QUESTION: We asked experts from suppliers: What’s the most important thing to consider when diagnosing a turf disease correctly?
Jim Goodrich, Product Manager | PBI-Gordon
Your eyes and brain are probably the most important tools in diagnosing turf diseases. Look for visual signs. Spots or lesions on the grass plants help you identify the disease, and the actual disease structures can often be seen with the naked eye. For instance, the white mycelium of dollar spot is often visible in dewy morning turf.
Jill Calabro, Plant Pathologist | Nufarm
First, you need to identify an appropriate diagnostic lab. Most major universities will have extension services available and some will have dedicated turf disease diagnostic labs. North Carolina State University and the University of Wisconsin are two great examples. Some private groups also offer diagnostic services. Once you select a lab, consult them on how to prepare or select a sample. They can offer very good recommendations on what to do. When you send in a sample, send live plant tissue if possible, not just dead plants/turf. When you send in dead tissue, there are other microbes present that can confuse the diagnosis. For example, if you have a patch of diseased turf, collect a cup cutter plug from the expanding margin so you’re collecting healthy tissue and diseased tissue where the pathogen is most active.
Kyle Miller, Senior Technical Specialist | BASF
When correctly identifying turf disease, the most important factor to consider is current environmental conditions. Turf diseases largely depend on temperature, relative humidity and soil moisture, and most diseases have fairly specific environmental conditions under which they occur. If it’s mid-summer and turf disease is running rampant during high temperatures and humidity, it’s easy to rule out many diseases and focus on those that occur under those conditions. In addition to understanding the role of weather conditions, having a disease identification guide is key to properly identifying troublesome turf diseases.
Colleen Tocci, Marketing Manager | Engage Agro USA
Approach things methodically. If you can’t accurately identify the disease, you can’t properly treat it. Therefore, a complete assessment of turf variety, recent weather patterns (including rain/drought and temperatures) as well as recent maintenance and chemical applications should be conducted. Is the problem widespread or are there random patches? Are any other golf courses in your area experiencing similar symptoms? Once you have gathered all the information, utilize the resources available to you including your own expertise, university personnel, extension agents or disease specialists to help you properly diagnose and treat the disease.
Matt Giese, Technical Manager | Syngenta Turf & Landscape
The most important factor for correctly diagnosing a turf disease is familiarizing yourself with how diseases affect your specific turf type. By understanding which pathogens typically affect the turf type, the symptoms they express and the weather conditions that promote disease development, superintendents can implement prevention tactics to help manage diseases. It is also important to consider the micro-climate within the stadium or complex. Airflow, shading, sunlight duration, drainage and temperature extremes can all weaken the plant and affect disease development and/or severity, especially in stadiums. Additionally, recording previous disease outbreaks, watching for signs of the disease (mushroom structures, foliage pustules, etc.), and mapping the location of infection can help with future disease prevention.
Rob Golembiewski, Ph.D. | Bayer Green Solutions Team
There are two important things to consider when diagnosing a turf disease correctly: (1) determining which turf specie(s) is/are affected, and (2) reviewing the recent weather history (rainfall, day and night temperatures, etc.) of the site. A superintendent should be able to use this information to narrow the possibilities down to one or two key diseases. With this knowledge, and by observing the symptoms being exhibited, an accurate diagnosis can be made and appropriate cultural and chemical strategies implemented.
Ken Hutto, Technical Service Manager | FMC Professional Solutions
It’s important to understand environmental conditions at the time of initial disease onset. Many times, turf managers react only to what they see happening to the turf. Since different environmental conditions can trigger specific disease outbreaks, understanding which environmental conditions favor which disease development can be foundational for correct diagnosis of visual signs and symptoms present. For example, hot and humid conditions with extended periods of leaf wetness when temperatures are above 65 F at night often favor brown patch development. Correctly understanding favorable environmental conditions first and the relationship to specific disease onset will allow the turf manager to implement the most effective management practices to eliminate and hopefully prevent further disease development.