Kansas State University

search

K-State Turf and Landscape Blog

Planting Buffalograss and Controlling Weeds

By PhD student Dani McFadden, and Jack Fry, Professor and Commercial Turf Extension Specialist

Are you thinking about converting an area to buffalograss? It is a warm-season grass native to Kansas and much of the Midwest, with excellent heat, drought, and cold tolerance.  It is important to understand the characteristics of your site before determining if buffalograss is an adequate fit. Buffalograss grows best in an area receiving morning sun, and 6-8 hours of sunlight throughout each day. It is recommended to not plant buffalograss in poorly-drained areas or sandy soils. For non-irrigated sites, planting is recommended in the spring once soil temperatures reach 55 F. An optimum seeding rate is is 1.5 to 2 lbs of buffalograss burrs (1 to 5 seeds in a burr) per 1,000 sq. ft.

Buffalograss is dioecious, which means there are male and female plants.  In seeded areas, you can see the inflorescences (male flowers) on male plants  emerge several inches tall.  The female plant produces a flower close the soil and is not as noticeable.  Ultimately, several seeds are produced within the female burr. There are vegetative buffalograss cultivars that can be purchased which are most typically plugged for establishment.  They are generally the female plants (no visible seedheads during the growing season).

You can learn more about cultivars, establishment, and management by using these links:

K-State “Buffalograss Lawns”: https://bookstore.ksre.ksu.edu/pubs/mf658.pdf

K-State Turf and Landscape Blog:  https://blogs.k-state.edu/turf/

National Turf Evaluation Program:  https://ntep.org/

For irrigated sites, you can delay seeding until June through July; early June planting enhances the potential for good coverage by the end of the growing season. Seed should have good contact with the soil – planting 0.25 to 0.5 inches below the soil surface is recommended.  For effective grow-in, any non-desired vegetative grasses or weeds should be removed from the area with the use of herbicides (check label to confirm time required before seeding can be done after application).

Converting an area to buffalograss can be costly and time consuming; therefore, it is important to protect the area from weed invasion. Weed control is critical during establishment, as many weeds are able to outcompete buffalograss seedlings. Mesotrione (Tenacity) is labeled for application at the time of seeding. Quinclorac (Drive XLR8) is also labeled for application any time before or after seeding buffalograss for the postemergence control of grassy weeds. Two combination products, SquareOne and Solitare, are labeled for use on established buffalograss for the control of a broad spectrum of weeds. If you are facing weed pressure, it is important to first identify the weed before purchasing the herbicide. For example, products containing quinclorac as a single active ingredient will control many grassy weeds, with minimal control of broadleaf weeds. You should always read the herbicide label for a detailed list of weeds controlled by the product, along with application rates and timings.

 

Winter Desiccation

By Dr. Jack Fry, Professor and Commercial Turf Extension Specialist

Winter desiccation on a creeping bentgrass green that had significant thatch accumulation.

Winter desiccation is a form of “winter injury” that can often occur in February and March during extended periods of dry weather. Most susceptible are seedlings that were seeded late in autumn, and established turf that has excessive thatch. If you seeded in late October and turf is not yet mature, consider applying water if we get into an extended dry period.  Lack of maturity means limited root growth and more frequent water is needed.

Creeping bentgrass is quite susceptible to desiccation, particularly when it accumulates some thatch.  In fact, winter desiccation injury often more common on fairway height turf that has accumulated thatch compared to that growing on putting greens.  Roots become elevated in the thatch and are unable to absorb water from soil.  Creeping bentgrass growing on elevated sites that are most exposed to wind is most susceptible.  Again, water application may be needed during extended dry periods to reduce the risk of desiccation.  This may required methods of water application other than just irrigation.  For example, sometimes boom sprayers are used to deliver water – multiple passes may be needed.  In areas where desiccation is common on bentgrass greens, it not unusual for superintendents to topdress heavily in the fall, or provide some kind of cover on the surface through winter – sometimes synthetic cover or using branches from cedar trees or other evergreens –  to help reduce wind effects.  Click links below for more information.

USGA article

Sportsfield Management article

 

Ice, Ice Baby

By Dr. Jack Fry, Professor and Turf Extension Specialist

Ice can cause many problems for turf, in various forms.

Ice Inside the Plant

Ice routinely forms inside plants when temperatures drop below freezing. Where the ice forms is important – when it’s outside the plant cells, it’s usually not an issue. This is called extracellular freezing.  However, no plant cell will survive when ice forms inside it.

The most important part of the turfgrass plant regarding survival is the crown, or growing point. Again, ice forming outside cells inside the crown is common and usually not harmful. It can become an issue, primarily in warm-season grasses, like bermudagrass, when temperatures are very cold for extended periods of time. This forces water inside cells to exit toward the ice (a matter of physics), and too much water leaving the cells will cause dehydration, which can cause the crown to die.

Freezing injury on bermuda is caused by ice forming outside cells within the crown of the plant that causes dehydration.

Ice formation inside cells of the crown commonly causes the death of grasses in the northern U.S, and it’s called intracellular freezing or crown hydration injury.  Usually, grasses that succumb to this type of injury become well hydrated in early spring, often growing in low areas that don’t drain well. Hydrated crowns that are then subjected to extremely low temperatures often suffer from ice formation inside cells of the crown;  when this occurs, they don’t survive. This is common in the northern U.S. on annual bluegrass on golf greens. It could also occur here, but would be most likely on warm-season grasses lying in low areas.

Ice Covering the Plant

Fortunately, in the central U.S., we don’t deal with extended periods of ice cover on turf. Ice cover can result from sleet, freezing rain, or snow melting and refreezing. Turf managers in the northern U.S. begin to worry about ice cover when it remains in place for about 60 days. That’s usually the limit for annual bluegrass – being under ice cover more than that can cause issues with lack of oxygen and/or accumulation of toxic gases under the ice

Ice on the Leaf Surface – Frost!

In a humid environment, when the leaf surfaces cool to temperatures below freezing, ice will form as frost on the leaves. Leaves of cool-season grasses tolerate frost on leaves just fine. Leaves of warm-season grasses don’t like frost, and we often see them go dormant shortly after the first hard frost in the fall.

Frost on the leaf surface can damage when foot or vehicle traffic causes the crystals to puncture the leaf cells (photo courtesy of Dr. Hoyle).

Frost is primarily a problem for turf managers in spring and fall on cool-season grasses. Foot or vehicle traffic pushes the ice crystals through the leaf surface and punctures cells, causing them to collapse. The result is that there is often brown turf where traffic was present. Honestly, I don’t think we know enough about the physics of ice that comprises frost, and I suspect that frost differs a lot – some ice forming on leaves may be more damaging than other ice.

Following are a few articles related to frost on turf.

For golfers:

https://www.usga.org/content/usga/home-page/articles/2018/01/5-things-to-know–frost-delays.html

For superintendents managing golf courses:

https://www.golfcourseindustry.com/article/golf-frost-delay

Apparently, in Japan, golfers play year-round regardless of temperature.  Some courses ignore frost to sustain income and have had less damage than expected:

https://www.blog.asianturfgrass.com/2016/12/how-to-lose-120-million-yen-with-frost-delays.html

Pushing Snow

Many of you are busy “pushing snow” with the recent cold weather, and there will likely be more snow to push in the next couple of months. Please take a few minutes to train your staff on protecting ornamental plants when clearing hard surfaces like parking lots.

While clearing the lot, driveway, or sidewalk is the most critical objective, “do no harm” should also be a goal. Far too many plants are crushed by the push and weight of snow in winter months. Sometimes, the mystery summer problem is actually a clear winter problem.

There is a tendency to pile snow on top of green spaces in parking lots. However, plants in those spaces continue to need to photosynthesize (evergreens) and exchange gases and are likely to die or suffer severe dieback if the cold weather persists and the snow takes a significant time to melt. Piling snow in planting areas can also contribute to soil compaction and root decline, causing problems later in the growing season.

De-icing chemicals are often mixed into snow that is pushed into landscape settings. As the snow melts, it dumps salt into the planting area, damaging shoots and roots for the long term. To minimize the landscape impacts of clearing snow, consider alternative de-icing salts like calcium chloride and calcium magnesium acetate and follow the label instructions when possible. Sand can also help provide traction.

With your staff, practice identifying an appropriate place to pile snow that isn’t in landscape areas, offers a place to collect runoff, and won’t result in slush that can splash onto plants. When possible, make these decisions before snow is on the ground—snow can cover a lot of detail and make it easy to lose track of the areas that need to be preserved.

Study each site individually and develop a plan for human, pet, and plant safety when winter storms hit to avoid problems in the future and establish trust with your clients.

Wind Chill Analysis Tool from Kansas Mesonet

By Christopher “Chip” Redmond, Kansas Mesonet Manager, via Agronomy eUpdates

The forecast for the coming week consists of bitter cold air, the coldest of the 2023/2024 winter season thus far. However, the temperature does not always give the air that nip. The “feels like” temperature is also usually influenced by the wind. We call this the wind chill.

What is the wind chill?

When temperatures drop below 50oF and wind speeds are greater than five mph, the “Feels Like” temperature is lower than the actual temperature. Wind chill can be calculated in two ways: 1) using the chart below or 2) mathematically. Wind chill values decrease as the wind increases and/or the temperature decreases. This means that despite it being 0oF on a very cold morning when factoring in the wind (for example, 20 mph), it can feel like a much colder temperature (in this example, -22oF).

This colder “feels like” temperature can make you feel chilled quicker and lead to other problems such as frostbite much quicker. Exposure time estimations of frostbite issues at 0 degrees F with no wind is 30 minutes, while 0oF and 55 mph winds are less than 10 minutes of exposure. Wind chills can be determined by the following chart from the National Weather Service (https://www.weather.gov/safety/cold-wind-chill-chart):

Where can you access wind chill data?

The Kansas Mesonet makes viewing the wind chill very easy! We have put together a webpage depicting the current wind chill via a gradient map here: https://mesonet.k-state.edu/weather/windchill/. It can also be accessed via the menu in the top left (Menu à Weather à Wind Chill)

The map defaults to the current wind chill but also has a selection at the top where you can change the map to view temperature and wind speed/direction. Since these are the two ingredients for the wind chill, it tells the complete story. The table below the map also displays each station’s wind chill, temperature, and wind data in sortable columns. By clicking the column headings, that particular column will sort from lowest to highest values. Click it again, and it will reverse the order. You can also select a specific station either on the map or in the data table, and it will display the specific information for that location.

How many hours has the temperature been below freezing?

Winter wheat and cover crop producers still have an interest in the cold temperatures. The freeze monitor data is available on our webpage as well. It allows you to track the hours below 32 or 24oF thresholds useful for permafrost development or winter wheat/cover crop damages.  You can access this information via the menu in the top left (Menu > Weather > Freeze Monitor) or at mesonet.ksu.edu/weather/freeze

Stay warm and safe on these chilly days! Winter has only just begun.

New 2023 USDA Plant Hardiness Zone Map Released

2023 Kansas USDA Plant Hardiness Zone Map

On November 15, the USDA released an updated Plant Hardiness Zone Map (https://planthardiness.ars.usda.gov/). The new map reflects data from significantly more weather stations, a sophisticated algorithm, and new tools designed to be interactive and internet-based. Users can now search by zip code for Plant Hardiness Zones detailed within a half-mile radius. New data reflects microclimates like urban heat islands and cold mountain tops.

For Kansas, most of the state shifted about a half zone warmer. We still have pockets of Zone 5 in the north, but the range of Zone 7 in the southern part of Kansas is more extensive. As industry professionals, we should continue to focus on recommending plants that can handle Zone 5 plant hardiness because we will continue to experience extreme weather events. However, many of the more southern communities in Kansas can also expand their plant palette with species originating in slightly warmer climates–horticulture is always an adventure with new-to-us species and cultivars. These zone changes may also reflect longer season extension for some food crops.

The USDA Risk Management Agency uses the USDA Plant Hardiness Zone Map to set crop insurance standards. Other scientists use the data in models that might indicate the spread of weeds, insects, or diseases.

It’s important to note that these warmer plant hardiness zones do not indicate global climate change. Data used for this map is extensive, about 30 years worth at over 13,000 weather stations, but it is not the required 50 to 100 years of data that will provide reliable evidence of global climate change. It simply reflects greater available detail, tools, and methods.

More information can be found at the USDA Press Release and Map Creation web pages.

We will work on reviewing and updating our plant recommendation publications for Kansas. Let us know if you have questions or thoughts–please reach out!

 

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.

Visit with Industry Representatives at the Kansas Turf and Landscape Conference Trade Show

Register for the Kansas Turf and Landscape Conference and chat with various turf and landscape industry exhibitors!

The 73rd annual Kansas Turfgrass and Landscape Conference, held November 29 & 30 (Wednesday and Thursday), 2023 at the Hilton Garden Inn, Manhattan also hosts a trade show to see all the latest products and supplies from local and national vendors.

Vendors will have a booth with representatives present for the following companies:

Interested in being part of the trade show as an exhibitor or as sponsor for the event? Register online or contact Christy Dipman for more information at cdipman@ksu.edu or 785-532-6173.