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Tag: brown patch

Nitrogen Rate and Fungicide Had Big Impact on Brown Patch in Tall Fescue this Summer

If you were at field day on August 3rd, you likely saw the experimental area that was highlighted by Dr. Megan Kennelly.  A turf-type tall fescue blend has been treated the past two years as either: High N level; or Low N level.  High level involved 4.5 lbs of N/1,000 ft2/yr  (Months applied listed in lbs N/1,000 ft2 – 1 in April; 1 in May; 1.5 in Sept.; 1 in Nov) and low N level was 1.5 lbs of N/1,000 ft2/yr (single application in September).  In addition, half of the plots receiving these treatments either received two fungicide applications from azoxystrobin (Heritage) each growing season or none.  You’ll see a photo below of how N impacted brown patch on tall fescue.  More details will come out in the 2024 K-State Turf Research Report.  Bottom line summaries:

  • High N levels provided high quality turf, but fungicide application was required to maintain it when brown patch infection began.  Turf receiving high N without fungicide declined quickly in quality starting in July.
  • Brown patch levels were comparable in July in turf receiving high N from standard urea, humic coated urea, or combinations of 50% slow release + 50% quick release N.
  • Low level N generally provided turf quality that was at or just below an acceptable level (but not high quality) and had little brown patch even when fungicides were not applied.

    Impact of N level on brown patch in tall fescue with no fungicide application.

Brown Patch on Tall Fescue

By Ward Upham and Jack Fry

We have been receiving numerous reports of brown patch showing up on tall fescue. This disease is favored by warm night temperatures and extended periods of leaf wetness. If you go outside in the morning and the lawn is covered with dew and the temperature is in the high 60’s or higher, it means that conditions are getting right for brown patch. The fungus is primarily a leaf pathogen and does not attack the roots. During severe outbreaks, the fungus may invade the lower leaf sheaths and crown and kill plants. But in most cases, the turfgrass can recover from brown patch. This recovery may take two to three weeks, depending on weather.

There is no way to eliminate brown patch from a lawn. It will persist indefinitely in the soil. Therefore, the disease is not carried from one lawn to another. In almost all cases, the limiting factor for brown patch development is the weather, not the amount of fungal inoculum. Although you can’t eliminate the fungus, cultural practices – especially irrigation – can help control it. Don’t water in the evening; instead, water early in the morning. This will help decrease the number of hours the leaf tissue remains wet and susceptible to infection. The frequency of irrigation is not as important as the time of day you do it. Don’t overfertilize and certainly don’t fertilize when brown patch is active. Also, don’t allow your seeding or overseeding rates to become too high.

Fungicide applications should begin in mid-June and continue through August. Often tall fescue lawns will recover from brown patch but infections this year seem more severe than usual and may require overseeding this fall. CLICK HERE to find the useful source for fungicides effective on brown patch.

Brown Patch on Tall Fescue

By: Ward Upham

(Article from June 30th, 2020 Horticulture e-Newsletter)

We have been receiving numerous reports of brown patch showing up on tall fescue. This disease is favored by warm night temperatures and extended periods of leaf wetness. If you go outside in the morning and the lawn is covered with dew and the temperature is in the high 60s or higher, it means that conditions are getting right for brown patch. The fungus is primarily a leaf pathogen and does not attack the roots. During severe outbreaks, the fungus may invade the lower leaf sheaths and crown and kill plants. But in most cases, the turfgrass can recover from brown patch. This recovery may take two to three weeks, depending on weather. To read more, visit the Horticulture e-Newsletter: https://hnr.k-state.edu/extension/info-center/newsletters/2020/June30_2020_26.pdf

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.

Brown Patch Resources

(By Jared Hoyle, KSU Turfgrass Research and Extension)

Tall fescue [Festuca arundinacea Schreb.] is one of the most predominantly used cool-season turfgrass species in the transition zone. Its deep root system and coarse textured leafs lend to its ability to withstand drought, heat, and wear stress. Although it is well adapted to survive the summer months in Kansas, it can be susceptible to injury from disease. Brown patch [Rhizoctonia solani] is a disease that can damage leaf tissue, shoots, and the crown of tall fescue during the summer months. This disease is most prevalent during periods of high humidity, high temperature (above 80°F), and high nitrogen levels. During the mornings mycelia can be seen forming a “smoke ring” around the affected area. Applications of preventative fungicides have proven to be a successful management strategy in reducing the occurrence of brown patch incidences in tall fescue stands.

Here are some resources from the past about brown patch!

Last year Dr. Fry was seeing brown patch in May.  With moisture and warm nights brown patch can start to develop.  https://blogs.k-state.edu/turf/im-not-ready-to-be-thinking-about-brown-patch-jack/

There are many products out there for brown patch control in turfgrass.  Which one is right for you.  Here is a quick update on research that was conducted at Olathe on some brown patch products. https://blogs.k-state.edu/turf/best-way-to-get-your-turf-noticed-brown-patch/ 

Do you know what brown patch looks like?  Do you know how to tell the difference between turfgrass stress and the disease.  Dr. Kennelly can show you the difference. https://blogs.k-state.edu/turf/is-this-brown-patch/

K-State Publications

Commercial Management of Brown Patch – https://www.bookstore.ksre.ksu.edu/pubs/EP146.pdf

Homeowner Management of Brown Patch – http://www.plantpath.k-state.edu/extension/documents/turf/Brown%20patch%20%20homeowners%202016.pdf

Best way to get your turf noticed? – Brown Patch!

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

Megan posted last week about brown patch already showing up at Rocky Ford Turfgrass Research Center in Manhattan, KS. So I wanted to share a little bit of research we conducted last year in Olathe about brown patch control. This way you know what to have ready to go when you need to make your brown patch application.

Rationale. Tall fescue [Festuca arundinacea Schreb.] is one of the most predominantly used cool-season turfgrass species in the transition zone. Its deep root system and coarse textured leafs lend to its ability to withstand drought, heat, and wear stress. Although it is well adapted to survive the summer months in Kansas, it can be susceptible to injury from disease. Brown patch [Rhizoctonia solani] is a disease that can damage leaf tissue, shoots, and the crown of tall fescue during the summer months. This disease is most prevalent during periods of high humidity, high temperature (above 80°F), and high nitrogen levels. During the mornings mycelia can be seen forming a “smoke ring” around the affected area. Applications of preventative fungicides have proven to be a successful management strategy in reducing the occurrence of brown patch incidences in tall fescue stands. With new fungicide formulations coming out every year, testing is needed to demonstrate the efficacy of these fungicides in reducing potential injury from disease.

Objectives. Evaluate Heritage Action and Velista for preventative control of brown patch in a perennial stand of tall fescue.

Study Description. A field study was initiated 18 June 2015 at the Kansas State University Olathe Horticultural Research Center in Olathe, KS on turf-type tall fescue maintained at 3 inch. Study was conducted as a randomized complete-block design, with three replications. Fungicides applied during this study were Heritage Action (Azoxystobin and Acibenzolar-S-methyl) and Velista (Penthiopyrad). Field study consisted of: an untreated control, Velista applied at 0.3 and 0.5 oz/1,000ft2, and Heritage Action applied at 0.2 oz/1,000ft2. Visual percent brown patch incidence was rated on a 0 to 100% scale every three weeks beginning at trial initiation. Means were separated according to Fisher’s Protected LSD test when P ≤ 0.05.

Table 1. Percent brown patch incidence on tall fescue with the application of preventative fungicides.
% Brown Patch Incidence†
Treatment 0 WAT‡ 3 WAT 6 WAT 9 WAT
Control 0 0 43.3 a§ 13.7
Velista 0.3 oz/1,000ft2 0 0 5.0 b 14.3
Velista 0.5 oz/1,000ft2 0 0 6.7 b 5.3
Heritage Action 0.2 oz/1,000ft2 0 0 0.0 b 0.3
† Percent brown patch incidence was visually rated on a 0-100% scale where 0% = no brown patch observed and 100% = plot completely affected by brown patch.
‡ Indicates weeks after treatment application.
§ Means in a column followed by the same letter are not significantly different according to Fisher’s protected LSD test, (P<0.05).

Results. All applications of the preventative fungicides resulted in minimal observations of brown patch. Six weeks after treatment application (WAT) Velista applied at 0.3 oz/1,000ft2 and 0.5 oz/1,000ft2 and Heritage Action resulted in 5%, 7%, and 0% brown patch incidence, respectively, when compared to an untreated control (43% brown patch incidence)(Table 1). Heritage Action performed best during this study with brown patch only being observed 9 WAT (0.3%). From this research, to decrease the chances of a brown patch incidence, apply a preventative fungicide before conditions are favorable for this disease. Repeat applications may be needed to ensure seasonal coverage.

 

 

brownpatch plots

Figure 1. Digital images of research plots 9 WAT, see Table 1 for the mean percent brown patch cover for each corresponding treatment.

More info on physiological decline and diseases

(By Jared Hoyle; KSU Turfgrass Research and Extension)

One of my good friends on the other side of the river at the University of Missouri, Dr. Lee Miller, has posted some great information about physiological decline and updates on diseases that he has been seeing.

For more information on physiological decline/ wet wilt of bentgrass greens check this out – “Summer Rises” – (It’s at the bottom of the article)

http://turfpath.missouri.edu/reports/2015/update07_13_15.cfm

For more information on diseases and more specifically brown patch control see Dr. Miller’s most recent post – “Rhizoc, Rinse, Repeat” –

http://turfpath.missouri.edu/reports/2015/update07_28_15.cfm

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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

 

Recent turf problems – a few photos

(Megan Kennelly, KSU Plant Pathology)

It’s mid-July, and much of Kansas continues to be pretty wet. Here are some recent turf issues I’ve been seeing and hearing about. I won’t go into details – this is just a photo collection for now.

(1)Brown patch in tall fescue lawns.

When you get all sweaty just from dragging the trash can down the driveway out to the curb on trash day, you know it’s brown patch season. Here are some symptoms in my neighborhood.

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(2) Summer patch

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Summer patch is a root disease of Kentucky bluegrass. Infection occurs in the spring, when soil temperatures hit 65. Symptoms pop out in mid-summer, when those poor plants with their compromised root systems just can’t take it anymore.

(3) Dollar spot

Sometimes dollar spot checks out during the summer, if conditions are hot and dry. We’ve had enough warm/wet weather to keep it rolling. Here are some photos in Kentucky bluegrass as well as in creeping bentgrass, especially in highly susceptible varieties.

dollar spot in low and hi cut029 028

(4) And, “it’s not a disease”

Turf sites with heavy clay soils, low areas with poor drainage, and shady sites = high stress. I received a sample the other day with some of the heaviest clay I’ve seen in awhile. It was so clay-ey that I took a moment to sculpt it into this little soil person:

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If your soil is heavy enough to use in art projects, you may have a problem. As you look forward to fall, think about aerification, drainage improvements, reducing shade, and other practices to improve conditions in tough sites.

A rainy spring meets a rainy summer. A cornucopia of turfgrass diseases

(Megan Kennelly, KSU Plant Pathology)

We are at the junction/transition of spring to summer. Large patch is still raging in the zoysiagrass. Dollar spot is active in bentgrass and other susceptible turfgrasses, especially in susceptible varieties. In addition, we’ve had some nights with lows in the upper 60’s or low 70’s, and that can mean brown patch activity. It’s a busy time for diseases. As one of my colleagues said, “It’s a fungusy sort of year here in Kansas.”

With all the rain, it’s been hard to keep up with the mowing. We are feeling it at Rocky Ford, with Cliff and the students busy mowing whenever they can sneak it in. And, it’s hard to spray fungicides when it rains every other day. I put out a trial this past Monday since it was the only day that looked clear. Good thing it was not on the agenda for yesterday, when we had 3 thunderstorms in the same day!

Large patch is still rolling in the zoysia:

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Dollar spot is active:

dollar spot

Brown patch might not be far behind:

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With all the wet, saturated soils there could by Pythium root rot as well:

Copy of pythium-bentrass-2006

(Pythium spores stained pink in the microscope).

As a final note, I’ve gotten some questions and photos recently about algae.

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Like other weeds, algae likes to take advantage of thinned out turf. Saturated soils and poor root growth can thin out the turf, and algae loves wet conditions. If you didn’t know where your drainage problems were, algal growth can point the way. There are some fungicides labeled for algae, but addressing the underlying site issues is key.

For a list of fungicides for algae, check HERE and go to page 7.