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Tag: brown patch

2015 Fungicide Resource

(Megan Kennelly, KSU Plant Pathology)

Hello everyone,

The 2015 edition of Chemical Control of Turfgrass Diseases is available at the following website:

 

http://www2.ca.uky.edu/agc/pubs/ppa/ppa1/ppa1.pdf

 

This guide from University of Kentucky (Paul Vincelli and Gregg Munshaw) is updated every year with new products and all the latest research findings. Bookmark it, print it, use it, love it.

Kentucky-turf-fungicides-2015-ppa1_Page_01

 

Heavy dollar spot pressure

This week is pretty hot, but overall its been pretty mild this summer. Dollar spot is most active at temps ranging from 59-86 and we’ve had a lot of temps in that range. We’ve also had some dewy mornings. Dollar spot often is at its most active stage here in Kansas during late August into September, with long, cool, dewy nights.  Make sure you stay on your game with your dollar spot management program. There are lots of tips and tricks in the dollar spot section of this guide:

http://www2.ca.uky.edu/agc/pubs/ppa/ppa1/ppa1.pdf

Here are some symptoms out at Rocky Ford:

The heat this week will increase brown patch pressure. I saw some of that today, too, but it was kind of faint and didn’t show up well in the pictures. But, it is definitely there, and lurking…. On the brown patch front, we will probably move permanently out of brown patch weather pretty soon and hopefully won’t have to worry about it any more until 2015.

Is this brown patch?

(Megan Kennelly, KSU Plant Pathology)

Whew, it’s hot out there. We are coming up on August which is usually the peak stress time for our cool-season turfgrasses. Tall fescue lawns can start tanking this time of year, and I get a lot of samples, emails, and phone calls about brown patch.

Is this brown patch in tall fescue? What do you think? How would you figure it out?

 

So – how can you tell if it is brown patch or something else? In tall fescue, brown patch makes pretty characteristic lesions. Look for this in the areas showing decline. You might have an easier time looking on the edge of the patches instead of in the middle. Look for tan spots with a dark halo. Here are a bunch of examples: (you can click to zoom in a little bit.)

In that first stand of turf above, it was NOT brown patch.

When thinking about environmental stress there are a lot of things to consider – water (too much, too little), drainage, fertilizer, thatch, mowing practices…Take a look at this stand of turf right here:

Compaction or fill issues: This site (above) had a lot of construction activity a year or 2 ago. Construction can mean compaction from heavy equipment, backfill with less-than-optimal (to put it diplomatically) soil, and other problems. Those factors reduce root health, and then areas with reduced root function are the first to crash out when summer stress arrives.

Poor root health – I have a low area in my yard (with heavy clay soils) where water pools during heavy rains. We haven’t had heavy rains for quite awhile, but the root systems there probably didn’t grow as well. Now, those spots are showing decline while surrounding areas are looking much better.

Thatch – As one final possibility, don’t forget about thatch. Now, tall tescue is a bunch grass (lacking laterally-spreading rhizomes and stolons) but it can still build up thatch. Plus, sometimes tall fescue is planted in a blend with Kenctucky bluegrass which is more prone to thatch.

I talked about thatch not too long ago on the Facebook page. Here is some information about thatch (click the link to view).

Thatch-info

So, don’t assume you’ve got brown patch. There are plenty of other problems (even more than I listed here) that affect the health of tall fescue in summertime.