When hot dry winds meet hydrophobic (water-repellent) soil we can get “localized dry spot” in turf. The damage can develop quickly.
Water should wick in quickly. However, when the soil is hydrophobic the droplets sit there on the surface, and they don’t soak in:
The soil becomes hydrophobic due to a build-up of water-repellent waxy substances around the soil particles.
Here are some examples of what it can look like. It often takes odd shapes with unusual wispy/hazy edges:
Below are a couple of photos from a recent sample to the KSU diagnostic lab. You can see hydrophobic area a couple of inches down in the profile. You can also see the damaged turf in the background. The submitter said it was quite patchy around the green. It’s important to check your moisture levels regularly. When you do, check it in multiple places. You can even go high-tech with a moisture meter. For more information you can check this article from a few years back, Water Management on Greens With Soil Moisture Sensors.
Thatchy soils are one predisposing condition, and you can see the thatchy layers from this particular site here (though this particular plug was NOT hydrophobic):
Thatch management and wetting agents can help prevent and alleviate localized dry spot. There is some USGA info about localized dry spot here:
“This growing season may be a challenge for producers/applicators in more ways than one. With the critical need for N95 respirators for health care workers, it is anticipated that applicators may experience a shortage of personal protective equipment (PPE) that will be available to use this growing season if not previously purchased.”
The K-State Turf Team would like to give a heartfelt farewell, thank you, and best wishes to our friend and colleague Dr. Jared Hoyle.
As you saw in Jared’s recent message, he is leaving KSU to join Corteva Agriscience. We will miss Jared, but we are excited for him to pursue other opportunities. We are glad he’ll still be based in Manhattan, at least for now.
Jared joined KSU as an Assistant Professor and Extension Specialist in 2013. He was recently promoted to Associate Professor with tenure. He’s had an extremely productive academic record in both research and extension. Jared has been particularly active in social media, with more than 2,300 followers on Twitter and around 200 blog posts. He has created videos for KSRE, KSUTurf YouTube and other channels with more than 2,700 views. Jared has developed “flipped classroom” online resources to support the Extension Master Gardener Program. Jared also served a critical role as Director of the Rocky Ford Turfgrass Research Center in Manhattan. We will miss Jared as a KSU colleague, but we look forward to working with him in new ways.
Cheers and best wishes to Dr. Hoyle!
The KSU Turf Team
Megan Kennelly, Jack Fry, Steve Keeley, Dale Bremer, Christy Dipman
It is an unprecedented time at KSU. We are under highly limited on-campus operations due to the COVID-19 pandemic.
At present, only “mission critical/essential” functions are occurring on campus. Faculty, staff, and students are primarily teleworking from home. Courses have shifted to online-only, extension includes no face-to-face interactions until at least mid-May, and many research labs are essentially closed or running at very minimal levels. However, the KSU Turf Team is still here to support the industry as best we can while carefully following all the public health policies and guidelines.
Currently, much of our long-term turfgrass research is still operational at Manhattan (Rocky Ford Turfgrass Research Center), Olathe (K-State Olathe Horticulture Research & Extension Center), and Haysville (JC Pair Center) but under highly restricted conditions. We have developed Continuation of Operations Plans to work safely following all CDC guidelines and policies of our College of Agriculture and KSU. We have reduced time on-site to essential tasks only. The KSU Plant Disease Diagnostic lab is still open, but with some changes. Details can be found here.
The situation evolved very rapidly over the past 2 weeks, it is still evolving, and things could change.
In addition, our colleague Dr. Jared Hoyle is leaving KSU to take an exciting opportunity in industry. You can read Jared’s farewell here and our turf team message here. This is additional change for the Turf Team to navigate right now. We are in conversation with college leadership about this topic as well.
In the meantime you can reach us by email and phone.
As always, your local K-State Research and Extension Agent is a best first contact. You can click on this map to find your local office. Agents are also primarily teleworking due to the COVID19 situation but they are responding to email and phone.
Jack Fry: email@example.com, turf management questions from professionals. 913-353-6823 (cell)
Stay well and best wishes for good health to you and your families. We know many of you are affected both personally and professionally by the current situation. Our top concern is everyone’s health and well-being. Take care everyone.
It is an unprecedented time at KSU. We are under limited on-campus operations due to the COVID-19 pandemic.
At present, only “mission critical/essential” functions are occurring on campus. Faculty, staff, and students are primarily teleworking from home. All teaching has converted to online, and research operations have ramped down significantly. Mail and package delivery systems have changed.
Our plant diagnostic lab remains open. I will continue to work closely with Judy O’Mara on horticulture sector samples. Judy, as Director of the lab, provides this important update:
The KSU Plant Disease Diagnostic Lab continues to remain open at this time. However, we are working under limited operations and staff, so turn around may take a little longer than usual. There have been a few changes to our submission procedures. Please read the information below:
No in-person sample delivery to lab. Instead, if you are in Manhattan please use the soil drop box located on the Northwest side of Throckmorton PSC.
US Postal Service sample delivery to 4032 Throckmorton PSC 1712 Claflin Rd Manhattan, KS 66506 is still available, but will be checked at a minimum of twice a week. Time sensitive samples should NOT use USPS and instead use the new temporary address below for UPS/FEDEX.
The best mailing option for samples to the plant disease diagnostic lab is BELOW.
Please email us the tracking # so we know that a sample is coming to the lab.
Our NEW TEMPORARY MAILING ADDRESS for UPS/FEDEX packages
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.
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.
The University of Missouri recently held a Turfgrass and Landscape Field Day on July 30th, 2019 at their South Farm Research Center. They shared an update on their website, covering weeds, billbugs, diseases and bees.
Find more about their field day program in this link.