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Category: Diseases

Large patch activity in research plots

Cool, wet weather has triggered large patch activity in golf courses – and in our research plots.

The photos below are from an ongoing research trial. You can read some details about the study in our online research update from spring. PhD student Mingying Xiang is the lead researcher on this study, under the mentorship of Megan Kennelly and Jack Fry.

The photos below show different zoysiagrass breeding lines. For each plot, one side was inoculated in Sept 2016, and the other side is protected with fungicides to allow ongoing rating of quality and agronomic traits in the absence of disease AND to serve as a “healthy check.”

As you glance through the photos, you can clearly see the large patch on the inoculated sides of many of the plots, while the fungicide-treated side is clean. However, you will also see plots where you can’t even tell which side is which. That is, even the inoculated, non-fungicide-treated side is looking clean. We are hoping those  may be resistant lines to examine in further testing. Stay tuned! Turfgrass breeding takes a long time!

Last hiccups of summer diseases

Early last week we saw a couple last gasps of the summer diseases, with some Pythium on a tall fescue lawn:

It was greasy, it was mushy, and after “a night in the box” there was classic Pythium mycelium. Foliar Pythium is rare on tall fescue lawns, usually coming in during very wet weather on sites that have received a little too much water and perhaps a little too much N. When this one came in, it was after one last blast of some heat, but with cool, cool temps on the horizon. Now that we are coming into this nice, consistent cool weather it’s really too late to consider fungicides, and instead we can concentrate on fall renovations AND tweaking cultural practices to help reduce disease risk next year. There was also a last hiccup of brown patch from a golf course fairway. Same story – with lows in the low 60s and even 50s, those diseases should stay quiet and hopefully we won’t see them until 2018.

Next door in Missouri, Dr. Miller is reporting some continued sightings of Pythium root rot (which is different from foliar Pythium) and basal anthracnose. I would agree we are not out of the woods yet. You can see his photos HERE.

Start thinking about large patch applications now if you aren’t already

Photo – large patch symptoms in spring

We humans are enjoying the cool weather, and our cool-season grasses are too. However we are coming up on the time when our warm-season grasses start to shut down, and the season when the large patch pathogen likes to infect our zoysia. Sometimes we see symptoms in fall if conditions are very cool and wet. I have not seen any around here yet, but in Missouri some is firing. Our main time of seeing the symptoms is spring.

In Kansas, applications in September have been quite effective in reducing symptoms through most or all of the following spring. With this early cool weather, leaning towards earlier rather than later in the month may be wise. Next door in Missouri they’ve seen good results with EARLY spring applications as well – read about it HERE in Dr. Miller’s excellent post about application timing.  In Kansas, when we’ve tried mid/late spring applications when symptoms are already pretty apparent, they don’t work well, if at all. For details on the newest products you can check the large patch section here (click to page 18)

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

 

Here is a video with some descriptions of the biology and symptoms:

 

Grey Leaf Spot – All the way from 2015.

(By Jared Hoyle, KSU Turfgrass Research and Extension)

Someone told me and I am not sure if it is correct or not, “that grey leaf spot will infect crabgrass before it hits our desirable turfgrass species”.  The other day I saw some grey leaf spot crabgrass in a ryegrass lawn and got me thinking that this is about the time grey leaf spot starts to kick in around here.  I went back through the blogs and back in 2015 (Actually August 25, 2015) I posted about grey leaf spot.

I wanted to pass along the blog again for everyone that may have had grey leaf spot in the past.

http://blogs.k-state.edu/turf/grey-leaf-spot/

Also check on  more control options for grey leaf spot in this publication – http://www2.ca.uky.edu/agc/pubs/ppa/ppa1/ppa1.pdf

***Mention of trade names or commercial products in this article is solely for identification purposes and does not imply recommendation or endorsement, nor is criticism implied of similar products not mentioned by Kansas State University.***

Don’t forget to follow me on twitter @KSUTurf.

Also, visit our facebook page www.facebook.com/KSUTurf

The 2017 Turfgrass Research Reports Now Online!

(By Jared Hoyle, KSU Turfgrass Research and Extension)

The 2017 Turfgrass Research Reports are now available!!!! See what research projects the KSU Turfgrass Team have been up to.

Click the link below to take you to the Kansas Agriculture Experiment Station Research Report Page.

http://newprairiepress.org/kaesrr/vol3/iss4/

Volume 3, Issue 4 (2017) Turfgrass Research

Research Reports

PDF

Measurement of Evapotranspiration in Turfgrass: Recommended Techniques and Adjustment Coefficients
Kenton W. Peterson, D. Bremer, Kira B. Shonkwiler, and J. M. Ham

PDF

Evaluating Zoysiagrass-Tall Fescue Mixtures in Kansas
Mingying Xiang, J. Fry, and M. Kennelly

PDF

2012 National Turfgrass Evaluation Program Tall Fescue Test: 2016 Data
L. Parsons, Michael J. Shelton, M. Kennelly, J. Griffin, and J. Hoyle

PDF

2013 National Turfgrass Evaluation Program Bermudagrass Test: 2016 Data
L. Parsons, Michael J. Shelton, J. Griffin, and J. Hoyle

Always remember to READ THE LABEL for the correct rate, turfgrass tolerance, and specific instructions before application!!!

***Mention of trade names or commercial products in this article is solely for identification purposes and does not imply recommendation or endorsement, nor is criticism implied of similar products not mentioned by Kansas State University.***

Don’t forget to follow me on twitter @KSUTurf.

Also, visit our facebook page www.facebook.com/KSUTurf

Anthracnose crown rot in putting green turf

We recently received a sample with anthracnose crown rot. Anthracnose can be tricky to diagnose from a distance or a drive-by. The symptoms can look like other diseases or stresses such as physiological root decline. Another tricky thing is that those same stresses can make the turf more prone to anthracnose. Yikes! It’s worth investing in a high-quality hand-lens, and with a good hand lens and a steady-hand you can often see the anthracnose structures lurking down at the base of plants. Sending to the lab as a follow-up is another good step, since we can look for other pathogens that might be lurking in the roots.

The photo below is through a dissecting microscope, but those same dark spines can often be seen with a hand lens. Look for structures on green tissue, not brown/dry tissue. Anthracnose is pretty good at colonizing stuff that is already dead, as an opportunist. When we see it on juicy green tissue that is when the disease is active.

 

For more on anthracnose, including several photos you can check this page:

http://www.bookstore.ksre.ksu.edu/pubs/EP147.pdf

Here is an excellent list of best management practices:

http://turf.rutgers.edu/research/bmpsanthracnose2015.pdf

Last but not least, anthracnose is one of the many diseases covered here:

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

Many of the practices to reduce anthracnose also promote overall turf health. That is, when you implement agronomic practices to promote good rooting you also reduce the risk of anthracnose and other problems. You may not be able to do ALL of the beneficial agronomic practices you would like, due to budgetary limits or lack of equipment or golfers’/greens committee opinions, but the more you can fit in, the better.

New Turfgrass Publications

(By Jared Hoyle, KSU Turfgrass Research and Extension)

The KSU Turfgrass Team has been busy updating turfgrass extension publications.  Some of the most recent publications include benefits of a healthy turf, lawn fertilization guide and turfgrass mowing.

Enjoy the updated publications!

Benefits of Heathy Turfgrass

Environmental, economic, health, and safety benefits of turfgrass found in lawns, athletic fields, parks, and roadsides.

https://www.bookstore.ksre.ksu.edu/Item.aspx?catId=545&pubId=12800

Lawn Fertilizing Guide

This guide helps homeowners determine how much fertilizer to apply to keep lawn vigorous and healthy.

https://www.bookstore.ksre.ksu.edu/Item.aspx?catId=545&pubId=10639

Turfgrass Mowing: Professional Series

Mowing basics for professional turfgrass managers. Information on mowing height and frequency, clippings, mowing pattern, mower operation, blade sharpening, mower selection, maintenance, and safety

https://www.bookstore.ksre.ksu.edu/Item.aspx?catId=545&pubId=712

Mowing Your Lawn

Mowing basics for homeowners. Includes information on mowing height and frequency, pattern, mower operation, maintenance, and safety.

https://www.bookstore.ksre.ksu.edu/Item.aspx?catId=545&pubId=615

Recycling Grass Clippings

Information for homeowners on why and how to recycle grass clippings.

https://www.bookstore.ksre.ksu.edu/Item.aspx?catId=545&pubId=701

 

For more turfgrass publications visit the KSRE Bookstore.

https://www.bookstore.ksre.ksu.edu/Category.aspx?id=528&catId=545&Page=1

Help us help you – Submitting a sample to the KSU Plant Disease Diagnostic Lab

You think you have a plant problem, and you want some help. So, now what? You’ve heard of the diagnostic lab, but you aren’t sure what to do.

Here are some tips on submitting a turf sample

Here are some tips on submitting a tree/shrub sample

Two nice-sized turf plugs, at the transition of healthy and damaged? YES! That is great:

Tiny branch, smaller than my pinky? NOT! This is not ideal:

So, check out those links above for the guidelines on what to send.

If you have more questions feel free to email me at kennelly@ksu.edu

Wet and humid = slime mold weather

Hey, what’s that stuff? Slime molds! They can look pretty alarming, and they can pop up seemingly overnight. They are pretty harmless, and you can read more HERE and if you would like a fascinating glimpse into how these organisms work there is a short video clip HERE called “Are you smarter than a slime mold?”

 

Some other shapes and colors of slime mold:

 

Brown Patch Resources

(By Jared Hoyle, KSU Turfgrass Research and Extension)

Tall fescue [Festuca arundinacea Schreb.] is one of the most predominantly used cool-season turfgrass species in the transition zone. Its deep root system and coarse textured leafs lend to its ability to withstand drought, heat, and wear stress. Although it is well adapted to survive the summer months in Kansas, it can be susceptible to injury from disease. Brown patch [Rhizoctonia solani] is a disease that can damage leaf tissue, shoots, and the crown of tall fescue during the summer months. This disease is most prevalent during periods of high humidity, high temperature (above 80°F), and high nitrogen levels. During the mornings mycelia can be seen forming a “smoke ring” around the affected area. Applications of preventative fungicides have proven to be a successful management strategy in reducing the occurrence of brown patch incidences in tall fescue stands.

Here are some resources from the past about brown patch!

Last year Dr. Fry was seeing brown patch in May.  With moisture and warm nights brown patch can start to develop.  http://blogs.k-state.edu/turf/im-not-ready-to-be-thinking-about-brown-patch-jack/

There are many products out there for brown patch control in turfgrass.  Which one is right for you.  Here is a quick update on research that was conducted at Olathe on some brown patch products. http://blogs.k-state.edu/turf/best-way-to-get-your-turf-noticed-brown-patch/ 

Do you know what brown patch looks like?  Do you know how to tell the difference between turfgrass stress and the disease.  Dr. Kennelly can show you the difference. http://blogs.k-state.edu/turf/is-this-brown-patch/

K-State Publications

Commercial Management of Brown Patch – https://www.bookstore.ksre.ksu.edu/pubs/EP146.pdf

Homeowner Management of Brown Patch – http://www.plantpath.k-state.edu/extension/documents/turf/Brown%20patch%20%20homeowners%202016.pdf