Annual bluegrass (ABG) (Poa annua L.) is a prolific seed producer in the spring on golf courses that in turn decreases aesthetic quality and trueness of ball roll on coolseason putting greens. Proxy (ethephon) applied twice in the spring after green-up is the current industry standard after the loss of Embark (mefluidide) from the turf and ornamental market. However, plant growth regulators including Proxy have been used for years to help suppress ABG seedheads with inconsistent success. The primary objective of this study was to determine if ABG seedhead suppression is improved by adding a late fall application of Proxy to the two traditional spring applications of plant growth regulators at nine locations with diverse environments. A second objective was to determine the importance of including Primo Maxx (trinexapac-ethyl) in fall and spring applications. Adding a late fall application of Proxy prior to the two spring applications (F+S+S) improved control of ABG seedheads over the traditional two spring applications (S+S), but the magnitude of improvement varied among locations. Abbreviations: ABG, annual bluegrass; AUSCPC, area under seedhead cover progress curve; CBG, creeping bentgrass; DAISA, days after initial spring application; F+S+S, Proxy + Primo Maxx applied once in fall plus twice in spring; GDD, growing degree day; S+S, Proxy + Primo Maxx applied twice in spring. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.

Dollar spot (DS) (Sclerotinia homoeocarpa F.T. Bennett) is an important disease on golf course turfgrasses in the United States. The objective of this study was to elucidate disease reduction mechanisms related to lightweight rolling. Creeping bentgrass (Agrostis stolonifera L.) plots that were subjected to daily (5 d wk−1) rolling treatments (1x a.m., 1x p.m., 2x a.m.) showed significant DS reductions when compared with a nonrolled control. Treatments rolled in the afternoon (after dew and guttation fluid dissipated) exhibited similar area under disease progress curve (AUDPC) values as treatments rolled in the morning in 2008, 2009, and 2010. Both 1x rolling treatments resulted in significant DS reductions compared with the control in 2009 and 2010. The 2x d−1 treatment exhibited significantly less DS than the control in all years as well as significantly lower AUDPC values than both 1x rolling treatments in 2009 and 2010. Rolling 2x d−1 improved turfgrass quality compared with all other treatments in each year of the study. All rolling treatments exhibited higher root zone volumetric water content (%VWC) compared with the control in 2010, and significant effects on %VWC were observed on individual dates among treatments. Results indicate previously unidentified effects of rolling on putting greens, including added physical and biological effects, which may be contributing to DS suppression.

The Stimpmeter and Pelzmeter are two devices commonly used to measure putting green speed. The Stimpmeter was released in 1978 and the Pelzmeter followed approximately 25 years later. The Pelzmeter uses various technologies to potentially reduce measurement variability. However, it is unclear how similar these meters compare for measuring putting green speed. The objective of this research was to compare the measurement variability between the two devices when measuring putting green speed and to determine if they give similar results on the same putting surface. This study was conducted at four sites: the University of Arkansas (Fayetteville, AR); the University of Tennessee (Knoxville, TN); the University of Connecticut (Storrs, CT); and Michigan State University (East Lansing, MI). At each site, three evaluators used each device to measure putting green speed on plots with varying green speeds. There was a strong linear, one‐to‐one relationship between the Pelzmeter and the Stimpmeter when measuring putting green speed on the same turf. Measurement repeatability (as measured by standard deviation) among different evaluators was improved with the Pelzmeter at one of the four sites. There were no differences in measurement repeatability between the devices when a single evaluator repeatedly measured the same turf with the same device.

Results suggest that sand topdressing was more consistent at reducing dollar spot (Clarireedia jacksonii) in fairway turfgrass more so than rolling. This practice could be an effective cost-saving alternative to reduce frequent fungicide applications. Research was conducted from 2011 to 2014 on a simulated golf fairway and examined dollar spot severity responses in a mixed-stand of creeping bentgrass (Agrostis stolonifera) and annual bluegrass (Poa annua ssp. reptans) to sand topdressing and rolling. Treatments consisted of biweekly sand topdressing, rolling at three frequencies (one, three, or five times weekly), a control, and three replications. Infection was visually estimated. Sand topdressing significantly (P < 0.05) reduced disease up to 50% at the peak of the dollar spot activity in 2011, 2013, and 2014. Results on the effects of rolling on dollar spot were inconsistent.

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