The UF/IFAS North Central Florida Turfgrass Field Day at the Plant Science Research and Education Unit (PSREU) in Citra last Wednesday was highly valuable, a testament to the UF/IFAS Turfgrass Sciences Program’s unwavering century-long dedication to research and education. It served as an outstanding representation of the UF Turf Team’s commitment to impactful outreach.
The day began with crisp morning air and a light sprinkle, gradually giving way to late-morning breezes under persistent sunshine. The ideal weather conditions provided the perfect backdrop for an event that brought together more than 300 professionals across the turfgrass industry.
Beneath the pavilion bordered with tables from industry vendors and bustling with talkative representatives, the smell of a delicious BBQ simmering wafted through the air, exciting our bellies for what was to come. Amidst this inviting scene, UF/IFAS’s Dr. Jason Kruse, Associate Professor of turfgrass science, Dr. Jerry Fankhauser, Assistant Director of the Florida Agricultural Experiment Station, and Jim Boyer, Director of Research at PSREU, greeted attendees who had gathered in preparation of embarking on one of two exciting tours. These tours were thoughtfully designed to cater to specific interests, one focusing on golf and athletic field management and the second tailored to residential and commercial lawn care.
I chose the golf and athletic field maintenance tour, and although I wish I could have participated in both, I was satisfied with my decision. I eagerly jumped on the first bus that pulled up to the pavilion. The enthusiastic bus driver, meandered around the many research plots at the PSREU, eventually dropping us off at our first stop, starting our three-hour walking field tour across the turfgrass research field trials.
Stop 1: Management of Key Insect Pests on Golf Course Turf, Dr. Adam Dale
Dr. Adam Dale, an entomologist specializing in turfgrass at UF/IFAS, equipped with vials and boxes of pinned insect pests, led a lively field presentation focusing on the prominent insect pests plaguing Florida’s golf courses and athletic fields. He stressed the pivotal role of sound cultural practices in maintaining turf health as the primary defense against these pests. Dr. Dale’s innovative program delves beyond direct pest control, striving to comprehend why certain insects become nuisances and proactively addressing those root causes. During his discussion, Dr. Dale polled the audience for their most pressing pest concerns, which included billbugs, mole crickets, and even chinch bugs infesting seashore paspalum – a surprising revelation.
Regarding mole crickets, Dr. Dale emphasized the importance of managing soil moisture levels, as these pests thrive in wet conditions. However, the good thing, he explained, is that higher soil moisture means mole crickets reside closer to the surface, making them more accessible targets for control. Additionally, he noted their nocturnal behavior and attraction to light, suggesting that removing lights can help curb their movement.
Regarding billbugs (beetles with snouts aka weevils), Dr. Dale clarified a common misconception regarding their feeding habits, debunking the notion of being sap-sucking pests. He described that under that snout there are chewing mouthparts and all life stages, except the pupae, feed on all turf plant parts. He highlighted the importance of early treatment, particularly in spring, to minimize damage that becomes more apparent in winter. Utilizing pitfall traps for scouting and employing specific chemical control options when necessary were recommended practices for effective pest management.
Stop 2: Strategies for the Postemergence Control of Goosegrass, Mikerly Joseph
Mikerly Joseph, a Ph.D. student with UF/IFAS turfgrass weed scientist Dr. Pawel Petelewicz, discussed his project on improving goosegrass management strategies. Mikerly’s poster highlighted his greenhouse trial efficacy research data using topramezone on mature goosegrass populations. The objectives of his study were to identify the minimum rate of topramezone required for successful control of mature (tillering) goosegrass plants and evaluate multiple, frequent applications of minimized topramezone rates to control goosegrass populations. His preliminary results indicate that a single application failed to control goosegrass at satisfactory levels, regardless of rate and growth rate, < 40% control at five weeks after treatment (WAT). Also, the sequential application did not provide complete goosegrass control by 7 WAT. Finally, sequential application of reduced topramezone rates was more effective than a single application of high rate, 4- and 2- application sequence achieved >60% control 7 WAT.
Stop 3: Strategies for the Postemergence Control of Tropical Signalgrass in Bermudagrass Turf, Katarzyna ‘Kate’ Gawron
Kate Gawron, a biological scientist in Dr. Pawel Petelewicz’s weed science lab, discussed results from a postemergence control of tropical signalgrass trial in bermudagrass turf. See here poster below.
Stop 4: Field Metrics to Promote Plant Health and Performance, John Reilly
John Reilly, the Director of Agronomy for the golf course at the Resort at Longboat Key, made a notable appearance as a guest presenter at this year’s field day. His insightful presentation zeroed in on leveraging field metrics to optimize plant health and performance tailored to golf courses. By employing various equipment, gadgets, and innovative apps, he showcased how precise soil moisture mapping, tracking of clipping yields, and other data-driven approaches can significantly elevate playability and overall turf conditions. In a nutshell, John’s key message was succinctly captured as “Stick a Number to It!”—an approach that can enhance effective communication of course conditions to golfers. John also had a couple of furry companions in attendance who almost stole the show.
Stop 5: Fungicide Efficacy Field Trials for Florida Turfgrass, Dr. Phil Harmon and Alec Dunker
Dr. Harmon, UF/IFAS turfgrass plant pathologist and the director of the Rapid Turfgrass Diagnostics Lab, provided an in-depth discussion on his recent fungicide efficacy trials for controlling pythium root rot. The trial compared four fungicides—Segway, Resilia, Banol, and Subdue—administered through four applications within a 14-21 day period. While all the fungicides effectively controlled the disease, Resilia was the central product of discussion. Resilia, an innovative root health product by Envu, harnesses the power of three active ingredients to combat soilborne pathogens and mitigate nematode populations.
Additionally, Dr. Harmon mentioned that he also has current research trials for management of fairy ring and take-all root rot. These results are not quite conclusive, but hopefully in time to be presented during the Florida Turfgrass Association conference in November.
Alec Dunker, a Doctor of Plant Medicine student and student diagnostician with the Rapid Turfgrass Diagnostics Lab, highlighted aspects of sample submission protocols and outlined the diagnostic results for the year 2023. The lab received a total of 409 samples during this period. Notably, bipolaris leaf spot was the most diagnosed disease in bermudagrass samples, while St. Augustinegrass exhibited prevalent issues with take-all root rot, gray leaf spot, and, to a lesser extent, sugarcane mosaic virus in some areas.
Stop 6: Evaluation of Different Aerification Methods of Bermudagrass Putting Greens, Dr. Marco Schiavon
Aerification and topdressing are vital practices for managing golf greens, preventing organic matter buildup and soil compaction. However, they temporarily disrupt the surface and reduce putting quality during the recovery phase.
Dr. Marco Schiavon, UF/IFAS turfgrass specialist at the Fort Lauderdale Research and Education Center conducted a two-year study using a ‘TifEagle’ hybrid bermudagrass putting green, to investigate various aerification and topdressing methods for their impact on soil properties and turfgrass recovery.
Plots were aerified four times a year (May to Aug.) using different methods: 1/2-inch hollow tines, 1/4-inch hollow needle tines, hollow tines 2X + hollow needle tines 2X, or sand injection. Topdressing options included a 90:10 sand:peat mix or green-dyed sand. Measurements were taken before initial aerification and at 7 and 21 days after. Monthly assessments included saturated hydraulic conductivity (Ksat) and organic matter (OM) content.
Results showed that aerification with hollow tines and hollow tines 2X + hollow needle tines 2X reduced firmness and OM, while enhancing Ksat compared to hollow needle tines and sand injection. Sand injection produced the highest percent green cover, similar to hollow tines and hollow tines 2X + hollow needle tines 2X in OM content. Green-dyed sand exhibited higher percent green cover and DGCI than the 90:10 sand:peat mixture.
In summary, using hollow tines exclusively or alternating them with hollow needle tines is optimal for reducing OM while increasing Ksat in hybrid bermudagrass greens. However, this approach may lead to a slower turfgrass recovery compared to other aerification methods.
Stop 7: New and Upcoming Nematode Management Tools, Dr. Billy Crow
Dr. Crow, UF/IFAS turf nematologist, addressed the significance and current management strategies for the three primary nematodes affecting warm-season turfgrasses on golf courses: sting, root-knot, and lance nematodes. Among these, he says, lance nematodes may not inflict the most immediate damage, but they pose a considerable challenge in terms of management. Golf course superintendents commonly use fluopyram (Indemnify, Bayer), abamectin (Divanem, Syngenta; Todal, Quali-Pro; Nemamectin, RightLine), and 1,3-dichloropropene (Curfew) to manage nematodes of turfgrasses. Since lance nematodes are semi-endoparasitic, living most of their life protected within the roots of plants, they need a systemic product to be effective. Curfew and abamectin products only kill nematodes they come into contact with and the properties of these products limit their effectiveness on lance nematodes. And, lance nematodes are one of the few nematodes that the commonly used product Indemnify will not kill. Therefore lance nematodes have been a challenge to manage and have become an increasing concern for golf course superintendents. But through Dr. Crow’s nematicide research trials program comes good news, fluensulfone (Nimitz, Quali-Pro), a dual contact/systemic product can effectively manage lance nematodes when applied in 4 month applications (80 lbs/acre) and is a new tool for turfgrass nematode management.
Another new product, Resilia, the root health product by Envu, previously mentioned in Dr. Harmon’s fungicide trials presentation, also has nematicideal activity and Dr. Crow especially recommends it for root-knot nematodes. Resilia contains fluopyram, the active ingredient in indemnify, but at a quarter of the concentration, making it ideal for treating root-knot nematodes that primarily inhabit the upper level of the soil profile in turfgrass. The short distance needed for a control product to travel to come in contact with nematodes, allows Resilia to effectively manage root-knot nematodes at the lower dose. On the other hand, for sting nematodes located deeper in the soil profile, Indemnify is the preferred control because the higher concentration of fluopyram allows the product to stay viable for the longer distance and time it needs to travel down deeper in the soil profile to reach sting nematodes.
Stop 8: Seeking a Treatment Rotation to Avoid Pesticide Resistance in Nematodes, Wade Davidson and Erica Guri
Indemnify’s extensive and frequent use in turfgrass nematode management raises concerns about the development of resistance. In fact, recent reports of the product’s diminishing efficacy by golf course superintendents since 2019 has led to research that has implicated resistance as the cause, a first for nematode pests. To mitigate resistance development, it is imperative to employ an integrated approach that includes rotating chemistries, incorporating non-chemical control methods, and implementing appropriate application strategies, ensuring that the highly useful product Indemnify remains an effective tool in turfgrass pest management for the long term.
Elucidating the best nematicide rotation schedule to prevent pesticide resistance is the research focus of two graduate students in Dr. Crow’s lab, Wade Davidson and Erica Guri.
Stop 9: ‘Tif3D’ Ultradwarf Bermudagrass- Selected in Georgia, Tested in Florida, Primed for the Future, Dr. Brian Schwartz
Dr. Brian Schwartz, turfgrass breeder from the University of Georgia (UGA), was one of the special guest speakers for this year’s field day. His field presentation started with a bit of history about the development of bermudagrass for golf greens, starting with Tifgreen. He explained that during the early 1900s, the cool-season turfgrasses used were unsuitable for southern golf courses, and greenskeepers spent most of their efforts trying to keep these grasses alive from drought and disease during the hot, humid summers. So, some southern course greenskeepers started using bermudagrass greens. Because the seed came from common-type bermudagrass, it struggled to survive rigorous mowing and had a highly inconsistent appearance, texture, and playability. However, greenskeepers began to see small, dense turf patches surviving the low, rigorous mowing. Dr. Glen Burton later selected the grasses in these patches in the late 1940s to breed Tifgreen 328. This cultivar was an interspecific hybrid between a common bermudagrass from North Carolina and an African Cynodon trasnvaalensis. This cultivar became very popular with southern greenskeepers as it could withstand intense management during the harsh summers and provided a dense mat to suppress weeds. Today, all the most popular bermudagrass cultivars used on golf greens originated from Tifgreen: Tifdwarf, Champion, MiniVerde, and TifEagle, to name a few.
In 2021, Tif3D was released by Dr. Schwartz out of the UGA turf breeding program. This bermudagrass was selected initially from Tifgreen on the 13th hole at Taylors Creek Golf Course in Fort Stewart, Georgia. It was selected due to its dense, dark green color and ability to grow under heavy shade. This cultivar outperforms other cultivars in Tifton-based trials and shows rapid recovery after intense management. Tif3D has shown it can grow back faster from mechanical injury, drought, and disease. Studies on the establishment, fertilizer usage, sprig rates, cutting-in methods after sprigging, and water usage after sprigging are underway. Stay tuned for more about this exciting new grass, Tif3D.
Stop 10: Postemergence Herbicides for the Control of Spotted Spurge in Bermudagrass Turf
Post-Lunch Education: Bermudagrass Cultivars for Consideration, Jamie Tedder, Mark Kann, and Dr. Brian Schwartz
Jamie Tedder, Vice President of Turf at Bethel Farms, discussed their proprietary grass, Bimini Bermudagrass, first selected from a golf course green in Naples, Florida. It has become one of the most popular golf and sports turf bermudagrasses. Bimini is a fine-textured, hybrid bermudagrass with a striking, dark-green color that forms a dense canopy. Mr. Tedder explained Bimini’s rapidly spreading growth habit and quick recovery from injury make it one of the most durable turfgrasses available. Because Bimini has such a thick root and rhizome density, it will quickly establish a dense root system capable of withstanding stresses such as heat, drought, pests, diseases, and heavy foot traffic. There are currently 1,200 acres of Bimini bermudagrass in production.
Mark Kann, Director of Florida Operations for Sod Solutions, discussed the “new kid on the block,” Celebration Hybrid bermudagrass. This cultivar was developed in the Celebration X Program at Mississippi State University. Mr. Kann explained that this program aims to create new Celebration bermudagrasses with improved cold tolerance, finer texture, fewer seedheads, and less thatch. Celebration Hybrid is just that. It has a dark-green color that responds well to fertilizer and has reduced seed head production. Celebration Hybrid also has aggressive lateral growth, resulting in excellent recovery from traffic and wear damage. The grass also is a superb rooter, producing “carrot roots.” Celebration Hybrid also has excellent regrowth, which makes it a very producer-friendly grass. This is one bermudagrass you want to keep on your radar.
Dr. Brian Schwartz finished the field day off with an additional talk about “Tif” bermudagrass cultivars.