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Turfgrass Care for Homeowners on the K-State Radio Network

(By Jared Hoyle, KSU Turfgrass Research and Extension)

Just recently I was invited to speak with Eric Atkinson, host of Agriculture Today a daily program distributed to radio stations throughout the state. It features K-State agricultural specialists and other experts examining agricultural issues facing Kansas and the nation. I spoke with Eric about some issues that Kansas homeowners might be facing with their lawns and a couple things that homeowners shouldn’t worry about this year.

Click on the link below and hear more about;

  • possible winter injury
  • fertility
  • weed control
  • and more!

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

“An ounce of prevention is worth a pound of cure.” by Benjamin Franklin – (That Goes for Preemergence Herbicides Too!)

(By Jared Hoyle, KSU Turfgrass Research and Extension)

“An ounce of prevention is worth a pound of cure” – Benjamin Franklin

When I start talking about pre-emergent herbicides this quote from Benjamin Franklin always pops in my head.  Although, Ben was giving fire-fighting advice to Philadelphians because fires were a dangerous threat at that time it does apply to many things we are dealing with right now, including spreading wild fires. (I won’t comment on that because I have no idea how to manage wild fires.) But I will talk about Pre-remergent herbicides.

Pre-emergent (PRE) herbicides prevent summer annual weed (For Example, crabgrass, goosegrass, annual sedges, and spurge) seeds from developing into mature plants.  The reason we use PRE herbicides for summer annual weed control is because these summer annuals come back every year from seeds.  So if we can stop the seed from growing then we don’t have to deal with the weeds later in the season.

For all that don’t know how a PRE herbicide works here is a very short explanation.  They do not keep the seed from germinating but kill the young germinating plant.  With few exceptions they have no effect on existing plants, so they must be applied before germination.

But like in everything in life there is an exception.  Dithiopyr can kill crabgrass as long as it is young (two- to three-leaf stage, see photo below of three leaf crabgrass) and still have some residual for continued PRE activity. It doesn’t last as long as some of the other PRE herbicides but there is flexibility if you miss your window of opportunity to apply.

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So when do I put out the PRE application for summer annual weed control? Well, it depends on many things.  What summer annuals you have? Where are you located in Kansas?  Many times turfgrass managers center their PRE applications around crabgrass germination.  Crabgrass “typically” begins to germinate around May 1 or a little later in KS. April 15 is a good target date for applying a PRE because it gives active ingredients time to evenly disperse in the soil before crabgrass germination starts. The April 15 target works well for most of the state, but for southeast Kansas April 1 is more appropriate, and for northwest Kansas May 1 is best.  Additionally, weather varies from one spring to the next (As we can see this year where it is getting warmer earlier!), and with it the timing of crabgrass germination. Some turfgrass managers base their PRE application around the bloom of the Redbuds but other ways can be used as well.  Crabgrass germinates when the soil at approximately 1 cm deep reaches 55° F.  So watch your soil temperatures to see when the soil consistently reaches 55° F. Here is a great website that will give you soil temperatures for your area.

http://mesonet.k-state.edu/weather/historical/

PRE herbicides do not last forever once applied to the soil. Microorganisms and natural processes begin to gradually break them down soon after they are applied. If some products are applied too early, they may have lost much of their strength by the time they are needed.  Additionally, PRE herbicides have different half-life, Koc, water solubility, and vapor pressure. This can determine how fast microbial, chemical and physical decay occurs along with infiltration, volatilization, leaching, and run-off.

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Therefore, not all PRE herbicides are created equal.   Here is a list of PRE herbicides, the weeds they target and some concerns that you might want to know before applying.

Active Ingredient Weeds Controlled Concerns or Comments
benefin summer annual grasses, annual bluegrass, some-small seeded broadleaves Do not use on golf course greens.
prodiamine summer annual grasses, annual bluegrass, henbit, chickweed, spurge, some-small seeded broadleaves Only apply to well established turfgrass.
bensulide annual grasses, some broad-leaves Do not use on putting greens composed of  > 50% Poa annua.
florasulam broadleaves, dandelion, prickly lettuce, clover Packaged with Dimension 2EW, florasulam great cool temperature activity, Prevents flowering in some broadleaves (dandelions).
dithiopyr summer annual grasses, annual bluegrass, yellow-woodsorrel, some small-seeded broadleaves PRE and early post-emergence activity on crabgrass.
isoxaben broadleaves such as chickweed, henbit, spurge, plantain, others Tank-mix with a grass herbicide for broader spectrum.
pronamide annual bluegrass, perennial ryegrass, other grassy & broadleaf weeds. Do not use on cool-season turf. Restricted use pesticide.
pendimethalin summer annual grasses, annual bluegrass, yellow-woodsorrel, some small-seeded broadleaves Not recommended for turf severely thinned due to winter stress.  Split applications can be made for extended control.
metolachlor annual bluegrass, crabgrass, sedges Do not use on cool-season turf.
simazine summer annual grasses, annual bluegrass, henbit, chickweed, spurge, some-small seeded broadleaves Do not use on cool-season turf.
ethofumesate annual bluegrass, annual grasses, some annual broadleaves See label for reducing annual bluegrass in cool-season turf.
oxadiazon summer annual grasses includinggoosegrass, annual bluegrass, some-small seeded broadleaves Ronstar G and Oxadiazon 2G are only formulations labeled for use on cool-season turf.
indaziflam annual grassy and broadleaf weeds in turf Do not use on cool-season turf.
oryzalin summer annual grasses, annual bluegrass, some-small seeded broadleaves Do not use on cool-season turf except tall fescue.
dimethenamid bittercress, crabgrass, goosegrass, purslane, sedges, spurge On golf courses: Can be used on cool- and warm-season.  Other turf areas: Warm-season only.
siduron crabgrass, bermudagrass (suppression) Does not control goosegrass or annual bluegrass.

Information in this table was acquired from “Turfgrass Weed Control for Professionals” by A. Patton and D. Weisenberger, Purdue University (and 11 collaborating states including Kansas). For more information about purchasing this publication see;

https://blogs.k-state.edu/turf/new-weed-control-publication-for-turfgrass-professionals/ 

 

***There are many combination PRE herbicides that combine these active ingredients with each other and with other POST-emergent herbicides***

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

Knotweed – Last year it was April, Now its February!

(By Jared Hoyle, KSU Turfgrass Research and Extension)

Last year I did one of my first Turfgrass Selfie Series on knotweed control in April.  The knotweed had germinated and started to mature.  Just a couple weeks ago I was walking into my office and I saw knotweed already germinating.  (See picture below – Photo taken Feb. 22, 2017)

So needless to say.  If you didn’t get your preemerge out and you have a history of knotweed it is time to go out and attack the knotweed and other broadleaf weeds you have lingering around.  These weeds are easier to control now when they are young compared to when they get mature.

Below is the Knotweed Control Turfgrass Selfie Series Video I did last year but here are the take home messages;

  • Early germinating summer annual
  • Likes compacted soils/flooded areas
  • 2,4-D = fair control
  • 2,4-D + triclopyr or dicamba = excellent control
  • metsulfuron can be used in warm-season turf
  • PRE applications must be done in the Fall

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

New Weed Control Publication For Turfgrass Professionals

(By Jared Hoyle, KSU Turfgrass Research and Extension)

In 2016 Dr. Aaron Patton and Daniel Weisenberger reached out to surrounding universities to collaborate on producing a multi-state Turfgrass Weed Control for Professionals Publication.  There are 11 states, including Kansas, that worked together to help produce the 2017 edition.

 

Guide provides weed identification and control information that turfgrass professionals can use to develop effective weed control programs for golf courses, athletic fields, sod farms, lawns, and other turfgrass systems. Recommendations apply to most states, with input from experts in IL, IN, IA, Kansas, KY, MI, MN, MO, NE, NY, OH, and WI.

It contains images and information for identifying 105 different weed species.

 

 

Covers herbicide selection in:

  • Nonselective herbicide/fumigants for renovation
  • Nonselective herbicides for border maintenance
  • Preemergence herbicides
  • Postemergence broadleaf herbicides
  • Postemergence grass herbicides
  • Postemergence sedge herbicides
  • PGRs for general turf
  • PGRs for putting greens
  • Herbicides labeled for putting greens (PRE and POST)

The publicationl also covers many other weed control aspects like;

  • Which herbicide works best for each weed.
  • Includes notes and comments on each herbicide.
  • Control of tough weeds.
  • Provides handy comparisons of broadleaf herbicide ingredients.
  • Covers fundamentals of how herbicides work
  • frequently asked questions.

GET YOURS TODAY! 

For an electronic download copy for 12.00 click here – https://mdc.itap.purdue.edu/item.asp?item_number=Turf-100-W#.WMFVKGVuD8s

For a hard copy delivered to your door (20.00) click here – https://mdc.itap.purdue.edu/item.asp?item_number=TURF-100#.WMFVDWVuD8u

Can you tell the difference? – Little Barley Control for Homeowners

(By Jared Hoyle and Ward Upham; KSU Research and Extension)

 

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Can you tell the difference?  There are two difference weeds in the picture above but they look a lot alike!  Not only do they look a lot alike but they both have similar attributes.  Below will tell you which one is which.

 

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Many people mistake little barley (Hordeum pusillum) for a little foxtail because the foxtail and little barley seedheads are similar. However, little barley is a winter annual that comes up in late September – October and spends the winter as a small plant. It thrives in the cooler spring temperatures, forms seed heads and dies out usually by July. Foxtail, on the other hand, is a summer annual that does well in hot weather. Also, foxtail will not produce seedheads until mid- to late-summer.

 

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So, why are we talking about little barley now? Because now is the time to control it for next year. The best control for little barley is a thick lawn that is mowed high enough that sunlight does not hit the soil. Little barley seed will not germinate in such conditions.  Overseeding now can thicken up a tall fescue lawn and prevent a little barley infestation.

However, if you do not plan to overseed, preemergence herbicides can be used to provide at least partial control of this weed. The only preemergence herbicide that I know is labeled specifically for little barley is Surflan. It is also sold under the name of Weed Impede by Monterey Lawn and Garden. Surflan can only be used on warm-season grasses (bermudagrass, buffalograss, zoysiagrass) and tall fescue grown in warm-season areas such as Kansas. However, Dimension (dithiopyr), is labeled for barley (Herodium spp.) which would include little barley and therefore
can be used to keep this weed under control. Because little barley is a winter annual, apply the preemergence herbicide now and water in to activate. If overseeding, do not apply any preemergence herbicide as it will interfere with the germination of tall fescue.

****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

Broadleaf Weed Control and PRE Crabgrass Control – VIDEO

(By Jared Hoyle and Jake Reeves, KSU Turfgrass Research and Extension)

Just a couple weeks ago the turfgrass team held the Annual Kansas Turfgrass Field day in Manhattan, KS at the Rocky Ford Turfgrass Research Center.  At one of the stops Dr. Jared Hoyle talked about new products that are on the marked for post-emergent broadleaf weed control and pre-emergent crabgrass control.  If you couldn’t make it out to field day here is a short little video about what you missed.

New Turfgrass Selfie Series on YouTube – Knotweed Control

(By Jared Hoyle; KSU Turfgrass Research and Extension)

selfieWe have just started something new on Youtube and it is call the Turfgrass Selfie Series.  We will be uploading short informational and educational videos about turfgrass management to our new Youtube page.  These videos are not professional done as we are turfgrass researchers and not very good videographers. (I fell like I did pretty good making this video with my iPhone. Hopefully we will get better at making videos in the future!)

The first video in the series is on Knotweed control. Check it out!

Paint and Glyphosate Research Update Published in GCM

(By Jared Hoyle and Jake Reeves; KSU Turfgrass Research and Extension)

In July’s issue of Golf Course Management Magazine on page 95,  Jake Reeves’s (KSU Turfgrass Research Technician /Graduate Assistant) and Jared Hoyle’s research was featured in the Cutting Edge section by Teresa Carson.

Take a look on page 95 and read more about “Timing effects of turf paint + glyphosate applicant on grassy weed control”

http://gcmdigital.gcsaa.org/i/532236-jul-2015

2014-2015 Research Plots at Stagg Hill Golf Course in Manhattan, KS.
2014-2015 Research Plots at Stagg Hill Golf Course in Manhattan, KS.

We repeated the research in 2014-2013 and will have the final results out soon.  The results so far demonstrate that adding turfgrass paints to dormant zoyisagrass glyphosate applications can increase gassy weed control.

 

Weed Control For Turfgrass Professionals 2015 Edition

(By Jared Hoyle, KSU Turfgrass Research and Extension)

AY-336-2015There is a great resource to all the turfgrass professionals out there.  It is called “Turfgrass Weed Control for Professionals – 2015 Edition”.  It was developed from Purdue University from some great turfgrass scientists.

It is only 12 dollars for a print copy and you can download it in a PDF file for only 10.  I highly suggest getting one for reference.

 https://mdc.itap.purdue.edu/item.asp?item_number=ay-336#.VQsaut4aj8s

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