IF YOU haven't done so already, this weekend or early next week is a great time to protect your plants against brown patch and Pythium blight. Environmental conditions next week will be ripe for these two diseases. Moreover, anthracnose, dollar spot, summer patch and leaf spot could also flare up depending on where you are with fungicide applications. I mention leaf spot because we have been dealing with a Bipolaris leaf spot in the Midwest for two or three years that does not respond well to applications of iprodione. This disease also remains active throughout the summer months and has been problematic primarily for older golf courses. The disease tends to be more severe on certain clones of older creeping bentgrass fairways causing a "splotchy" reddish appearance to fairways. It does not manifest into distinct symptom. An image of typical stand symptoms is below.
Last year we initiated a fungicide trial at a course in Wisconsin to investigate chemical control options and found that Heritage TL, Insignia and a tank mixture of Chipco 26GT and Daconil Ultrex suppressed symptoms when compared to the non-treated control. Chipco 26GT by itself did not suppress the symptoms, indicating that Daconil Ultrex was more effective in controlling this disease. Note that I use the word suppress we have not been able to prevent the development of this disease, only suppress the symptoms. Here is the report from last year's trial. This has been a difficult disease to work with because it only seems to affect certain clones. Thus it took some time to figure out how to rate it.
Some other things to consider for next week: limit mowing by alternating mowing and rolling, skip clean-up passes, raise the mowing height and absolutely avoid applications of DMI fungicides to putting greens.
2 Responses to “Heat Wave Forecasted for Next Week”
Thank you Jim for the heads up. It is invaluable to us (me).
We have some Dollar Spot but it's not out of control and it's about time to do another application. We will heed the NO DMI warning.
The 5 day of 70% humidity average readings has been constant for 33 days and we've had 15 to 24 Hours a day of temp/hum at 150+ very often. This seems to be a bad year for potential Dollar Spot.
Thanks again Jim. I will gladly send you the Excel spread sheet I've built to track the 5 day average and the 150 index if you're interested.
Tom
Hi Jim,
Thanks for the headsup and suggestions to get to the other side of this weather. We heed your warning and we will see how well we can handle a week of Mid-Atlantic weather here in the upper Mid-west.
Post a Comment