Turfgrass Scouting Report: August 2, 2020
We have officially made it to August!! Historically, people will look back on 2020 as a great year for the game of golf. Every superintendent I’ve spoken too, has had a record breaking year for rounds of golf at the course. Most courses in the area are typically seeing around 250 rounds a day at the weekends. Junior golf is through the roof when compared to recent previous years. So, things for golf are looking good.
Weather
The weather over the last two weeks has been fairly warm, with a few isolated thunderstorms throughout the Chicago district.
Looking ahead the current weather pattern is set to continue, with low’s around the mid 60’s and high’s around the low 80’s. Almost everyday has a low to moderate chance of rainfall.
Sunshine Course Renovations
With the help of Chris Flick from Cogs Hill, we’ve been able to spray off all the areas required in preparation for the renovation work on the Sunshine Course. In the next week or so we’ll be scalping down all the tees and fairways, then aggressively verti-cutting to create a seed bed for the new grasses.
We recently ungraded the irrigation system on the Sunshine Course. Dan Dinelli from North Shore Country Club, graciously donated the Toro irrigation computer. Mike Skopik from Leibold Irrigation, Inc. graciously donated the FIU and Darrick Robbins helped us procure two Lynx Smart Satellite’s at a reduced cost. The CDGA Foundation and Turfgrass Program appreciates all the help and donations, thank you.
Pests
If you have a history of goosegrass problems you’ll definitely be seeing it right now. The above picture was taken this past week up in the Northern suburbs.
Based on the Smith-Kerns model we’re about to see a significant reduction in dollar spot disease pressure at the start of next week.
Recent Turfgrass Research Publications
Author’s and title: Vines, P.L., Hoffmann, F.G., Meyer, F., Allen, T.W., Luo, J., Zhang, N. and Tomaso-Peterson, M., 2020. Magnaporthiopsis cynodontis, a novel turfgrass pathogen with widespread distribution in the United States. Mycologia, 112(1), pp.52–63.
Abstract: “The genus Magnaporthiopsis of Magnaporthaceae (Magnaporthales, Sordariomycetes, Ascomycota) contains species that are predominantly necrotrophic pathogens, often producing simple hyphopodia and dark, ectotrophic runner hyphae on plant roots and stems during colonization. Fungal isolates from turfgrass roots with dark and ectotrophic runner hyphae were examined and identified based on morphological, biological, and phylogenetic analyses. Maximum likelihood and Bayesian methods were implemented to obtain phylogenetic trees for partial sequences of the 18S nuc rDNA, ITS1–5.8S-ITS2 nuc rDNA internal transcribed spacer, and 28S nuc rDNA regions, and of the minichromosome maintenance complex 7 (MCM7), largest subunit of RNA polymerase II (RPB1), and translation elongation factor 1-alpha (TEF1) genes. Our isolates consistently formed a distinct and highly supported clade within Magnaporthiopsis. These findings were reinforced by common and distinctive biological and morphological characters. Additionally, we conducted pathogenicity evaluations and demonstrated the ability of this fungus to colonize roots of ultradwarf bermudagrass, one of its native hosts, via ectotrophic, dark runner hyphae, causing disease symptoms including root discoloration and reduced root and shoot mass. Altogether, our discoveries enabled recognition and description of a new species, Magnaporthiopsis cynodontis, which has widespread distribution in the United States.”
Author’s and title: Hutchens, W.J., Gannon, T.W., Shew, H.D., Ahmed, K.A. and Kerns, J.P., 2020. Soil surfactants influence fungicide movement in United States Golf Association putting green soil. Journal of Environmental Quality, 49(2), pp.450–459.
Abstract: “The management of root and crown diseases of turfgrasses is challenging. To manage these diseases, golf course superintendents and other turfgrass managers often spray fungicides at a high carrier volume and irrigate after application to move fungicides into the root zone. Furthermore, previous research has demonstrated that soil surfactants can increase fungicide movement and distribution in soil. Two laboratory experiments were conducted using lysimeters, which were coated with sand on their inner walls to prevent preferential flow and contained 90/10% sand/peat moss (v/v), to determine the effects of soil surfactants on movement of selected fungicides in soil. The soil surface in the first experiment was treated three times at 2‐wk intervals with one of three soil surfactants: Aquifer (propoxylated polyethylene glycols), Fleet (polyoxyalkylene polymers), and Revolution (modified alkylated polyol). The soil in the second experiment was treated with only Revolution four times at 2‐ to 3‐wk intervals. Immediately after the final surfactant application, soil columns were treated with 14C‐labeled fungicide. 14C‐Myclobutanil was applied in the first experiment, and 14C‐azoxystrobin and 14C‐propiconazole were applied in the second experiment. In the first experiment, 14 percent units more of the recovered 14C‐myclobutanil was detected in the 5‐ to 7.6‐cm sampling depth, and >4 percent units more was detected in the 7.6‐ to 10.2‐cm depth after soil surfactant application compared with the fungicide‐alone treatment. Each soil surfactant also yielded >28% more leachate than the nontreated control. In the second experiment, the total recovered 14C‐azoxystrobin and 14C‐propiconazole in the 7.6‐ to 10.2‐cm depth increased by 2.8 and 1.9 percent units, respectively, compared with soil treated with fungicide alone. These data indicate that soil surfactant inclusion may increase fungicide distribution in soil, which may enhance the efficacy of fungicides in suppressing root and crown diseases.”
Author’s and title: Mattox, C., Kowalewski, A. and McDonald, B., The effects of iron sulfate heptahydrate water carrier volumes on Microdochium patch suppression and turfgrass quality. Agronomy Journal.
Abstract: “Microdochium patch is a turfgrass disease caused by the fungal pathogen Microdochium nivale (Fries) Samuels & I.C. Hallett that occurs most commonly in cool‐humid regions such as the Pacific Northwest. Fungicide applications are the predominant method of controlling this disease, although alternatives to fungicides are desired in areas where pesticide restrictions occur. Previous research has shown that 97.6 kg FeSO4·7H2O ha−1 applied every 2 wk in 814 L ha−1 water carrier suppresses Microdochium patch; however, turfgrass thinning occurred. The objective of this trial was to determine if higher water carrier volumes would mitigate turfgrass thinning while still suppressing Microdochium patch. This field trial quantified the effects of four different water carrier volumes of 97.6 kg FeSO4·7H2O ha−1 applied every 2 wk on the suppression of Microdochium patch, percent green cover, and turfgrass quality of an annual bluegrass putting green in Western Oregon. This research demonstrated that 97.6 kg FeSO4·7H2O ha−1 applied every 2 wk suppressed Microdochium patch on annual bluegrass putting greens to equivalent levels regardless of water carrier volumes ranging from 1019 to 4075 L ha−1. Higher percent green cover was also observed when higher water carrier volumes (3056 or 4075 L ha−1) were used. While iron sulfate heptahydrate treatments suppressed Microdochium patch to less than one percent disease throughout the trial, no water carrier volume reduced annual bluegrass thinning enough to be considered acceptable for golf course putting greens.”
For anyone interested, Dr. Lee Miller’s most recent disease report can be found at https://turfpath.missouri.edu/reports/2020/07_31_20/.
Please don’t hesitate to call or email and I’ll ensure you get a rapid response.
Thanks,
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Bobby Kerr, Ph.D. Senior Director of Turfgrass Programs. Chicago District Golf Association, 11855 Archer Ave, Lemont, IL 60439. C: (312)-519–7940. W: (630)-685–2307.
