Category: Turfgrass News
By Dr. Jack Fry
Crabgrass is now becoming quite visible. If you didn’t apply a preemergence herbicide, or had some crabgrass emerge even where it was applied, now is the time to consider postemergence control. If a preemergence herbicide was applied, but you’re still seeing crabgrass, there may have been variability in uniformity of delivery over the area to which it was applied. If new sod was laid recently, it’s common for crabgrass to emerge through the seams. Control is easier when plants are young, for they are rapidly growing and have a thinner leaf cuticle. Make sure the crabgrass plant isn’t under stress before you apply the herbicide; rainfall or irrigation on the area within a few days prior to application can help ensure the herbicide is absorbed and translocated. Dr. Hoyle wrote a nice summary of best approaches to postemergence crabgrass control here: https://blogs.k-state.edu/turf/postemergent-crabgrass-control
In addition, consider purchasing Turf Weed Control for Professionals, which was developed by cooperatively by numerous universities in the Midwest, including K-State. It can be purchased as a hard copy or a PDF download here: https://mdc.itap.purdue.edu/item.asp?Item_Number=TURF-100
By Dr. Jack Fry
Below-average spring temperatures and a lot of cloud cover haven’t been beneficial for growth of warm-season grasses. Nevertheless, days are getting longer, and Meyer zoysia began to produce seedheads in northeast Kansas last week. Significant work was done at K-State on zoysia seedhead suppression by Dr. Jared Hoyle, along with Dr. Aaron Patton at Purdue University. Seedheads on Meyer have a purple tone to them, but after mowing, the seed stalks leave an undesirable white cast on golf course fairways and tees. The plant growth regulator ethephon (trade name Proxy) is effective at suppressing zoysia seedheads if it is applied at the proper time the previous autumn. Manoj Chhetri, a current Ph.D. student, is working on better refining application time for Proxy to suppress zoysia seedheads. The Golf Course Superintendents Association of America, along with the Heart of America Golf Course Superintendents Association and Kansas Turfgrass Foundation, are sponsoring this zoysia seedhead suppression research that is summarized in Golf Course Management magazine (link below).
By Dr. Jack Fry
After a productive seven years that provided a foundational learning experience not only for my personal growth but also professional growth, I will be joining Corteva Agriscience on March 30, 2020, as a Turf and Ornamental Territory Manager serving Colorado, North Dakota, South Dakota, Nebraska, Missouri and most importantly continuing to serve the great state of Kansas. This decision was not taken lightly given the high quality and professional expectations of the faculty, staff, and students at Kansas State University and additionally the continued commitment to the advancement of the turf industry by the incredibly talented and supportive professionals in Kansas. The current and future professional opportunities at Corteva are ones that my young growing family could not decline. Along with the professional factors, this opportunity provides my wife, daughter and me the ability to continue to grow in Manhattan with the increased flexibility as to where we live in the future. Interim Department Head, Dr. Steve Keeley, is currently working with upper administration in addition to the KSU Turf Team to ensure that the responsibilities associated with my position as Associate Professor as well as my responsibilities as the Rocky Ford Turfgrass Research Center Director be delegated to the appropriate party and peoples. I cannot reiterate enough how appreciative I am to everything Kansas State University has provided me through the years. From tenure and promotion to Associate Professor to an open and welcoming environment to improve my leadership skills and finally but most importantly by providing a “second family” as I began my career and family thousands of miles away from my immediate family. I believe that specific openness and welcoming support of the turf industry in Kansas and surrounding states will help continue the success of the Kansas State University’s turf program. Thank you for the last seven years! I will always be grateful for the memories made at Kansas State University.
-Jared Hoyle, Associate Professor, firstname.lastname@example.org
By: Brooke Garcia
NC State recently wrote up an article called, “Are Changes Coming for Atrazine and Simazine?”
Both Atrazine and Simazine were reviewed in 2013, and there are proposed changes for using each of these. To learn more, visit the article.
Full Reports for each pesticide can be found in the following links:
By Brooke Garcia
Meet Dani McFadden!
Dani McFadden is currently enrolled at Kansas State University pursuing her M.S. in Turfgrass Science, with an emphasis in Weed Science. She anticipates graduating in May 2021.
McFadden also holds an undergraduate degree from K-State in Horticulture, with a focus in Golf Course and Sports Turf Management.
When outside of class, McFadden loves walking around golf courses, sports fields, and home lawns to apply what she is learning in school. She enjoys being able to identify weeds and common diseases, as well as applying her knowledge of herbicides and fungicides.
McFadden’s favorite hobbies include playing golf with friends, fishing, and attending sporting events. More specifically, she likes attending sporting events that are played on natural grass.
Research Focus: Testing Labeled Restrictions on Seeding Timings after Herbicide Application
Here is what McFadden has to say about her research…
“Many people want to know when they can seed their lawn after herbicide application. Most labels restrict seeding until 2-4 weeks after application. My research includes seeding a stand 0, 3, 7, and 14 days after herbicide application along with the effects of different irrigation amounts on seedling germination. I am also doing research on tall fescue conversion to buffalograss after glyphosate applications.”
What’s next for Dani McFadden?
McFadden will always love mowing greens in the early morning while watching the sunrise. This is something she hopes everyone will have the chance to do. Looking ahead, she hopes to start a career with a chemical company as a territory manager. Through networking, she can continue to connect with great superintendents and turf managers in this industry. The “people in this industry is what makes being a turfgrass student so great,” says McFadden.
By Dr. Jack Fry
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.
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 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 superintendents managing golf courses:
Apparently, in Japan, golfers play year-round regardless of temperature. Some courses ignore frost to sustain income and have had less damage than expected:
Dr. Chase Straw, Turfgrass Scientist at the University of Minnesota, informed us of the recent release of a free soil moisture mapping protocol that can be utilized by golf course superintendents to assist them with fairway irrigation decisions. The protocol explains how to collect GPS soil moisture data with a commercially available device (FieldScout TDR 350), which are then used to generate fairway soil moisture maps with free software. The maps could be used as a tool to program an irrigation system to irrigate based on the soil moisture variability across a golf course, among possibly many other things.
More information about the protocol, in addition to details regarding how the Minnesota Golf Course Superintendents Association of America chapter is utilizing it as a service to their members, can be read from a recent blog post on the UMN turfgrass website.
The protocol can be downloaded here.
The protocol requires a $0 licensing agreement. FREE!!! Should you have any questions, don’t hesitate to reach out to Dr. Chase Straw (email@example.com) and his team at the University of Minnesota.
Minimal Water Requirements of Cool-Season Turfgrasses for Survival and Recovery After Prolonged Drought
Mu Hong, Dale Bremer, and Steve Keeley
Thermal Imaging Detects Early Drought Stress in Turfgrass Utilizing Small Unmanned Aircraft Systems
Mu Hong, Dale J. Bremer, and Deon van der Merwe
High and Low Management Input Regimes Result in Similar Net Carbon Sequestration Rates in Zoysiagrass Golf Course Fairway Turf
Ross C. Braun and Dale J. Bremer
Herbicide and Application Timing Effects on Windmillgrass (Chloris verticillata) Control
Nicholas Mitchell and Jared Hoyle
Influence of Herbicide Combinations and Sequential Applications on Windmillgrass (Chloris verticillata) Control
Nicholas Mitchell and Jared Hoyle
Winter Survival of Experimental Bermudagrasses in the Upper Transition Zone
Mingying Xiang, Jack Fry, and Yanqi Wu
Evaluating Large Patch-Tolerant and Cold Hardy Zoysiagrass Germplasm in the Transition Zone
Mingying Xiang, Jack Fry, and Megan Kennelly
2017 National Turfgrass Evaluation Program Perennial Ryegrass Test: 2018 Data
Mingying Xiang and Jack Fry