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K-State Turf and Landscape Blog

Author: kennelly

Anthracnose crown rot in putting green turf

Posted on by kennelly

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.

Human health – not just plant health! Stay hydrated out there and avoid heat stress.

Posted on by kennelly

On this blog we are usually talking about plant health, but here’s a quick switch to human health. We want all of our Kansas green industry folks to stay healthy and safe in the summer heat.

You already know this, but sometimes it is worth reminding ourselves that heat stress and dehydration can be very serious. A friend-of-a-friend of mine got very dehydrated once on a camping adventure, and she was very sick for several days (dizzy, vomiting).

This link has some common-sense tips:

http://online.ksre.ksu.edu/tuesday/announcement.php?id=35357

Take extra care of new crew members who are not used to the heat. For one thing, those folks are less used to it. Second, a new crew member may feel the need to just buck up and take it and be afraid to speak up that they need some shade or a water break. So keep an eye on everyone, but especially those that may be more vulnerable.

Take Advantage of Breaks in Summer Heat for Putting Green Management

Posted on by kennelly

By Jack Fry

Looks like we’ve got a short-term period of cooler temperatures over the next several days.  Midsummer heat relief is good for us, and it’s also a great time to do some of the cultural practices we often avoid during midsummer heat.

Creeping bentgrass and annual bluegrass don’t like the heat, and really don’t appreciate it when we implement certain cultural practices during hot weather.  On greens that have shallow roots and experience indirect heat stress, any kind of stress brought about with cultural practices can sometimes be the “straw that breaks the camel’s back.”  Consider implementing some of the following during short stretches of cool weather:

1) Solid tine aerification.  Opening up the surface of the green can help get oxygen to roots and prevent a “sealing off” of the surface that can arise when organic matter accumulates.

2) Verticutting.  Using vertical knives to cut leaves and stolons is certainly a stress to the plant, and now is a good time to do it if your greens are grainy (a la Johnny Miller!), or are accumulating more organic matter at the surface than desired.

3) Sand topdressing.  Topdressing during midsummer can be stressful to the plant especially if it the sand is dragged into the surface.

4) Product applications.  Some products can potentially cause more injury to creeping bentgrass and annual bluegrass when applied during hot weather, including liquid fertilizers, plant growth regulators, wetting agents, and even some fungicides.   Labels on some products specify temperatures in which they should be applied.  Use the break in the temperatures to apply products that may be needed.

5) Mowing and rolling.  If you haven’t done it yet, raise the mowing height if you can, and roll a few days each week instead of mowing.  Having more leaf area is always a good thing for the plant.

Summer tree reminders – watering, scorch, and leaf loss

Posted on by kennelly

Looking for some tips on watering trees? You can learn some suggestions here:

http://kansashealthyyards.org/component/allvideoshare/video/water-wise-way-to-irrigate-trees?Itemid=101

And, what’s the deal with trees losing leaves in summer? You can read about how and why trees shed leaves in summer in this article (just scroll past the tomato article to find it). Here is the link:

http://hnr.k-state.edu/extension/info-center/newsletters/2017/June20_2017_25.pdf

Scholarship and Research Tournament – Thank you!

Posted on by kennelly

Thank you to everyone who participated in or sponsored the KGCSA Scholarship & Research Golf Tournament! The event was Monday at Colbert Hills. Thank you to Matt Gourlay and his team for hosting – we know it is a lot of work!

The full list of sponsors can be found on the Kansas Golf Course Superintendents Association page. If you are not a KGCSA member you can explore the webpage and learn more about the organization, and perhaps you will decide to become a member, too.

Thank you so much!

Thanks to everyone who played on a team, donated funds or auction items, sponsored a hole, or bid on an auction item. The KSU Turf Team appreciates your efforts. Thank you to Christy Dipman for organizing the event. Thanks to L.C. Lacy for serving as our auctioneer – that was amazing!

 

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

Posted on by kennelly

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

“Soil Evolution Par for the Golf Course”

Posted on by kennelly

Soil water management is a big topic on this blog. Are you curious about some of the science behind it?

How does water infiltration rate change as putting greens age? Big hint – it sure does not get BETTER over time.

This topic was featured in the recent edition of the news magazine of the CSA News (from the American Society of Agronomy/Crop Science Society of America/Soil Science Society of America). Here is the link to the article.

The article also talks about a weird iron layer that can build up over time.

Here is a key figure from the article, sourced from the USGA. Read the whole article to get the story. As you can see, older greens = slower infiltration:

Beware localized dry spot in putting greens – exacerbated by hot, dry winds

Posted on by kennelly

Summer is really here now, with fireflies, trips to the swimming pool, and … hot south winds to suck the moisture out of the ground. In sand-based putting greens, localized dry spot can pop up FAST, causing major damage in a short period of time.

Here is what localized dry spot can look like:

Keep an eye on your soil profile so you can stop this damage before it starts. When you get damage to the extent shown in those two photos above it is a long road to recovery.

To check for localized dry spot, pull up some cores and use the “droplet test” by putting drops of water on the plug. If the drops just sit there, not wicking in, you have a problem. The soil is water-repellent.

Sometimes there is a defined hydrophobic layer with normal soil above and/or below, so check at different depths, all the way down the rootzone:

You might also notice water beading up on the surface and not wicking in.

You don’t want this to sneak up on you. Keep an eye on your soil profile, especially locations with a history of problems. Aerification and use of wetting agents can help get moisture where it needs to go.

This example below shows how a slight change in the rootzone can cause problems. The round spots are all locations where the soil was altered for research, with little mini-plots inside tubes sunk into the ground. These spots are prone to LDS. We all know that putting greens are pretty sensitive, so be careful if you are changing up your sand topdressing or other soil-related factors.