Turfgrass Epistemology

In this video, I examine the 2021 study by Beckley and Roberts published in the International Turfgrass Society Research Journal titled “Utilizing Organic Amendments for General Suppression of Dollar Spot on Creeping Bentgrass.” The discussion centers on one key question: Does biochar actually reduce dollar spot? I break down the experimental design—how researchers compared biochar, compost, vermi...

In this video, I explore the recent review article “Review of the Biology and Management of Large Patch of Warm-Season Turfgrasses” (Kreinberg et al., Crop Science, 2025). I walk you through what the authors tell us about Rhizoctonia solani AG 2-2 LP — the fungal pathogen behind large patch disease in warm-season turfgrasses — how environmental conditions favor its development, and how it can pers...

In this video, I take you through the state of the science on dollar spot disease in turfgrass, framed by the recent review “New Approaches to an Old Problem: Dollar Spot of Turfgrass.” We explore how this ubiquitous fungal disease (caused by Clarireedia spp.) continues to challenge turf managers, why traditional fungicide programs are increasingly under pressure, and what new genomic tools and br...

In this video, I dive into the article “Survey of Water Use and Management Practices on US Golf Courses from 2005 to 2024” published in HortTechnology (Shaddox et al., 2025). The study tracks nearly twenty years of changes in how golf courses across the United States use and manage water. I discuss how irrigation volumes and irrigated areas have shifted over time, highlight important regional diff...

In this video, I discuss the YouTube episode “Struggling Turf? Calcium Could Be the Missing …” and examine it through the lens of the strawman fallacy. We’ll look at how someone can present information that is technically true, yet still mislead by reframing the issue or knocking down an argument no one actually made. This breakdown shows how a conman can be both truthful and deceptive at the same...

In this video, I review the scientific article “Irrigation Frequency Affects Zoysiagrass Rooting and Plant Water Status.” We’ll look at how different irrigation schedules influenced root development and water relations in zoysiagrass, and what these findings mean for turfgrass management. If you’ve ever wondered how often you should water to encourage deeper roots and better turf performance, this...

In this episode, I break down the claims made in “Check out These Roots, John Perry! | [LIVE PODCAST] Ep.8 of the Average Joe Lawn Care Show,” where the hosts argue that liquid aeration is an effective solution for lawn health. I dive into the science and present evidence that challenges their assertions. With years of turfgrass science experience, I explain why liquid aeration doesn’t deliver the...

In this video, I take a look at some of the recent comments and questions from TikTok and YouTube. Your feedback not only shapes the conversations we’re having here but also sparks deeper discussions about turfgrass science and management. I’m also excited to introduce a new fundraiser supporting turfgrass research. Turfgrass plays a vital role in sports, recreation, and landscapes, yet research i...

In this video, I explore the findings of the research article “Tall Fescue Rooting as Affected by Deficit Irrigation” (HortScience, Volume 42, Issue 3). The study, conducted by Jinmin Fu, Jack Fry, and Bingru Huang and published June 1, 2007, investigates how reduced irrigation impacts the rooting behavior of 'Falcon II' tall fescue grasses using minirhizotron imaging. I’ll walk through: The study...

In this video, I examine the research by Cain et al. (2022) that explores how varying irrigation schedules affect the encroachment of annual bluegrass (Poa annua) into perennial ryegrass turf systems in western Oregon. The study reveals that watering once per week significantly reduces annual bluegrass encroachment compared to irrigating four times a week, and that replacing irrigation volumes bas...

In this video, I discuss the scientific article "Irrigation Rates and Frequency Affect Tall Fescue Color and Weed Encroachment." We’ll examine how adjusting irrigation amounts and timing influences turfgrass aesthetics and weed pressure. From water conservation to maintaining turf quality, this study provides valuable guidance for anyone managing tall fescue under variable moisture conditions. htt...

In this video, I review the scientific article "Irrigation Frequency and Amount Effect on Root Extension during Sod Establishment of Warm-season Grasses." We’ll explore how different irrigation strategies influence root growth during establishment, what this means for practical turfgrass management, and how to strike the right balance between watering efficiency and sod performance. If you manage...

In this video, I offer commentary on the scientific article titled "Water use and performance of Kentucky bluegrass influenced by cultivar, irrigation practices, and soil texture," published in the International Turfgrass Society Research Journal (DOI: 10.1002/its2.200). The study evaluated two Kentucky bluegrass cultivars, Mallard and Geronimo, grown in lysimeters filled with either loamy sand or...

In this video, I dive into the 2002 study from Crop Science that evaluates how different irrigation schedules, tall fescue cultivars, and mowing heights interact to shape turf performance. Article: https://acsess.onlinelibrary.wiley.com/doi/full/10.2135/cropsci2002.2011 ✅ What you'll discover: Study design highlights: 2‑year field trial in Riverside, CA, comparing 2–4 irrigation events per week a...

In this video, I respond to the Bermuda Grass Central video “The Best Summer Fertilizer for Lawns? Why Yard Mastery 7‑0‑20 is …”. I break down their main arguments, evaluate their fertilizer recommendations, and highlight both strong and weak points. ✅ What you’ll get: Summary of Claims: A quick overview of the video’s main points—why the creator supports Yard Mastery’s 7‑0‑20 blend for summer tu...

In this video, I critique “Found the Best Iron to Apply to Your Lawn For Summer Color” by a former golf course superintendent. While I agree that iron can boost turf color without pushing growth, I question some of the application advice—especially the dosing schedule and lack of soil pH context. I break down what the original video gets right, what it misses, and share my evidence-based tips for...

In this video, I break down the findings from the scientific article "Optimizing Irrigation Rates and Frequency for Perennial Ryegrass in Western Oregon." We’ll look at how different irrigation strategies affected turf quality and what this means for managing ryegrass under Pacific Northwest conditions. Whether you’re a turf manager or a lawn care enthusiast, this research has practical takeaways...

On this episode of Turfgrass Epistemology, Dr. Dan Sandor joins me to break down his study that addresses one of the most commonly misunderstood aspects of turf establishment: how much water should you really apply when seeding a new lawn? Sandor et al. (2021) evaluated daily irrigation at 50%, 75%, 100%, and 125% reference evapotranspiration (ETo) to determine how quickly tall fescue and bermudag...

In this episode of Turfgrass Epistemology, we dive into a study from Oregon State University that looked at how turfgrass species and mowing height affect water requirements in western Oregon. The results might surprise you—tall fescue and perennial ryegrass significantly outperformed fine fescues when it came to conserving water. We’ll break down the data on evapotranspiration replacement, irriga...

In this episode, I dive into the comment section and my inbox to respond to the most interesting, insightful, and downright puzzling messages I’ve received from viewers. From soil test questions and fertilizer theories to passionate turf debates and a few questionable product claims—nothing is off limits. Whether you're here to learn, laugh, or just see if your message made the cut, this video is...

In this episode, I dive into the comment section and my inbox to respond to the most interesting, insightful, and downright puzzling messages I’ve received from viewers. From soil test questions and fertilizer theories to passionate turf debates and a few questionable product claims—nothing is off limits. Whether you're here to learn, laugh, or just see if your message made the cut, this video is...

In this video, I critically examine the advice presented in "How to Fertilize in Hot Weather. Dog urine spot prevention, fungus recovery, general fertilizer." While the original video offers practical tips on lawn care during hot weather, it's essential to scrutinize the recommendations to ensure they align with best practices and scientific understanding. Key Points Discussed: - Fertilizing in Hi...

In this episode of Turfgrass Epistemology, we analyze a pivotal field study that tested the drought resistance and irrigation needs of five common turfgrass species under real-world conditions in northern Texas. Using a unique linear gradient irrigation system, Qian and Engelke evaluated how ‘Tifway’ bermudagrass, ‘Meyer’ zoysiagrass, ‘Rebel II’ tall fescue, ‘Prairie’ buffalograss, and ‘Nortam’ St...

He flashes university research to sell Air 8—but is it the whole story? In this video, I break down the science he didn’t show you. Liquid aeration sounds impressive, but does the data actually support the hype? Let’s dig into what the university study really says—and what he conveniently left out. If you're serious about turfgrass and tired of marketing spin dressed up as science, this one's for...

Which Grass Survives Water Restrictions? Science Has the Answer. On this episode of Turfgrass Epistemology, we dive into a long-term study that puts warm-season turfgrasses to the test under real-world municipal water restrictions. Which species held up best when irrigation was limited to once or twice a week? How do turf quality, coverage, and drought resilience stack up over time? Join me as we...