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K-State Turfgrass

Category: Cultural Practices

Turf health problems, above and below ground. And why your putting green soil should not look like tiramisu.

(Megan Kennelly, KSU Plant Pathology)

The soggy weather continues, and diseases are in full swing. Dewy, wet mornings lead to mycelial growth of the pathogens that cause dollar spot or foliar Pythium. These are mainly golf course concerns, but the diseases can occur at other sites.

Here is a sample that came into the lab, loaded with foliar Pythium:

IMG_3151

It is from a golf course fairway at a site that has received a lot of rain and some foggy mornings where everything is wet-wet-wet.

For management info on foliar Pythium, you can check these links:

http://www2.ca.uky.edu/agcomm/pubs/ppa/ppa1/ppa1.pdf

(scroll through to the Pythium part on p.17)

http://extension.missouri.edu/p/IPM1029-17#Pythiumfoliarblight

 

Root health continues to be a problem, especially on putting greens. We’ve posted a lot of information this year about wet soils leading to physiological decline and triggering Pythium root rot in some cases (see links at bottom of this post). Putting greens with poor drainage, less-than-ideal construction, or a build-up of organic matter are particularly susceptible. Here are some putting green rootzones with a lot of organic matter build-up, visible as dark layers:

layers FullSizeRender

All those layers kind of look like tiramisu…mmm… yummy… getting distracted.

tiramisu

Unlike delicate layers of a tiramisu, layering in a putting green rootzone is NOT a delectable delight. Another complication of poor drainage is that it can make the turf more prone to anthracnose. I received a couple of samples in recent days with crown rot anthracnose. Both also had layering problems and root decline.

There is some information about anthracnose here:

http://www.bookstore.ksre.ksu.edu/pubs/EP147.pdf

and here is an excellent list of best management practices:

http://turf.rutgers.edu/research/bmpsanthracnose2015.pdf

Many of the practices to reduce anthracnose also promote overall turf health. That is, when you implement agronomic practices to promote good rooting you also reduce the risk of anthracnose and other problems. You may not be able to do ALL of the beneficial agronomic practices you would like, due to budgetary limits or lack of equipment or golfers’/greens committee opinions, but the more you can fit in, the better.

We posted on these topics earlier this year. If you want to go back and review, here are some links:

https://blogs.k-state.edu/turf/season-long-agronomic-practices-to-reduce-anthracnose-risk-in-putting-greens/

https://blogs.k-state.edu/turf/root-decline-it-aint-benign/

https://blogs.k-state.edu/turf/best-management-practices-for-turfgrass-anthracnose/

https://blogs.k-state.edu/turf/your-turf-is-trying-to-bike-up-a-mountain/

https://blogs.k-state.edu/turf/bentgrass-declining-its-from-western-europe-you-live-in-kansas-by-dr-fry/

 

 

It’s Finally September – That Means Football and Fescue

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

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September is almost here and that means it is prime time for football and to fertilize your tall fescue or Kentucky bluegrass lawns. If you could only fertilize your cool-season grasses once per year, this would be the best time to do it.

These grasses are entering their fall growth cycle as days shorten and temperatures moderate (especially at night). Cool-season grasses naturally thicken up in the fall by tillering (forming new shoots at the base of existing plants) and, for bluegrass, spreading by underground stems called rhizomes. Consequently, September is the most important time to fertilize these grasses.

Apply 1 to 1.5 pounds of actual nitrogen per 1,000 square feet. The settings recommended on lawn fertilizer bags usually result in about 1 pound of nitrogen per 1,000 square feet. We recommend a quick-release source of nitrogen at this time. Most fertilizers sold in garden centers and department stores contain either quick-release nitrogen or a mixture of quick- and slow-release.

The second most important fertilization of cool-season grasses also occurs during the fall. A November fertilizer application will help the grass green up earlier next spring and provide the nutrients needed until summer. It also should be quick-release applied at the rate of 1-pound actual nitrogen per 1,000 square feet.

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Low Water Use Turfgrass Event – Hays, KS

Tuesday evening, Sept. 20 is set for the annual Horticulture Night at the Kansas State University Agricultural Research Center in Hays. This year the emphasis is on low water use turfgrass demonstration plots, tomato and pepper varietal trials, and the Prairie Star flower performance trials.  The event is scheduled later in the summer this year than usual so attendees can better view the results of the complete season.

Dr. Jared Hoyle will be there to answer any turfgrass questions you might have!

http://www.ksre.k-state.edu/news/news-stories/2016-news-releases/august/horticulturenight-hays.html

 

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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.

Converting Tall Fescue to Buffalograss – VIDEO

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

Are you thinking about converting your tall fescue lawn into buffalograss?  If you are, new research is currently being conducted at Rocky Ford Turfgrass Research Center in Manhattan, KS to pin down the best herbicide application timing to reduce the amount of time that you don’t have turf in your lawn.

Check out the video here of KSU Turfgrass Research Technician, Jake Reeves, discuss this research and how it will impact turfgrass areas across Kansas.

The 2016 Turfgrass Research Reports Now Online!

(By Jared Hoyle: KSU Turfgrass Research and Extension)

Every year we create new turfgrass research reports.  This year we have lots of new information from the release of a new zoysiagrass to unmanned aircraft systems for drought monitoring.

photo contest

Listed below is a list of topics and links to the 2016 reports.  Enjoy!

  1.  Release of KSUZ 0802 Zoysiagrass
    J. Fry and Ambika Chandra
  2. Nitrous Oxide Emissions and Carbon Sequestration in Turfgrass: Effects of Irrigation and Nitrogen Fertilization (Year 1)
    R. Braun, D. Bremer, and J. Fry
  3. Small Unmanned Aircraft Systems Detect Turfgrass Drought
    D. Bremer and Deon van der Merwe
  4. 2013 National Turfgrass Evaluation Program Bermudagrass Test: 2015 Data
    L. Parsons, J. Griffin, and J. Hoyle
  5. 2012 National Turfgrass Evaluation Program Tall Fescue Test: 2015 Data
    L. Parsons, M. Kennelly, J. Griffin, and J. Hoyle
  6. Influence of Glyphosate Timings on Conversion of Golf Course Rough from Tall Fescue to ‘Sharps Improved II’ Buffalograss
    J. Reeves, J. Hoyle, D. Bremer, and S. Keeley
  7. Late Pre-Emergent Control of Annual Bluegrass with Flazasulfuron & Indaziflam
    J. Reeves and J. Hoyle
  8. Evaluating the Effects of Simulated Golf Cart Traffic on Dormant Buffalograss and Turfgrass Colorants
    E. Alderman, J. Hoyle, J. Fry, and S. Keeley
  9. Preventative Control of Brown Patch with Select Fungicides
    E. Alderman, J. Reeves, and J. Hoyle
  10. Development of Cold Hardy, Large Patch Resistant Zoysiagrass Cultivars for the Transition Zone
    Mingying Xiang, J. Fry, and M. Kennelly
  11. Evaluating Zoysiagrass-Tall Fescue Mixtures in Kansas
    Mingying Xiang, J. Fry, and M. Kennelly

Lawn Problem Solver

(By Jared Hoyle; KSU Turfgrass Research and Extension)

Do you have an unwanted weed or a disease that you can’t figure out what it is or how to control it?  Check out the Lawn Problem Solver at the KSU Turfgrass Website.  Is has information about how to identify those pesky weeds, diseases, insects and more.

Also, for homeowner extension questions please locate your local area or county extension agent here – http://www.ksre.k-state.edu/about/stateandareamaps.html 
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USGA’s Bob Vavrek gives insight on the “Turf Trifecta”

Bob Vavrek explains how the hot humid weather finally has made life miserable for maintaining cool-season turfgrass putting greens.  There are options out there to help out your putting greens but you always want to make sure to minimize injury to the turf during these stressful times.

Check out the article on the USGA website here.

http://www.usga.org/course-care/regional-updates/central-region/the-turf-trifecta.html

 

Your turf is trying to bike up a mountain

(Megan Kennelly, KSU Plant Pathology)

I am not great with sports metaphors, but I’m going to give this a chance. I was looking at declining roots in the microscope and thought…

Growing bentgrass putting greens in Kansas in summer is like coaching an athlete riding the Tour de France.

Actually, it’s even harder because instead of a mere 21 day grind it can be a 3-month grind.

THE PELOTON CLIMBS THE COL DU GALIBIER ON STAGE SEVENTEEN OF THE 2008 TOUR DE FRANCE

In my story here, you are the coach, the turf is the athlete, and the rootzone/soil is the bicycle.

Maybe you are lucky and have a high budget “bike” for your athlete. The bike (the rootzone) was well-built, top-of-the-line, with excellent construction, drainage, excellent sand, etc. The biker (the turf) undoubtedly will still have to work hard, especially in the “mountain stages” (those weeks with high humidity, high temperatures of 100 and lows of 81). But at least the bike itself (the soil) is not going to add to the challenge and make it any harder than it needs to be.

Maybe you are less lucky, though, and what you have for your athlete is this, a Huffy beach cruiser:

huggy-mens

It’s what your sponsors are able to provide for your athlete.  When your turf is not riding the Tour de France, like when it is growing from September through May, this bike works okay. It gets the job done.  However, when the going gets tough (June, July, August), it is VERY tough. It is VERY VERY VERY tough in the mountain stages. The bike is slow and clunky. The turf is already stressed, and the bike just makes it worse.

What can you do?

Like a coach training an athlete for the Tour de France, preparing your grass for summer is a year-round commitment. Build the best bike you can. That is, build the best soil profile you can. Aerify and verticut in the fall. Reduce shade and improve air flow. Get on a regular topdressing program.

Your athlete needs food, too, not just a bike. Green photosynthetic tissue = food. Raise the mowing height a tiny bit, or roll instead of mowing, or skip mowing now and then. Don’t just do this in summer – consider doing this in spring/fall when the grass is growing. Put down adequate N in the fall, and spoon-feed during summer. Your athlete can’t ride up the mountain if it is starving.

Explain to your sponsors (your golfers/members) that if your budget is a Huffy beach cruiser, they can’t expect that same as with a high budget piece of equipment. Maybe they can increase the budget, and at least get a moderately prized bike (pay for some extra aerification in the fall, buy some equipment to do some needle-tining in summer). Maybe they don’t even know it’s a Huffy, and with some explanation, you can get permission to rebuild some problematic greens. Dig up some cores, show it to them, and talk about drainage, root health, oxygen, etc. Communication is critical.

If the athlete is showing signs of stress, get help right away.

I know this metaphor was a little clumsy – if you made it to the finish, congratulations!

“Bentgrass Declining? It’s from Western Europe – You Live in Kansas” by Dr. Fry

Our own Dr. Jack Fry is an expert on cool-season turfgrass physiology. He co-wrote a book on the topic:

book

and he developed an online GCSAA class (click HERE) as well.

So, every year, around this time, I end up asking him about mid-summer turfgrass decline. I asked Jack to write some thoughts for this blog:

 

In the midst of a summer with 100+ F temperatures, it’s worthwhile to consider some of creeping bentgrass’s preferences and management strategies that might be helpful to reduce its stress, and yours.  See, the thing about creeping bentgrass on putting greens is….

  • It came from Western Europe. You live in Kansas.
Average July maximum temperature (°F) Average July minimum temperature (°F)
London, England 72 55
Manhattan, Kansas 90 68

 

  • Its roots die first, then its leaves. Keep the roots happy and you’ll have happy bentgrass and happy golfers.
  • Its roots prefer to grow at 55 to 65 °F; root growth slows even as low as 80 °F. This summer, temperatures near the surface of greens have been over 100 °F.
  • Faults with construction, drainage, management practices may produce a quality turf surface for 10 or 11 months of the year. It’s the one or two other months that cause problems.   If you want to avoid bentgrass decline, then start with a good rootzone.
  • Rootzones that hold water are warmer and also have less oxygen for root growth. If you don’t have an ideal rootzone, work to improve it in the fall and spring with aggressive core aerification and topdressing.
  • The benefits of coring are often seen during summer stress. Why are there green polka dots within the brown turf?  Turf in those spots has roots!green_in_aerification_holes
  • Opening the green’s surface with small, solid tines or spikes can help with water infiltration and root growth during midsummer. Don’t overdo it – the turf is under stress.
  • Although superintendents suspect (and often hope) that a disease is causing the problem in mid-summer, over half of the samples that are evaluated in our lab show no disease.
  • In our climate, air movement across the surface of the green is critical for bentgrass health. If your greens are surrounded, let them free!
  • Maximize summer airflow from the south, but also vent to the north (just like opening two windows to get cross flow in your house).
  • Hand watering can be used to address deficiencies in water distribution of the irrigation system, target localized dry spots, and deal with inconsistencies in water retention and drainage in the root zone. It shouldn’t be overdone or underdone- train and use your best help for handwatering.
  • Syringing refers to applying a light mist of water droplets to leaves only, and then relying upon evaporation of that water to help cool the leaf surface. How effective do you think that is on a humid, July day?  Not very, unless you use a fan to encourage evaporation from the leaf!
  • Trees use light for photosynthesis, so does bentgrass. If trees are shading the green, which is getting the light – the tree, or the turf?
  • Cultivars that are more dense get less Poa invasion, and Poa is more likely to die during summer stress than bentgrass. Plant newer, denser cultivars to reduce Poa.( The photo shows Poa checking out in the heat.)poa dying
  • Light applications of nitrogen can be beneficial during heat stress (0.10 lb. N/1,000 sq. ft.)
  • Newer cultivars have been shown to be more heat tolerant than Penncross, but even these will experience decline during prolonged heat.
  • Clean up laps are often the first to show symptoms of stress. Why?  Excessive traffic and wear.  Have you considered a dedicated mower with a slightly higher mowing height for the clean up lap?  Do you skip clean up laps on some days?mow