Turfgrass Scouting Report: July 28, 2019
Well, my favorite band is no longer “Wet, Wet, Wet”. It’s now the “Red Hot Chili Peppers”. We have another 34 days to grind out till the end of August, keep it positive out there, this, too, shall pass!! Over the last two weeks we’ve seen several things, Japanese beetle activity, Take-All patch, bacterial etiolation, leaf spot, and some physiological stress responses of Poa annua.
Here at the Sunshine Course the maximum temperatures have been fluctuating between ~75–95°F, while the minimum temperatures have been fluctuating between ~55–75°F over the last 2 weeks. Soil temperatures have been fluctuating between ~55–75°F for the past two weeks. We had a couple of rain days at the start of last week, but nothing to bad. Towards the end of last week we had significant rainfall, seeing 2 inches in one day.
Last week Ron and I had the pleasure of attending the UW Madison Turfgrass Field Day. It was a great day with lots of up to date research being carried out.
There has been significant adult Japanese beetle activity with multiple sites in several states. Below are images of active adults and Japanese beetles at various stages in the life cycle.
Several courses are experiencing Take-All patch. In the image below you’ll see the ectotrophic runner hyphae colonizing the roots. At this point there is really nothing we can apply for Take-All, your best bet is to reduce stress as much as possible. The timing of spring applications based on soil temperature are critical for the control of Take-All patch. I think the cool start to this season has resulted in the outbreaks we are seeing now.
In the previous scouting report (July 14) I discuss bacterial etiolation, please refer to scouting report for more information. The application of PGR’s are known to be associated with the development of this phenomenon. In the previous scouting report I discuss and highlight the recent research results in relation to bacterial etiolation.
Bipolaris leaf spot is active in the area, we’ve had several courses call regarding this issue. Below are images of the lesions caused by bipolaris and the bipolaris spores under a microscope.
There has also been calls regarding physiological decline of Poa annua. The root system of the Poa annua on these courses has significantly reduced over the last few weeks. My thinking is the damage was done during the hot spell we recently had, and the Poa annua is simply struggling now. One thing you should always keep in mind regarding Poa annua, is it’s genetic make up is to grow, produce seed and dry. It has evolved for millions of years doing just that, and it’s one of the most widespread grass species in the world. It does not want to stick around for a long period, so any stress we put on Poa annua is really pushing it to the edge.
For anyone interested Dr. Lee Miller’s most recent disease report can be found at https://turfpath.missouri.edu/reports/2019/07_25_19/.
Please don’t hesitate to call or email and I will ensure you get a rapid response.
Subscribe to scouting reports: http://cdgaturf.org/
Bobby Kerr, Ph.D. Director of Turfgrass Programs. Chicago District Golf Association, 11855 Archer Ave, Lemont, IL 60439. C: (312)-519–7940. W: (630)-685–2307.
Ron Townsend, MS. Manager of Turfgrass Research. Chicago District Golf Association, 11855 Archer Ave, Lemont, IL 60439. W: (630) 685–2310.