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Update (5/9/2013)

Ducks, Dandelions, & Pythium

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Cold, roller coaster weather pattern for April and early May.

To say this spring is a roller coaster ride doesn’t do it justice.  It may be more akin to the “Tower of Terror” type plunge (click here to see the ride) that keeps occurring over and over again.  April temperatures ended at -1.5 degrees F below normal, but there were a lot of birdies and bogeys to get to that score.  Early May has thus far replicated April’s mood swings, particularly on May 3rd, which had the lowest daily high temperature ever recorded in a May. This went along with the first recorded May snowfall in Kansas City since 1907. I’ll discuss a bit more about precipitation below, but suffice it to say we are well above normal for 2013. Does anyone remember 2012?

Along with the saturated soils, the low soil temperatures (see below) have made it a particularly bad year for spring seeding.  Two-inch average daily soil temperatures dropped into the 40’s for most of Missouri last week, which shocked potentially germinating seeds into growth submission.  This is not good news for those with lawns or other areas trying to recover from last year’s drought damage.  Soil temperatures have not allowed proper seed germination, and the young seedlings that may be germinating now don’t stand a real chance when the heat (in theory) hits soon.  The forecast looks to stay mild over the next 5 days, but 2-3 week old seedlings going into June are not in a promising situation. 

Low Missouri soil temps for this time of year

Quick Hits

Large patch symptoms occurring throughout Missouri
  • Large patch reports have come flooding in from KC, STL, and Columbia over the last three days.  If you have symptoms, it is important that with the continued wet and mild conditions that a curative fungicide application is made to prevent further spread.  Also, map areas where the outbreaks are now, and specifically target them with preventive fall applications in late August/September. 
Dandelions and other broadleaves are infesting lawns at unseen levels in 2013
  • All of this precipitation and cool temperatures have been good for a few things, including ducks and dandelions.  In talking with colleagues, along with chickweed, we have never seen an infestation and bloom of dandelions like this year.  This is certainlya combination of last year’s drought damage opening up the canopy, tall fescue’s bunch type growth habit not allowing it to fill the gaps, and a feeble spring seed germination period.  So what to do?  Certainly not a weed-n-feed product during this early May time frame.  Most of these products contain 0.8 – 1.0 lbs N/1000 sq ft, which will increase leaf growth to the detriment of a final push of root growth before summer hits.  Plus, this will be a perfect setup for brown patch on tall fescue lawns when the heat does eventually come to join the conducive soggy conditions.  Go for a broadleaf herbicide on its own, (homeowners have hose spray nozzle options), and skip the fertilizer.  Besides, do you want to mow every 3 days instead of 5-7 now?
Pythium root rot could be active now.
  • What disease would love this current 5.26” above normal precipitation more than a water mold?  Well nothing…  Golf superintendents should be aware that Pythium root-infectors may be actively infecting roots now, and preventive fungicide applications should be considered.  It is a misconception to think that Pythium only likes it hot.  This may be true for Pythium blight (which is rarely seen on mature creeping bentgrass stands) but is not true for Pythium root rotters.  Remember when applying fungicides to susceptible areas that the fungicide needs to be watered-in, preferably with  1/8– 1/4” of irrigation.  If you’ve had a confirmed or even suspected case of Pythium root dysfunction (which I’m not aware of yet in Missouri), a)  contact me and b) you will need to apply Insignia as a start to your preventive program.  See this previous update for more information.  Also, the East Coast is also considering this same warning - (click here to see blog post from NC State). 

2013 Field Day, July 30th - Save the Date

Field day talks include info on wetting agents, lawn care, tree health, and turfgrass diseases.

Yes, plans are already underway for the 2013 University of Missouri Turf & Ornamental Field Day.  The event will be held on Tuesday, July 30th at the Research Farm.  We have several informative talks lined up (see above) as well as three afternoon off-farm tours at the University of Missouri Botanical Gardens, the newly renovated Mizzou Athletic Fields, and the newly renovated Columbia Country Club.  Registration and event details will be coming soon. 

Have a good weekend. 

Lee Miller
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Extension Turfgrass Pathologist
University of Missouri