the same concept of why we don’t plant crops until after this date as well.  (Something I don’t know anything about but that is what I figure…..)

Should we use soil temperature at 1″ to predict when to put out preemergent herbicide applications?

-Soil temperatures are a great way of determining when to apply your preemerge herbicide.  Scientists say when soils reach a daily average of 55 deg F for about 5 days at a 1″ soil depth then it is time to put out your preemerge.  Well say you go out and measure your soil temperature at 1″  you are not going to get a daily average, you are getting a single point in time.  Does that really represent what is going on?  What if you are maintaining many different properties.  It is not practical to obtain that information.  Good news is that KSU has a website (http://mesonet.k-state.edu) that you can click your closest weather station and get daily maximum and minimum soil temperatures where you can then calculate a daily average.  Bad news it only give you a 2″ or a 4″ soil temperature.  But using the 2″ soil temperatures are going to give you a better idea of the daily averages then going and taking one measurement.

The forsythias are blooming but my redbuds aren’t. Do I still put my preemergent herbicide out?

– This is called phenology – the study of cyclic and seasonal natural phenomena, especially in relationship to climate, plant and animal life.  Many people believe that when the forsythias are blooming then crabgrass is germinating.  That is not 100% true.  When forsythias are in full bloom then we need to be getting “ready” to get our preemerge applied.  Even though we see that this is a good indicator, Dr. Fry and others reported in a study that ornamental plant flowering is not always a good way to predict crabgrass germination and emergence. (Fry, J., S. Rodie, R. Gaussoin, S. Wiest, W. Upham, and A.Zuk. 2001. Using flowering ornamentals to guide application of preemergence herbicides in the Midwestern U.S. International Turfgrass Soc. Res. J. 9:1009-1012.) There are some things to consider when utilizing phenology for crabgrass germination and emergence.  Not all forsythias will bloom at the same time.  It determines where that plant is located in the landscape.  There are micro climates in the landscape.  Think about plants located in roadway medians.  They are typically warmer due to cars and the concrete and asphalt in close proximity.  The same thing goes with crabgrass germination.  Crabgrass will germinated sooner in areas that are warmer, for example (next to sidewalks, bare ground, etc.).

Crabgrass emerging in bare ground earlier than turf

I have heard about growing degree days to predict crabgrass germination. What is that?

– Growing degree days (GDD) use air temperatures instead of soil temperatures within a formula to get a cumulative number of growing degree days.  Using base 50 deg F, once you get to about 200 GDD then crabgrass will start to germinate.  Don’t want to calculate GDDs, don’t worry there is a website that will do it for you. http://www.gddtracker.net  Just enter your area code and click on crabgrass germination on the right side and it will give you the total GDD. It will also show you a prediction for the next couple of days too. GDD do not go backwards, they only accumulate.

So to put this all in perspective using the prediction methods mentioned above this is what we got;

Today is March 14th so using the calendar model for Manhattan we would not put our preemerge out until closer to April 15th for Manhattan.

Using the 2″ soil temperature method because that is what is available to us our daily average soil temperatures (Deg F) have been;

9-Mar 47.6
10-Mar 45.4
11-Mar 43.65
12-Mar 41.15
13-Mar 39.65

With this method we would assume the 1″ soil temperature is higher but we are not to the 55 deg F mark yet. So we are getting close to putting out our preemerge herbicide.

In my back yard my forsythias are blooming.  So that means if I am using the phenology method I need to be getting ready to apply my preemergence.

Lastly, using the GDD model we are at 85 GDD. So I still have some time but getting close.  Remember though that you can get more than one GGD in one calendar day and if I look at the future (prediction on the GDD Tracker website) on March 20th Manhattan will be at 111 GDD. So just in 6 days we would have gained 26 GDD.

Now these rules, concepts, ideas are not bullet proof but it is something to think about when planning your lawn care program.  There is not magic date for anything that you do to you lawn.  You need to make sure you keep up with the temperatures, soil temperatures, precipitation, etc.  The more you know what is going on with your turfgrass the better you will be able to predict crabgrass preemergent applications.  Use more than one method.  This is going to give you the best idea of what to do!

Now by this weekend we are going to get a little warmer but again looking at the 10 day forecast it might get cold again…. Just something to think about.  I hope this got you thinking as a turfgrass manager and how this is going to help you choose products if you are going to have to get applications out earlier or even later after crabgrass has emerged.

Always remember to READ THE LABEL for the correct rate, turfgrass tolerance, and specific instructions before application!!!

***Mention of trade names or commercial products in this article is solely for identification purposes and does not imply recommendation or endorsement, nor is criticism implied of similar products not mentioned by Kansas State University.***

Don’t forget to follow me on twitter @KSUTurf.

Also, visit our facebook page www.facebook.com/KSUTurf

 

When to apply spring preemergence and nitrogen to sports fields

(by Jared Hoyle; KSU Turfgrass Research and Extension)

This is an article a friend of mine at UNL wrote a little bit ago but contains some really great information for you Sports Turfgrass Managers.  Sorry for the delay in getting it out but I think it contains some good information for Kansas on planning your preemergence and nitrogen applications to sports fiends in this crazy spring we have been having.  Enjoy!

When to apply spring PREs and nitrogen

I had to throw this picture of Kauffman Stadium from the 2016 Sports Turf Managers Field Day!
I had to throw this picture of Kauffman Stadium from the 2016 Sports Turf Managers Field Day! Looks Great!

Whats new at #ksuturf farms in Manhattan and Olathe?

(By Jared Hoyle; KSU Turfgrass Research and Extension)

This summer has been a crazy one.  We have been getting ready for field day in Olathe on August 6th (Hope to see everyone out there! – Register here – http://www.eventbrite.com/e/kansas-turf-ornamentals-field-day-tickets-16109376579) but there are a lot of new projects that graduate students, faculty and staff are up to.  Here is just a list of what is going on and we will be talking more about it at field day and at Annual Turfgrass Conference in December!

We have a new GPS navigated robot mower being tested out at Rocky Ford in Manhattan.

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Pre- and Post-emergent herbicide trials at Olathe and and Manhattan. (Photo form Olathe).

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Influence of tall fescue mowing height on crabgrass populations demonstration at Olathe.

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I have been traveling everywhere. (Had to throw that in there)

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New zoysaigrass variety trials at Rocky Ford in Manhattan.

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Ross Braun (KSU Turfgrass PhD Graduate Student) has been evaluating multiple turfgrass species, mowing height and traffic in drought conditions.

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Evan Alderman (KSU Turfgrass MS Graduate Student) installed a new fairway (5/8″) of ‘Cody’ buffalograss at Rocky Ford.

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There is a new ornamental herbicide testing facility installed at the forest research center in Manhattan to evaluate potential turfgrass herbicides to ornamental plants.

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The use of adjuvants with Pylex  and triclopyr combination demonstration trial at Olathe. Brown patch control research trial was installed at Olathe this summer. New granular products for broadleaf weed control (Olathe – Photos not shown).

Dr. Bremer and Ross Braun (KSU Turfgrass PhD Graduate Student) has been studying greenhouse gas emissions under drought conditions at Rocky Ford.

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More traveling…

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Lastly, I would like to congratulate Dr. Zane Raudembush for completing his PhD this past spring.  Good luck in all your do Zane.

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This is not all of what have been going on but just wanted to share some of the pictures of some of the new things that are going on here in the KSU Turfgrass Program.

Don’t forget to come out to field day August 6th and see some of the research that we have been conducting.  Thanks and have a great rest of the week!

Jared