Turfgrass Scouting Report: June 7, 2020

The floods of 2008

Memorial day weekend and the month of May have passed, I’m sure for many reasons it’ll be one to remember; from COVID-19 to record rainfall to record high temperatures.

Weather

It’s hard to believe that the all time record for rainfall in the month of May was broke on May 19, 2020. That’s right a total of 8.49 inches had fallen before the end of the month, incredible.

So, by the end of May the total rainfall for the month was 9.51 inches. In the Chicago area the average temperatures were only slightly above normal. However, on June 2, the record high temperature of 94 degrees was recorded at O’Hare International Airport.

Weather modelling

It looks like the warm start to June is set to continue with several days above normal in the first week and a half of the month, followed by a slight cooling for 4 days.

Weather forecast

Diseases

Smith-Kerns model and dollar spot activity

Increased dollar spot activity has been noted in the last week or so. Based on the Smith-Kerns model and the weather forecast, disease pressure looks to be fluctuating between moderate and high risk.

Red thread (Laetisaria fuciformis)

Red thread activity has been noted in rough areas. When I was learning greenkeeping in the 90’s, red thread was always described as a symptom of low nitrogen. However, the current thinking is it is more associated with damp, cool growing conditions.

Weeds

Clover

Broadleaf weeds continue to be active, most likely in areas where voids exist.

Insects

Ant mound

I saw this active ant mound on a putting green nursery last week.

Cottonwood seeds

Cottonwood seeds. Photo courtesy of J. Schaefer

An issue that occurs every year at the start of June is cottonwood seeds. A few years back, J. Schaefer sent a picture of his method for the removal of cottonwood seeds from the fairways. It basically involves attaching a roller to the back of a ProGator, and rolling fairways in the morning when dew is present.

Recent turfgrass publications

Fine fescues continue to be a topic of interest for superintendents in the Midwest. So, I thought I’d share a recent publication from researchers at Purdue University, University of Minnesota, University of Wisconsin — Madison, Oregon State University, Rutgers University and DLF Pickseed USA. The manuscript is a comprehensive review of the history, production, establishment, management, use, and availability of fine fescues. If you have fine fescue areas or are considering them on your course, I highly recommend reading this article. I have included the authors, title and abstract below. The manuscript is open access and can be found here.

Braun, R.C., Patton, A.J., Watkins, E., Koch, P.L., Anderson, N.P., Bonos, S.A. and Brilman, L.A., 2020. Fine fescues: A review of the species, their improvement, production, establishment, and management. Crop Science.

Abstract: “Fine fescues (Festuca L. spp.) comprise a group of five cool‐season grasses used in turfgrass systems under many conditions: strong creeping red fescue (F . rubra L. ssp. rubra Gaudin), slender creeping red fescue [F . rubra L. ssp. littoralis (G. Mey.) Auquier], Chewings fescue [F . rubra L. ssp. commutata Gaudin; syn. F . rubra L. ssp. fallax (Thuill.) Nyman], hard fescue (F . brevipila Tracey), and sheep fescue [F . ovina L.; syn. F . ovina L. ssp. hirtula (Hack. ex Travis) M.J. Wilk.]. Their extensive geographic distribution is a result of adaptation to many different environmental and management conditions especially low‐input sites. This review summarizes the history, production, establishment, management, use, and availability of fine fescues; discusses strengths and shortcomings of fine fescue; identifies knowledge gaps; and provides an outlook toward further research on this group of grasses. Improved cultivars have been developed in recent years that expand the geographic distribution and uses of species but additional efforts to increase seed yield and improve abiotic and biotic stress tolerances are still needed. Expanded use of fine fescue could be achieved through increased sod production of fine fescue, though current research‐based information is limited. Research on fine fescue allelopathy and the contributions of fungal endophytes, both of which could lead to reduced pesticide requirements is important for improved pest management. Future research on fine fescues should focus on implementation and management of new cultivars that possess enhanced abiotic and biotic stress tolerance that will result in fewer inputs and improve the appeal and adoption of these low‐input grasses.”

Dollar Spot

Kabbage, M., Piotrowski, J.S., Thill, E., Westrick, N.M., Ralph, J., Hockemeyer, K. and Koch, P.L., 2020. Poacic acid suppresses dollar spot and snow mould in amenity turfgrass. Plant Pathology, 69(1), pp.112–119.

Abstract: “Plant‐based antifungal agents offer an alternative to synthetic fungicides in amenity turfgrass disease management. Poacic acid is a by‐product of the biofuel production process that has exhibited antifungal activity, and the objective of this research was to determine its ability to serve as an effective management tool for economically important turfgrass diseases such as dollar spot and snow moulds. In vitro and field tests were conducted in Wisconsin and Michigan, USA from 2015 to 2017 to determine the efficacy of poacic acid in suppressing the economically important turfgrass pathogens Clarireedia jacksonii and Microdochium nivale . Poacic acid demonstrated strong antifungal activity against both pathogens in vitro , inhibiting growth of C. jacksonii and M. nivale by 93% and 74% relative to nonamended media, respectively. Poacic acid reduced dollar spot in the field in one of two years, but failed to suppress snow mould when applied alone. Poacic acid was an effective mix partner for snow mould control when combined with a synthetic fungicide, an important attribute because no single fungicide currently on the market provides acceptable snow mould control under heavy disease pressure. Future research should focus on improving poacic acid field efficacy so that it can be incorporated into plant‐based disease management strategies for amenity turfgrass.”

Acknowledgements

We’d like to thank PBI-Gordon Corporation, Syngenta, BASF and Bayer for the donation of plant protection products for the maintenance of the Sunshine Course.

In an on going basis, JW Turf in partnership with John Deere Golf have agreed to support the Sunshine Course by providing machinery for maintenance.

Thanks,

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Twitter: CDGATurfgrassProgram

Bobby Kerr, Ph.D. Senior Director of Turfgrass Programs. Chicago District Golf Association, 11855 Archer Ave, Lemont, IL 60439. (630)-685–2307.

Dedicated researchers and turf pathologists working for golf course superintendents in the Chicago area.