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K-State Turfgrass

Month: June 2018

Yellow Nutsedge Control

(By Jared Hoyle, KSU Turfgrass Research and Extension)

As I talk to turfgrass professionals across the state I hear that some are getting plenty of rain while others are getting none. This time of the year we think that if we are getting some precipitation we will have yellow nutsedge popping up everywhere. Well that is not always true. Yellow nutsedge does favor moist soils but it can also grow in well-drained sites.

One of the easiest ways to identify yellow nutsedge is by a couple special features;

  • erect
  • persistant
  • yellow inflorescence
  • gradually tapering leaves to a sharp point
  • tubers not in chains
  • triangular stem

To control yellow nutsedge, if you can get applications out before tuber production then you will see increased control.  But beware, yellow nutsedge will continue to grow as long as the environment is favorable for growth, so more than one application maybe necessary.

If using a herbicide application timing is critical.  During mid summer yellow nutsedge starts making tubers and if you apply herbicides before tuber production you will get better control.  If you wait until the yellow nutsedge is big and starting to make tubers then you will be playing catch-up all year. So sooner is better.  Don’t wait for it to get too big.

Here are some options for yellow nutsedge control for turfgrass professionals;

  • sulfentrazone
  • halosulfuron
  • iodosulfuron
  • mesotrione
  • bentazon
  • triflozysulfuron
  • flazasulfuron
  • sulfosulfuron

There are many different products out there that contain these active ingredients so just make sure you have an active ingredient that has yellow nutsedge control! Also make sure you check for turfgrass tolerances.

****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

Return of the Goathead – Puncturevine

(By Jared Hoyle, KSU Turfgrass Research and Extension)

Return of the Goathead – Sounds like a horror movie! Well, right now I do feel like it is “Return of the Goathead”. Just about everywhere I look I see a goathead. Goathead is also known as puncturevine (Tribulus terrestris). It is a summer annual broadleaf weed that can cause headaches for many people.

 

This weed is a prostrate mat-forming weed that can produce many burs with sharp spines. This weed if invading a lawn, athletic field, playground and parks can cause injury to children and animals if they fall on or step on the sharp spines. It can also be found in disturbed areas as fields, pastures and roadsides. Good news is that many of the broadleaf herbicides are effective.

 

****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

“K-State to close horticultural research center near Wichita”

We learned this news last week about the J.C. Pair Center, where we conduct multiple research trials and hold extension field days:

“MANHATTAN, Kan. — Reductions in base support from the state and recent enrollment declines have led to the decision to close Kansas State University’s 120-acre John C. Pair Horticultural Center in Haysville.”

Research farm opened in 1970, focusing on woody ornamentals, turfgrass

Here is the link to the full press release:

http://www.ksre.k-state.edu/news/stories/2018/06/pair-center-closure.html

Listed on the right-hand side of that page is the contact information to share comments or raise questions:

Ernie Minton
785 532-6148
eminton@ksu.edu

 

 

 

Why is it August in June? 16 options for reducing stress in putting greens

 

(Megan Kennelly, KSU Plant Pathology)

The average daily high for June 15 in Manhattan is 86.1, and the average nightly low is 63. We have been well above those averages. Ugh! June is supposed to be our time of “things are still okay out there… July and August are around the corner, but for now we are fine.” However, this year, August is here now! Along with the heat, it is very dry out there, as shown on the most recent US Drought Monitor map:

What can you do to reduce summer stress in putting greens?

The Chemical Control of Turfgrass Diseases publication (free online!) includes an excellent list of 16 practices that can reduce summertime stress. Are you doing some of those practices already? Yes, you probably are. Are there some you are not trying? Maybe – you might test some out, or talk to your peers about what they are doing. Are some just not feasible for your site? Probably – and that’s okay. Check out the whole menu of 16 options and see if it generates any new ideas. You can find the whole list starting on page 6 of Chemical Control of Turfgrass Diseases which, in short, includes information about mowing height, watering, fertility, foot traffic, dew, phytoxicity warnings, and more.

 

With that in mind, here are some pictures to illustrate the importance of roots during stressful summer conditions:

 

KSU Turf Field Day – August 2!

(Jared Hoyle, KSU Horticulture & Natural Resources)

The Kansas Turfgrass Field Day will be held Thursday, August 2 at the Rocky Ford Turf Research Center in Manhattan.

The field day program is designed for all segments of the turf industry – lawn care, athletic fields, golf courses, and grounds maintenance. Included on the program are research presentations, problem diagnosis, commercial exhibitors, and equipment displays. There will be time to see current research, talk to the experts and get answers to your questions.

Pesticide recertification credits in 3A and 3B are available, as well as GCSAA education points.

You can register online at https://2018turfday.eventbrite.com

Are you smarter than a slime mold?

 

(Megan Kennelly, KSU Plant Pathology)

Look what showed up in my mulch yesterday morning?

 

Hey, what’s that stuff? Slime molds! They can look pretty alarming, and they can pop up seemingly overnight. They are pretty harmless, and you can read more HERE and if you would like a fascinating glimpse into how these organisms work there is a short video clip HERE called “Are you smarter than a slime mold?”

Here is another version of slime mold – these photos were submitted to me this morning over email. Look closely and you’ll see little gray blobs up on stalks:

And, to round things out, here are a few from last year:

 

(Courtesy Ron Reese)

Courtesy Jacob Weber:

 

Courtesy Ron Reese:

Got turf problems? Look underground, part 2

(Megan Kennelly, KSU Plant Pathology)

“What disease is this?” Brown patch, Pythium, Leaf spot?

Answer – none of the above!

 

A couple weeks ago I posted about thatch and organic matter:

Declining turf? Look below the surface

Last week I received another set of samples where turf was in decline, a disease was suspected, but the underlying issue was thatch or organic matter buildup.

Layering in the putting green:

 

Very thick thatch in the fairway:

Don’t forget to check underground.

Hot and sticky summer weather = brown patch and Pythium

(Megan Kennelly, KSU Plant Pathology)

 

Is this brown patch in a tall fescue home lawn? Look for lesions to be sure! See below!

It’s that time of year when you go outside in the morning and immediately start to sweat. Ugh.

High humidity means that the temperatures stays high even overnight. Sticky, humid nights = conditions ripe for brown patch and foliar Pythium.

Brown patch is common in tall fescue lawns, perennial ryegrass athletic fields and fairways, and bentgrass putting greens. I’ve been hearing reports of brown patch popping up in the past few days.

Foliar Pythium is common in bentgrass and rye fairways, and we occasionally see it in lawns that are very lush and wet. Foliar Pythium is very rare on greens. I haven’t seen any yet, but with humidity and nighttime lows in the 70s it’s a possibility.

Fungicides and cultural practices for both diseases are spelled out in detail in the publication Chemical Control of Turfgrass Diseases.

 

In tall fescue, brown patch symptoms can resemble drought or other injury. If in doubt, check around for the characteristic lesions:

Both diseases can produce mycelium in the turf during wet, humid, dewy mornings. With Pythium, usually the turf looks matted down and greasy.

Brown patch:

Pythium – grass is matted down and greasy/mushy:

Not sure? You can always send a sample to the KSU Plant Diagnostic Lab.