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K-State Turfgrass

Month: July 2016

Sad, soggy roots and some Pythium root rot in turf

(Megan Kennelly, KSU Plant Pathology)

 

“We got six inches of rain, and the golfers are saying, ‘Hey, isn’t it great for the turf that we are getting all this rain?’ Hah – Not exactly!”

That was part of a recent conversation with a superintendent in south central Kansas. Yes, moisture is good, but not 6 inches all at once! It seems that this year the water is either OFF or ON. When it is OFF it is really OFF. When it is ON, it is coming down in buckets. I guess nobody gets exactly what they want when they need it.

We continue to see poor rootzones on all kinds of plants, from trees to turf to tomatoes to petunias. Putting greens are really suffering. I’m seeing lots of brown, mushy roots with tissue sloughing off.  Poa annua is also checking out in the heat, big time.

Below are some pics of roots. These are some older pics I have posted before, but they look just like most of the roots I’ve been looking at for the past couple of weeks. In some cases Pythium root rot is occurring as well, but in many cases the turf seems to be declining all on its own. For example, I had some samples where multiple plugs were submitted from multiple greens. All the roots were in poor health, but I found Pythium (at a low level) in just a few of them.

Root images:

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What to do?

Check out the post today from Dr. Fry with some tips about managing bentgrass to prevent summer decline. Click HERE.

Another great set of tips is outlined HERE, starting on page 6, from U of Kentucky.

For Pythium root rot, here is an excellent site from NCSU, where Dr. Jim Kerns has conducted research on this disease.

http://www.turffiles.ncsu.edu/diseases/pythium-root-rot

In current research, Dr. Kerns reported in a Tweet that he also saw good results with Signature Xtra watered in (click HERE).

To date, we have not had a different disease, Pythium root dysfunction, occur in Kansas. At least, I have not seen it any any samples run through KSU. I did just learn from our neighbor Dr. Lee Miller at U. of Missouri that they picked up that disease in St. Louis. Lee mentions it in his update HERE if you want to learn a little more about it.

 

Traffic and compaction

(Megan Kennelly, KSU Plant Pathology)

When droughty, wilting turf  is subject to traffic from vehicles, mowers, or even feet, it can develop tracks. If possible, when turf is wilty, avoid traffic altogether. If you must apply traffic, try to do it during cooler parts of the day. Sites with underlying problems like compaction are more prone to drought and therefore more sensitive to traffic.

The KSU Turf Team has several projects related to drought, management, and traffic. Want to learn more? Come out to the Turf Field Day! In addition, stay tuned to this blog for future research updates with specific results from our trials.

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We continue to see samples coming into the diagnostic lab with poor root health, but no pathogens. We got a ton of rain in May, and those root systems declined from too much water. Now that we are into the summer heat, the plants can’t thrive on those compromised root systems. Take note of problem areas, and over time you can try to alleviate compaction, change traffic flows, reduce drainage issues, etc. As much as possible, make the site function at its best to support the plants. You don’t want the site to make things more challenging than it needs to be.