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Rank #1: Virginia Turfgrass Council – Update on Annual Bluegrass Weevil Populations in Virginia.
Virginia Turfgrass Journal – Emeline Daly, Graduate student, School of Plant and Environmental Science – Turfgrass Management; Tom Kuhar, Ph.D., Professor, Department of Entomology; David McCall, Ph.D., Assistant Professor, Department of Plant Pathology, Physiology, and Weed Science Annual bluegrass weevil (ABW) (Listronotus maculicollis) is the most damaging insect pest of golf course turfgrass in the northeastern United States (McGraw and Koppenhöfer 2007). The pest was discovered in New England in 1931, but until recent years, was largely confined to the northeastern states and not considered to be an issue in Virginia. That situation has changed drastically. ABW Biology and Damage While this weevil prefers to feed and lay eggs on annual bluegrass (Poa annua L.), it can also survive on creeping bentgrass (Agrostis stolonifera L.) if necessary. Annual bluegrass weevil is particularly damaging to short mowed areas of golf courses including tees, fairways, collars, and greens (McGraw and Koppenhöfer 2007). Overwintering adult weevils (Fig. 1) will emerge in early spring and crawl to shortly-mowed grass and begin laying eggs that will hatch into larvae (Fig. 2) that feed on roots and root crowns. There are likely multiple generations of this weevil in Virginia based on multiple peaks of adult activity observed in 2019 from three Virginia golf courses based on weekly soap drenches on untreated turf plots (Fig. 3). Our data indicated three distinct peaks in ABW adults for each location. Because ABW can quickly cycle through their generations and continue to oviposit for a long time, often, multiple life stages are present at any given time once summer arrives. As a result, there is a difficulty with correct and effective application timing for management of ABW. Distribution of ABW in Virginia It is believed that ABW has been in Virginia since at least the mid-2000s, but the overall establishment and damage caused by this pest across Virginia golf courses has not been completely studied. Based on a survey by McGraw and Koppenhöfer (2017) of golf course superintendents in the northeastern states, several from Virginia reported ABW to be present on their golf courses. Thus, in 2019, we attempted to contact 203 golf course superintendents in Virginia with regards to whether they had a confirmed case of ABW at their golf course. Based on 49 responses, 36 golf courses (73.5%) responded with confirmed cases of ABW (Fig. 4), leaving 12 courses unaffected. Eleven of the 12 courses that reported not having ABW also have bermudagrass fairways, however 10 of the 12 courses have cool-season putting greens. There was only one course that reported no ABW and had an all cool-season turfgrass course. Although annual bluegrass suffers the most damage from ABW, we have observed that creeping bentgrass is also damaged. Creeping bentgrass is a popular cool-season turfgrass that is widely used for golf course putting greens across America, as it can be mowed at significantly shorter heights. In Virginia, however, creeping bentgrass is used for more than just putting greens, and many courses use it for fairways, collars, and tee boxes as well. Because of Virginia’s transition zone climate and creeping bentgrass being a cool-season grass, keeping creeping bentgrass healthy throughout the summer is challenging enough without ABW threatening it. This summer specifically, Virginia golf courses were affected with damage primarily showing on fairways, tee boxes, and collars. Insecticides and ABW Effective control of ABW is a major challenge. Different insecticides are typically used to target adults and larvae. With regards to larvicides, some preventive larval control of ABW can be achieved with standard neonicotinoids or chlorantraniliprole (Acelepryn®) typically applied for white grubs. However, research has shown that these standard soil turf insecticides only provide about 50% control of ABW larval populations (McGraw and Koppenhöfer 2017). The aforementioned survey also reported that the most effective larvicides for ABW include: Ference, Provaunt, Matchpoint, and Dursban. Insecticides most commonly used for ABW adults include pyrethroids such as deltamethrin (Deltagard®), bifenthrin (Talstar®), cyfluthrin (Tempo®), and lambda-cyhalothrin (Scimitar®, Battle®). The organophosphate chlorpyrifos (Dursban) also provides great control of adult ABW. Repeated and frequent use of pyrethroids on golf courses in the northeast has led to pyrethroid resistance development in populations of ABW. Because we do not know where our ABW populations on Virginia golf courses came from, it is possible that pyrethoid resistance genes may be present in our ABW populations already. Thus, monitoring for pyrethroid resistance will be a focus of research at Virginia Tech for the coming years. In 2019, we collected several populations of ABW adults from Virginia golf courses and tested them for pyrethroid susceptibility using a filter paper dip bioassay. With this bioassay, a typical spray tank concentration of bifenthrin was applied to filter paper discs and compared with water dipped control paper placed in Petri dishes. Weevil adults were placed in the dishes and were maintained on the treated filter paper. This assay should result in near-complete mortality of weevils in 24 hours as pyrethroids have rapid activity on insects leading to quick death. Based on ABW populations collected from Harrisonburg, Stanardsville, Nokesville, Crozet, Roanoke, and Blacksburg, mortality ranged from 32.5% to 100% with a lot of variation. This is an indication that our Virginia ABW populations may likely have different levels of pyrethroid resistance in them. This is indeed something that should be closely monitored. Pyrethroids are still a good option for adult control, especially given their cheap cost, but rotation of insecticide classes is strongly recommended as a resistance management tool. We plan to closely and more thoroughly examine this topic in the future in Virginia. Please contact us if you have a high population of ABW and you are interested in screening them for susceptibility to insecticides. The post Virginia Turfgrass Council – Update on Annual Bluegrass Weevil Populations in Virginia appeared first on The Turf Zone.
Rank #2: Tennessee Turfgrass Association – TifTuf at the Swamp: Laying the Foundation for Excellence.
Tennessee Turfgrass – Julie Holt, Content Director, TheTurfZone.com The Swamp. Just the name evokes a visceral reaction from every college football fan in the south. Florida Gators beam with pride at the mention of their legendary stadium. Other SEC teams’ fans may respond with less enthusiasm, but no one can question the fact that Steve Spurrier-Florida Field is an iconic place to play college football. The statistics don’t lie – three national titles, eight conference titles, three Heisman trophies and many winning seasons attest to the Florida Gators’ dominant football program. And for every football team that plays on such a big stage, there’s always an unsung hero, a hero that endures the elements and injury, is pushed to its limits, yet expected to perform week after week, year after year – the turf. Most fans never give it a second thought. Even players and coaches seldom notice this integral part of the game unless it isn’t performing. But turfgrass managers recognize the field as the very foundation of a top-tier NCAA football program. It is this recognition of the importance of playing surface that drives sports turf managers across the country and beyond to seek the most functional and attractive turfgrass available for their sports fields. A Surprising Find In November of 2018, when Jason Smith, Director of Sports Turf at University of Florida, saw the events calendar for Spring of 2019 at Ben Hill Griffin Stadium (aka The Swamp), he knew it was time to start planning a field renovation. To accommodate a concert and graduation, flooring would be covering the turf for nearly a month beginning in April. With field renovation on such a large scale looming, he began his research. After researching and narrowing the field to three varieties that might uphold the standard expected of a high-level SEC stadium, Smith made a visit to the university turfgrass program’s research site. Dr. Jason Kruse, University of Florida Assistant Professor and Turfgrass Specialist, showed Smith research plots. Nematodes are a major challenge for turfgrass managers in Florida, so when Smith saw that TifTuf had such a low incidence of nematode growth, his interest was piqued. “The one that really caught my eye was the nematode resistance plot that I saw. It looked like nematodes hadn’t even touched it,” said Smith. “It looked like a control plot. That’s what really caught my attention.” Upon learning of other features of TifTuf –staying green later in the season than other Bermuda grasses, excellent wear tolerance, increased drought tolerance – Smith was certain he’d found the right fit. The Road to Excellence It is easy to recognize what makes a turfgrass variety a great choice for certain uses, but we rarely get a peek into how that specific variety came to be. As new cultivars are introduced with increasing regularity, it is important to understand what goes into the making of that brand, especially when the stakes are this high. TifTuf’s recent explosion onto the warm-season turfgrass scene is unprecedented, and while it may seem like an overnight sensation, many years of evaluation and development went into establishing this variety as a top performer. Developed by the experts in Tifton, Georgia, TifTuf was 20-plus years in the making. “It’s important that we studied this in Georgia, but we had bigger plans for TifTuf,” says Dr. Brian Schwartz, associate professor at the University of Georgia and TifTuf breeder (alongside Dr. Wayne Hanna). “It’s very important to do a lot of testing to make sure you don’t release a product that gets out to the public and fails.” After a painstaking breeding and development process, it was clear that this turf would be a great success if it was brought to market properly. Enter The Turfgrass Group, a licensing and marketing company made up of turf professionals. The team at The Turfgrass Group recognized TifTuf as the superior product it is and began implementing their unique strategy to ensure that this variety would provide the exceptional performance it had shown in trials. For the high quality that is demanded at The Swamp, it is essential that the variety chosen perform consistently and predictably under intensive management strategies. That’s where single-sourcing and meticulous crop inspection come in. With its initial release, all TifTuf plant material was sent directly from Georgia Foundation fields to licensed and Certified sod farms, ensuring unprecedented consistency in sod production. A second source was later added in California, a first for any UGA variety. This source continues to follow the rigorous standard set in the eastern U.S., while allowing wider-spread distribution in the western part of the country. Every one of the 60 U.S. sod farms and 42 Australian farms that produce TifTuf get it from one of those two sources, guaranteeing purity in over 6,000 acres of TifTuf grown in the U.S., plus hundreds more in Australia. Prior to planting, a state inspector sees every field and must approve it before TifTuf is planted. The history of the field is reviewed, and if it meets standards, approval to plant is granted. But this is just the beginning of the quality assurance process. Once planted and growing, every square foot is visually inspected by The Turfgrass Group three times per year. “With our continuous inspection of TifTuf, we’re ensuring genetic purity,” says Bill Carraway, VP of Sales and Marketing at The Turfgrass Group. “We’re going to spot anything that’s not TifTuf, but our focus is on off-type Bermuda grasses. At times, it’s like looking for a needle in a stack of needles.” It is this rigorous process that has led TifTuf to success never before seen. It has been licensed to more farms in less time than any licensed proprietary cultivar in history, and in its first three years in the marketplace has earned recognition in two sports field of the year awards. Technical Expertise and Superior Product Choosing the right turf is only the first step of many in field renovation. After the sod was removed at The Swamp, material had to be removed to correct the field profile and drainage and to create the best possible foundation for the Gators’ new field. Smith hired Laser Turf to complete the field construction and worked with Pike Creek Turf Farm to get the sod. The looming deadline for having a usable field was the annual youth football camp hosted at The Swamp in late July. Smith and the Laser Turf team worked quickly to ensure the field was bulldozed, leveled, and sodded in plenty of time for rooting to begin and for the field to be ready for action ahead of the 2019 football schedule. Smith has been quite pleased with the performance of the new field. After hosting four home games in five weeks, recovery was excellent and Smith did not plan to rye overseed at the end of the season. “TifTuf has helped with the stadium because of the way that it’s holding up,” says Smith. “After the game, repair is minimal compared to what we were doing. I wanted something that, when you got into the fourth quarter, it didn’t even look like you’d played four quarters.” Smith continued, “I’m just super excited to have this much Bermuda grass this late as a base going into the off season. Where we’re going to be at next season – I’m very excited.” The Gators have confirmed their status as a leader in the fiercely competitive SEC, and every element of the team’s performance is under close scrutiny for the top caliber performance that is expected at this level. While the collective efforts of over 80,000 fans may be called the 12th man on game day, a solid foundation of an exceptional playing surface may just be the ultimate champion. The post Tennessee Turfgrass Association – TifTuf at the Swamp: Laying the Foundation for Excellence appeared first on The Turf Zone.
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