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K-State Turf and Landscape Blog

Author: Jack Fry

Thinking Ahead to Factors that Can Impact Freeze Injury of Warm-Season Grasses

 

Winter injury in certain areas where warm-season grasses grow in the transition zone is not unusual.  Specifically, here are the things that can have a significant impact on winter injury of zoysiagrass and bermudagrass:

 

 

 

  • Selection of a less cold hardy warm-season grass: There is a relatively short list of bermudgrass and zoysiagrass cultivars that are best adopted to the transition zone, including Kansas. Here are a few of each of those species that are relatively good through winter, but that doesn’t mean they can’t suffer winter injury:

Zoysiagrass Meyer, Innovation, Zenith (seeded), Chisholm

Bermudagrass Tahoma 31, Latitude 36, Northbridge, Yukon (seeded), Monaco (seeded)

 

  • High Nitrogen levels: High levels of nitrogen fertilizer through the growing season, or nitrogen applied in the fall can have a more significant impact on winter injury.

 

  • Shade: Shade reduces photosynthesis and carbohydrate production by grasses, and can significantly reduce the potential for a species/cultivar to survive cold temperatures.  Trimming trees or removing them may be required to enhance cold hardiness.

 

  • Traffic: Significant traffic on the soil and turf prior to winter can have a significant impact on the turf and result in higher levels of winter injury.  Traffic control (not allowing excessive traffic) and effective aerification can help enhance its survival.

 

  • Excessively wet soil: It’s not unusual for warm-season turf that sits in a low area (often on golf course fairways) where water accumulates can have a greater impact of winter injury.  High levels of water in the soil will impact these grasses when severe cold arrives.  Improved drainage can help protect these areas.

 

  • Lack of snow cover: Snow is very beneficial to protect warm-season grasses prior to excessively low temperatures.  For example, several years ago we had snow cover in Olathe, KS when temperatures were at least -15 F and no winter injury occurred.

 

  • Grass not fully acclimated for cold temperatures: There is a greater chance of freezing injury if temperatures get quite low when the grass had not fully acclimated to cold. Example – excessively low temperatures in November or December can have a significant impact.  Likewise, the same may occur during late winter or early spring when warmth approaches and then that is followed by excessive cold.

 

  • Exposure to wind on high level areas: This can often cause desiccation in winter if exposed to strong wind when there is no snow cover.  If expected in the near future, it may be useful to apply water on these elevated areas before the excessive cold arrives.  Or…some type of cover to protect the surface.

Round-Up Herbicide(s) No Longer Just Contain Glyphosate

For many years, Round-Up herbicide was recognized as a non-selective herbicide that contained glyphosate and was used to take out all vegetation.  Round-Up is now sold as multiple different products containing many different combinations of herbicides.  The University of Tennessee team recently composed a document that provides details on Round-Up.  All should pay close attention to active ingredients contained within each Round-Up herbicide now sold.

Details from Tennessee here:

UPDATE ON ROUND-UP BRANDED HERBICIDES FOR CONSUMERS

2024 Resources for Turfgrass Disease and Weed Control

 

 

 

 

 

Two separate documents have been released that are quite helpful for those needing specific information related to turf disease control and weed control.  Chemical Control of Turfgrass Diseases 2024 was recently released by Univ. of Kentucky, Rutgers Univ., and the Univ. of Wisconsin-Madison.  This is a cost-free document which you can access by clicking on the above link.

 

 

 

 

 

In addition, a new release for weed control was recently put out:  Turfgrass Weed Control for Professionals 2024 EditionPurdue University leads the changes in this weed information and over the years contributions have been made by those at universities in Illinois, Indiana, Iowa, Kansas (K-State), Maryland, Michigan, Minnesota, Missouri, Nebraska, New Jersey, New York, North Dakota, Ohio, Pennsylvania, and Wisconsin.  The link above will take you to access to this document which requires a low-cost purchase.  You can also find this available at the check-in table at the K-State Turf and Landscape Conference in December, 2024.

Conference Speaker Highlights: Dr. Chase Straw

We are fortunate to have three great out-of-state speakers join us at the Kansas Turf and Landscape Conference this year.  These individuals include Matt Cavanaugh, golf course superintendent in MN; Dr. Chase Straw, Assistant Professor at Texas A&M Univ.; and Dr. Aaron Patton, Professor at Purdue Univ.  Dr. Chase Straw is highlighted here.  Chase will have the following presentations: “Be Precise – Reducing Water in Fairways with Precision Irrigation”; “Spray Application Technology in Turf and Landscapes”; “Field Variability and Its Impacts on Athletic Field Surface Interactions”; “Dealing with Natural and Synthetic Turf – Panel Discussion.”

View the program and mail the completed the paper registration form with payment OR you can register online at: https://2023turfandlandscapeconference.eventbrite.com
You receive a discounted rate if you register before November 22.   Sponsorship Opportunities are also available.

Conference Speaker Highlights: Matt Cavanaugh

We are fortunate to have three great out-of-state speakers join us at the Kansas Turf and Landscape Conference this year.  These individuals include Matt Cavanaugh, golf course superintendent in MN; Dr. Chase Straw, Assistant Professor at Texas A&M Univ.; and Dr. Aaron Patton, Professor at Purdue Univ.  Matt Cavanaugh highlighted here – more information on others coming soon.  Matt will have the following presentations:  “Work is Hard – Why Not Have Some Fun!”; “No Mow Fine Fescue Areas – What Works and What Doesn’t;” “You’re Doing What?”

View the program and mail the completed the paper registration form with payment OR you can register online at: https://2023turfandlandscapeconference.eventbrite.com
You receive a discounted rate if you register before November 22.   Sponsorship Opportunities are also available.

 

Conference Speaker Highlights: Dr. Aaron Patton

We are fortunate to have three great out-of-state speakers join us at the Kansas Turf and Landscape Conference this year.  These individuals include Matt Cavanaugh, golf course superintendent in MN; Dr. Chase Straw, Assistant Professor at Texas A&M Univ.; and Dr. Aaron Patton, Professor at Purdue Univ.  Dr. Aaron Patton is highlighted here.  Aaron will have the following presentations:  “The Impact of Spray Tank Water on Pesticide Performance”; “Identifying and Controlling Tough Broadleaf Weeds”; “Growing Turf in Low-Light, Shaded Environments”; “How to Handle Excessive Shade on the Golf Course” (Panel Discussion).

View the program and mail the completed the paper registration form with payment OR you can register online at: https://2023turfandlandscapeconference.eventbrite.com
You receive a discounted rate if you register before November 22.   Sponsorship Opportunities are also available.

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.

Two-minute Turf Extension Video: Upcoming Field Day Highlights

A brief overview of a few stops that will be seen at the Olathe Horticulture Research Center can be found on the this video.  We look forward to seeing you at the Olathe Center on August 3rd!

 

CLICK HERE to see the video that provides an overview of the Field Day!

Register for Field Day using the QR code below or visiting https://2023turfday.eventbrite.com

Robotic Mowers

 

Robotic mower use is becoming more popular.  I was fortunate to recently visit with Steve Wilson, certified golf course superintendent at Milburn Country Club, about use of robotic mowers at his course.  Steve uses 11-inch wide robotic mowers that cover areas near greens and tees on the golf course.  He uses several of them to cover about 15 acres.  They are controlled by a reference station which connects with a satellite.  Areas to be mowed are defined by the manager and the mowers can operate over up to 24 hours.  When the lithium battery gets low, the mowers return and automatically connect to a charger – no person needed to connect!

We have a lot more to learn about robotic mowers and how they’ve performed for those in the industry.  We’ll have an industry discussion session at the 2023 Kansas Turf and Landscape Conference (Nov. 29 and 30th in Manhattan, KS) involving Steve and others who use or market robotic mowers.

Click here to view robotic mower in use.

Webworms Causing Damage to Turf this Spring

Although referred to as the “buffalograss webworm” this insect has the ability to cause damage to cool-season and warm-season turf.  Dr. Raymond Cloyd has had been reached out to help from many in the industry regarding damage to lawns this spring.  Learn more about this insect issue by clicking on the link below and then clicking on Newsletter>2023:

DR. CLOYD’S RECENT K-STATE INSECT NEWSLETTER ARTICLE