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Another stressful week


As Brandon cleverly noticed and wrote in the comments, I too am wondering about Dr. Kerns's 'evening' nip of whiskey at 8:11 am (?). Too many turf plugs must driving Jim a little batty. I'm not far behind!

I could probably just cut and paste my information from the past 2 weeks, since it's been more of the same. Hot, humid, stress.

One superintendent told me he had recorded a 2-inch soil temp of 98 degrees. That is pretty smokin' hot. Another mentioned receiving "another unwelcome" 1-inch of rain, with more in the forecast.

On the pathogen side, brown patch, dollar spot, Pythium foliar blight, fairy ring, and the crown rot/basal rot phase of anthracnose have all been active. I even had a sample of Pythium foliar blight from a putting green which is pretty rare here. It’s more common in fairway height turf, or in the collar. But, this plug was crawling with mycelium.

John posted some great info from the GCSAA. If you missed it, be sure to scroll down and give it a read. As noted, communication is pretty key right now, and this may give you some ammo to help discuss things with golfers who might think that "more water" is going to solve all your problems!

On the plus side, we have two brand new Turf Doctors here at K-State. Two grad students, Jason Lewis and David Okeyo recently (one was today!) defended their PhD's in the Hort Department. Congratulations, guys!

Now... gotta get back to those sample plugs in the lab :)

Another Successful Field Day and Poa annua takes a dump!

Welcome back Lane!

It seems like the entire US is struggling with heat, rain and dead grass. I left for Scotland on July 14th and the sample total in the TDL was fairly normal. The week I was gone we received over 50 samples. WHOOPS! Anyway it seems like Poa annua just crapped the bed because of the relentless rainfall followed by intense heat (at least intense for us). So I agree with Brandon and Lane's equation of No Wind + Heat + Rain=Dead Grass-especially Poa annua. The roots of affected plants are short, black and pitiful looking. We have had golf course superintendents reporting soil temperatures in excess of 95 F within the top 2 inches. When this occurs there is really nothing that can be done to save Poa annua!

If you are losing grass please consult John's post earlier this week. He posted a lot of nice cultural practices that will help. Like raising the mowing height, alternate between mowing and rolling and carefully monitor soil moisture levels. However the most important point, is constant communication with the members, golf pro, general manager, owner, etc. Get them prepared for a loss in density and losing Poa annua. I know it sounds negative, but that is really the best thing to do. Especially since we have not had a hard summer in the Midwest for 3 years.

As far as diseases, we are seeing just about everything. This is sick for me to say, but this summer has been a pathologist's dream. We have diagnosed brown patch on creeping bentgrass, fine fescue and tall fescue. We have seen oodles of fairy ring through the Midwest and summer patch has just begun to show its ugly head. This has been another reason Poa annua is struggling so much in the Midwest. We have even seen a few cases of Pythium blight. We have not seen a lot of anthracnose however. The difference between this year and last year has essentially been temperature. Last July our average high temperature was 72, yet this year we are hovering closer to 82. When I was at NC State I helped Lane teach a turfgrass pathology class in the two year program and he always strongly emphasized to the students that the most important thing to a fungus is water. We had that last year, but temperatures were not conducive for growth. This year has been a different story. We have not been as hot during the day as North Carolina, Tennessee, Kansas, or even Pennsylvania, but our nighttime temperatures have consistently remained above 68 degrees. This is good weather for fungi and bad for turfgrass growth.

Yesterday we had the 28th annual Wisconsin Turfgrass Field Day at the OJ Noer Center. It was a fantastic day with great attendance. The topics ranged from Alternative grasses as a pest management strategy to Hydroseeding with Tenacity. We were really happy to have so many attendees considering the recent weather!

Now it is time to have a wee dram of whiskey to conclude my evening.

Heat + Rain = Dead Grass

First, let me welcome Lane back;
I hope your sabbatical was productive and recharged your batteries! Second, I would also suggest a corollary to the equation, No Wind + Heat = Dead Grass, and that is: Heat + Rain = Dead Grass.

Another area where stress begins to rear its ugly head is in the area of water management- too much, and not enough.
All too often, we see situations where relative humidity is high, and "hand watering" is done to "cool the plants off". Unfortunately, when RH is high, very little of the water
you put down will evaporate, and this creates the potential for several bad things to happen. As Lane described in his post, fans are incredibly important especially in the Southeast because of the need to reduce the local relative humidity so that the plants can manage the heat.
Fungicide programs are also showing excellent differences, and you can tell the difference between those that perform and those that miss a key disease this year.

To give you an idea of just how we are doing this year, a superintendent in TN sent the following out to his colleagues, and I thought it was interesting:

"Over the weekend I had some fun with numbers. I pulled all my weather records for my course for the past 17 years. I counted the number of 90 degree or above days in the months of June , July and August. Pretty interesting. In 2004 we only had 5 days at or above 90 the whole year. 2006, 2007 we had 40 and 47 days respectively. The highest we had ever had in June was 13 in 1996. The highest ever in July was 28 in 1993. The highest ever in August was 29 in 2007.
1993 must have been a rough year because we has 54 days total, but we were closed, rebuilding our greens that year so it didn't hurt me any.

On average we have had 6.8 days in June at or above 90, 11 days in July and 11.5 days in August.

This year we had 18 days at or above 90 in June and we have already had 18 days in July with a week to go.

The numbers are probably a little different in other areas, but by my measure, that had to be the most stressful June for at least the last 17 years and with the exception of 1993, it looks to be the most stressful July. By far the most stressful two month stretch during that time.
Pass this along to others if you think it will make them feel better. Or just remind them that we are all in the same boat, and that football season is getting closer every day."

It seems to me that golf provides an adequate analogy for taking care of turf under this kind of stress. We have all heard some version of the saying, "The person that misses it the best will win", and I think an appropriate version of that for a summer like this is, "The superintendent who knows how to lose a little turf will carry the day". Like he said, "football season is getting closer every day". Try to stay cool everyone!


I'm back.

For those of you who were hoping that my first post would be on bacterial wilt, I am sorry to disappoint you, but we have more important problems here in the Southeast right now.

Several years ago, I got a call from an angry homeowner who lived in a golf course community. The golf course superintendent had installed a fan adjacent to the green in her back yard. Said fan was preventing her from enjoying her patio, keeping her awake at night, and reducing the value of her property.

She must have been a scientist of some sort, because she asked me if I had a mathematical model that could be used to determine if a fan was necessary. So I broke out my plant physiology, meteorology, and calculus books and after several weeks of analysis, I came up with the following equation:


I don't think she liked that answer because I never heard from her again. But this summer is proving my equation to be correct: I have never seen fans make such a huge difference in the survival of creeping bentgrass putting greens as they are this year. Just about everywhere I've visited, the creeping bentgrass being impacted by fans is relatively healthy, whereas the turf furthest away from the fans or on greens without fans is really struggling.

It's been a difficult summer and there's no sign of it getting any easier. But if one positive thing can come out of it, we can use it to demonstrate the benefit of turf fans, fine tune the placement of existing fans, or fight for the money to install additional fans. Don't miss this opportunity!

On the disease side, a number of superintendents in our area are still struggling with Pythium root rot, and some summer patch is also showing up on creeping bentgrass greens. For more information about these diseases, please see the following post from last year.

We have also seen a couple of cases of Rhizoctonia zeae on creeping bentgrass greens. This pathogen induces similar symptoms to brown patch, but is active at higher temperatures and the patches or rings have more of an orange coloration. Most fungicides labeled for brown patch will provide good control of R. zeae, but this pathogen is not sensitive to thiophanate-methyl and is less sensitive to iprodione so you should avoid these products.

Heat wreaking havoc on golf courses nationwide

A message from Clark Throssell and the GCSAA!

Prolonged periods of high temperatures, and in some cases, excessive rainfall, and high humidity have made life uncomfortable for golfers and golf courses alike, with Mother Nature holding all the cards for true relief.

"The simple fact is the cool-season turfgrasses such as bentgrass, fescue, bluegrass, annual bluegrass (Poa annua) and others are stressed when temperatures climb and humidity is high," Clark Throssell, Ph.D., director of research for the Golf Course Superintendents Association of America, said. "Golf courses in many parts of the country experience this every year, however what makes the situation so dire this year are the high levels of extended heat and humidity, and the sizeable part of the country affected (Midwest, Mideast, Northeast and Mid-Atlantic)."

According to Throssell, golf facilities and those entrusted with managing the golf course – golf course superintendents – are not alone in this battle with the elements. However, the nature of their product makes their challenge greater.

"We are certainly seeing homeowners, athletic fields and businesses suffer turfgrass damage brought on by the conditions," Throssell said. "What makes it more difficult for golf facilities are the mowing heights are much lower and traffic is much heavier. That just adds to the stress on the turfgrass."

Throssell indicates that golf course superintendents are addressing the issue with a variety of management practices to make sure turfgrass survives. While there may be some short-term impact on playability of the course, the alternative is the loss of grass, the closure of the course and the additional costs of re-establishing playing surfaces (primarily putting greens).

He also cautioned golfers from thinking that water, whether from rain or irrigation, is the answer to the ills. There is a difference between heat stress and drought stress. Adequate irrigation will alleviate drought stress. Adequate irrigation will not alleviate heat stress. It is not only possible, but likely, for a turfgrass plant to be adequately watered and still suffer from heat stress under extended periods of high temperatures.

Among the practices that superintendents are implementing to manage golf courses include:

•Raising the mowing heights of playing areas, most notably putting greens.
•Alternating daily practices of mowing and rolling putting greens, with consideration to skipping a day if the schedule of play allows.
•Forgoing double mowing, topdressing, verticutting or grooming greens.
•Watering to provide adequate soil moisture, but not over watering as saturated soil will cause the turfgrass to decline rapidly.
•Hand watering as much as feasible. If a green has a dry spot or two, superintendents will hand water the dry spots only and will not water the entire green. When the entire green shows stress from a lack of water, superintendents use the overhead sprinklers and water the entire green.
•Avoid aerifying using large diameter tines that penetrate deeply into soil and remove a core of soil. If a superintendent feels the putting surface is sealed, venting using small diameter solid tines or other similar technique is employed.
•If fertilizer is required, small amounts of fertilizer are applied via a sprayer and observation of the response occurs before fertilizing again.
•Monitoring and adjusting golf car traffic patterns to minimize stress to turf.

Throssell indicated that during periods such as this, it becomes easy to compare golf course conditions and pressure decision makers into actions that might prove detrimental to the long term health of the playing surface.
"Communication is vital," Throssell said. "Superintendents, golf professionals, owners, managers and others must be in constant contact with golfers to educate them on what is happening at the facility. But golfers must also understand that golf courses are like snowflakes – no two are alike. Some courses may be able to withstand the challenges of Mother Nature better than others because of better drainage and soil conditions, better air flow due to the placement of trees, less traffic or the presence of greater financial resources.
"We know the weather conditions will become more agreeable. What is important right now is to manage the golf course in a manner so that turf can be kept alive until that point."
GCSAA is a leading golf organization and has as its focus golf course management. Since 1926, GCSAA has been the top professional association for the men and women who manage golf courses in the United States and worldwide. From its headquarters in Lawrence, Kan., the association provides education, information and representation to more than 20,000 members in more than 72 countries. GCSAA's mission is to serve its members, advance their profession and enhance the enjoyment, growth and vitality of the game of golf. The association's philanthropic organization, The Environmental Institute for Golf, works to strengthen the compatibility of golf with the natural environment through research grants, support for education programs and outreach efforts. Visit GCSAA at

For more information contact:
Clark Throssell, Ph.D., GCSAA director of research, 800-472-7878

Relentless heat and humidity


I have a pile of turf and ornamental samples to get back to in the lab, so this will be quick.

Basically, heat and humidity continue to pound us. From what I've read, cool-season root growth pretty much ceases when 4-inch soil temps are >77. Our average here in Manhattan over the past 10 days is 84, with some spikes up into the 90's. So, we are hurtin'.

I know that some superintendents are feeling stress almost as much as, or worse than, the turf itself. Golfers, boards, and greens committees aren't always in tune with what Mother Nature is throwing at us. I was happy to hear that a few supers are using this national blog, and some of my K-State stuff that I send out here at home, to help explain things to their boards, etc.

Fairy ring is burning in some sites:

Brown patch is active in many sites, including in some fairway height Kentucky bluegrass at our research facility. That was a first for me. I snapped a photo but it did not turn out so great.

For any of you interested in the ornamentals side of things, I have a posting about crown rot of hosta and other bedding plants HERE

It's an interesting disease. The pathogen is very closely related to the one that causes southern blight in turf.

Summer Stress Programs for Desert Bentgrass in CA

Developing a Summer Stress Fungicide Program for Coachella Bentgrass (and the Case of the Mysterious #13)

This is a follow up on something I been meaning to address but spurred on by an email I received this week:

Dr. Wong,

I am a Golf Course Superintendent in the Palm Springs area and manage Penncross putting greens. As we both know, heat and cool-season grasses don’t work well together.

Currently we are experiencing exceptional summer bentgrass decline due to high heat and humidity. Are there any fungicide trials or protocols that other Superintendents may be using to minimize effects of SBD? We have fans on each greens, and water as needed with syringing during the day. Our heights are .150 and mowed every other day. Other than that we try to keep them alive.

Hot in Coachella

Yes, bentgrass and triple digit temperatures through the summer get along as well as Meg Whitman and Jerry Brown in California. Based on work done at NC State by Turfgrass Specialist Art Bruneau, cool season turfgrass growth pretty much declines rapidly when 4-inch deep soil temperatures reach 70°F with root and shoot growth completely shutting down at 77ºF and 90ºF, respectively.

With soil temps in the California desert hitting 70 to 90ºF from April to September, it means a long late spring through the fall of tough conditions for superintendents in the desert (including other areas in the SW like Arizona, New Mexico and Nevada) who have to hold onto their bentgrass year round.

Although fighting Mother Nature through this period can be partially successful using fans and syringing; in any case, simply put the high temperatures will result in poor growth and recovery from the bentgrass magnifying any damage caused to the turf by mechanical, environmental or pest stress.

From a pathologist’s point of view, the diseases that would likely cause the most damage to bentgrass in this climate would be takeall patch, Pythium blight , Curvularia blight and algae.


Avg. Hi

Avg. Low

Avg. Prec.




1.27 in.




1.15 in.




0.63 in.




0.08 in.




0.06 in.




0.05 in.




0.19 in.




0.40 in.




0.39 in.




0.11 in.




0.29 in.




0.61 in.

Take all typically infects and damages plants in cool wet weather through the fall and winter. Symptoms can often show up under periods of heat stress because plants with damaged roots simply can’t efficiently use water to keep themselves alive. In the desert, the high temps really hamper the ability of the turfgrass to recover and regrow, magnifying take all damage on bentgrass greens. I won’t cover it much here, but soil pH and manganese management coupled with preventive fall fungicide applications work best for preventing problems with take all.

Pythium blight is a real threat to cool season turfgrass when night time temperatures stay above 68ºF and there’s adequate moisture to trigger fungal growth and spread. There’s an excellent review of Pythium here at the Rutgers website:

Believe it or not, but Curvularia blight is pretty common to find on bentgrass coming from the desert. Curvularia can often be considered a wimpy disease that only attacks weakened or nearly dead bentgrass, but like anthracnoseon Poa, it can be the nail that closes the coffin on your summer stressed bentgrass if not controlled.

Alage can also turn up commonly as it’s quick to colonize wet surfaces and thinned out bentgrass in the summer.

The Mysterious Program #13

As detailed in the Pythium presentation above, Bruce Martin at Clemson is credited with developing a fungicide spray program (#13) that has worked very well for managing diseases on creeping bentgrass in the southeastern U.S.:

The question posed by several Coachella Valley superintendents has been “how well does #13 work in California?”

Well, Bruce’s #13 provides broad spectrum protection vs. a number of summer diseases while using some of Bayer’s “Stress Gard” pigmented materials, and Insignia which BASF is reporting to promote plant health. But….the southeast gets a lot more humidity and #13 is also designed to pick up brown patch and dollar spot; it’s just too dry in Coachella to have these figure as major players in a summer disease profile.

Looking at #13, applications start in late May in the southeast and go at 14-day intervals; here’s the break down with likely targets of activity.

May 22: Tartan 2.0 fl oz --> brown patch/dollar spot control

June 5: Insignia 0.9 oz --> broad spectrum disease control

June 19: Spectro 90 5.76 oz --> broad spectrum disease control (no Pythium actvity)

July 3: Signature 4.0 oz + Daconil Ultrex 3.2 oz --> Pythium control, algae control, stress reduction

July 17: Insignia 0.9 oz --> broad spectrum disease control

July 31: Signature 4.0 oz + Daconil Ultrex 3.2 oz --> Pythium control, algae control, stress reduction

August 14: Chipco 26GT 4.0 fl oz --> brown patch/dollar spot/Curvularia control

August 28: Tartan 2.0 fl oz --> brown patch/dollar spot control

OK – if you discount the presence of dollar spot and brown patch in Coachella, you can see some of these applications would not be necessarily applicable. Also with regard to Tartan which is a mix of Compass and Bayleton, applying a DMI (Bayleton) isn’t necessary, especially if dollar spot pressure is absent. Spectro probably isn’t needed as much, again due to the lack of dollar spot and brown patch pressure.

Pythium pressure is likely to come from June through September with high night time temperatures. Insignia and Signature + Daconil applications would probably give some significant benefits during this time for both Pythium and “plant health benefits”. Although other Pythium-specific fungicides like Subdue, Banol and Stellar could be used, I would save these for overseeding type situations or when you know that hot wet weather is coming. Otherwise, it may be fine to rely on preventive applications of Signature or other phosphonate/phosphite type products during the summer. Although many of the phosphonate or phosphite type products do a very good job of controlling pythium and improving plant health, the “Stress Gard” pigment in Signature is something I think works pretty well as an added layer of stress relief for your turf.

I’d see Curvularia as a constant threat through the season, but it may not be worth using a 26GT application specifically for this disease, when you can get control with other materials.

A contact fungicide like mancozeb (Fore) may work just fine in Coachella for keeping pathogens like Curvularia at bay, plus beating back algae.

So…in putting all of this together, I’d say that #13 is a great program, but not necessarily well fit for southwestern desert bentgrass greens.

Looking at the situation, maybe something like this would work:

May 15: Fore 8 oz

Jun 1: Insignia 0.9 oz

Jun 15: Fore 8 oz

Jul 1: Signature 4.0 oz + Daconil Ultrex 3.2 oz

Jul 15: Insignia 0.9 oz

Aug 1: Signature 4.0 oz + Daconil Ultrex 3.2 oz

Aug 15: Fore 8 oz

Sep 1: Signature 4.0 oz + Daconil Ultrex 3.2 oz

Sep 15: Fore 8 oz

Keeping the Signature and Daconil in the mix as a stress & algae application; Insignia as a 28-day preventive early in the summer and regular applications of Fore to clean up algae and clean up “junk” diseases like Curvularia may work just fine.

I’d like to see some research in Coachella to support the suggestions, but this type of program may be a good starting point. If you think "there goes Dr. Wong, smoking the crack again." - that's fine too; I think it's good to have some discussion about what is working for guys in the desert who are growing bentgrass.

Bottom line: programs like #13, are very good, but may not cover the diseases & stresses unique to the southwest – think about what you’re trying to fight and design a program around that.

A Few Thoughts about Nematodes

One thing that needs some attention as far as bentgrass greens in Coachella is the presence of some new root knot nemtaodes found affecting cool season turf. Very high populations were associated with severe damage at a few locations in Coachella in 2009. As discussed above, the summer stress for growing creeping bentgrass in Coachella is already pretty high – nematode populations really need to be considered in this equation.

This is a green from 2009 in Coachella that took some severe nematode damage; don't let this be you!

If you’re growing bentgrass in the Valley; it’d be worth having a test done to see if you need to worry abouyt these critters as well.

OK – until next week – signing off from the Right Coast…..

Just a brief update

It has been tough to give an update since things have been so busy, but I thought that I would at least give a summary of what I have been seeing in the Northeast either while I was in the field or in the lab.

Typical diseases:
Dollar spot, anthracnose, brown patch and Pythium blight have been working on turf for a few weeks.  Gray leaf spot has also been reported by some in the region, although I am not sure if this has been confirmed by any diagnostic lab.  Also, many courses have been either excessively wet or more likely excessively dry.  The dry conditions have been particularly noticeable around the NJ/NY region.  At this point, it is just about keeping things alive and getting through the summer until conditions change to favor turf growth.

All the talk:
For the last few weeks there have been two unusual diseases that are causing a lot of scare around the region.  One is the issue of bacterial wilt potentially being a problem on creeping bentgrass.  This issue is one that is going to take some time to resolve, but I don't think that it is nearly as widespread as many think.  The second issue is the one dealing with what I refer to as Pythium patch.  This is not a defined disease as I have not really had the ability to put a major effort into researching it, but the bottom line is that there seems to be a Pythium that selectively impacts annual bluegrass that is not suppressed by the typical Signature applications. My experience with this problem is that you should continue your Signature applications for the more virulent Pythium species and for summer stress, but you should supplement a more traditional Pythium fungicide into your program during conditions like we are experiencing now.

Field Days:
This is a tough time of the year to visit with your local research institutions since the weather is not cooperating, but remember that you can learn a lot of the latest and greatest in terms of management recommendations by attending these events and talking with the University researchers as well as your peers.  This week will see Field Day's by both UConn (July 21) and UMD (July 22).  In the coming week, Rutgers will also be hosting their field day.  Please make any effort that you can to attend these events if you can get away from your course for the day!

Stress stress stress, why a putting green is like a toddler, and localized dry spot

We've had a stretch of hot weather, high humidity, and very high night-time lows. On Monday and Tuesday I had about half a dozen conversations which started with a superintendent saying "everything looked fine Friday, and by Monday it was in a tailspin."

Root problems in putting greens are common this week. If I only had 1.5 inches of roots, I’d be hurtin’, too:

In turf, and in other plants, all the soaking rains have damaged the root systems and now that it is turning hot, it does not take much to push putting greens over the edge. I asked Dr. Jack Fry to give us some pointers on the tricky balance of water management. You can find his comments HERE.

Just scroll down a little bit. That's where you'll learn how putting greens are like toddlers.

Along with compromised rootzones, hydrophobic soils/localized dry spot can sneak up fast in weather like this and cause wide-spread damage in a short time.

Check out the photo below:

The upper inch or so of the profile is fine–the water drops were absorbed instantly and you can see how the soil is wet. And, from 2-inches down is okay too. Unfortunately, there is a stubborn layer of hydrophobic soil from about 1 to 2 inches down. I put the water droplets there, took the photos, then went to work on some other samples. When I glanced over again 30 minutes later, they still had not been absorbed.

If you have known hot spots of hydrophobic soils it is critical for you to keep an eye on them this week, and as long as the heat continues. Get a soil probe and use it. When you water, take some plugs out and make sure the water is actually getting down where it needs to go. Use a wetting agent, and water it in, following all label instructions.

In hot, dry conditions it’s dangerous to aerify, but if we get a stretch of cooler days, you could use solid tines.

Bacterial Wilt of Bentgrass...

I am posting this an "emergency post" since we are all getting a lot of phone calls about it. This message is from Dr. Nathaniel Mitkowski at the University of Rhode Island. Dr. Mitkowski is an expert in bacterial wilt of annual bluegrass.

Bacterial Wilt of Bentgrasses (by Nathaniel Mitkowski, Ph.D.)

The first time bacterial wilt was identified from bentgrass was in the 1970’s. The pathogen, Xanthomonas translucens pv. graminis, only seemed to infect the Toronto C15 variety. This variety was planted primarily around the Chicago area and could rapidly kill turf. Since then, this bacterial species had been sporadically identified but has not been observed causing much damage. In 2003 I found the pathogen in Pawtucket, Rhode Island but it was essentially nonsymptomatic.

In June of 2009, a new bacterial wilt was identified on Penn G2 greens at [Golf Course name removed for confidentiality} North Carolina. The pathogen caused severe etiolation of leaf blades. The isolated bacteria was identified by Dr. Joseph Vargas at Michigan State as Acidovorax avenae subsp. avenae and resulted in wilting and senescence of plants when inoculated in the laboratory. Reports from [golf course] this summer indicate that the bacterium is still causing problems and some turf is being lost. The first report of the pathogen can be found here:

Bacterial Wilt on bentgrass from Dr. Vargas

In the past week, bacterial wilt of bentgrass has been identified at the URI Disease Diagnostic Laboratory at least a dozen times. The bacterium has been identified on L-93, SR1119, and velvet bentgrass. Reports of the pathogen on A4 have also come in. The disease will likely go to any variety of bentgrass. Symptoms include: etiolation, small to medium sized patches of weak turf, turf with excessive senescence and dead plants.

While etiolated turf has been identified from New England golf courses in the past, I have never been able to isolate bacteria from previous samples. The samples I am observing this year are full of bacteria at levels that I have not seen in the past. It seems highly probable that this bacterium requires extended high temperatures and humidity, weather common to the Southeast and similar to the weather pattern experienced in New England over the past 2 months. Superintendents who described seeing this disease in previous years mention that it often goes away completely when daytime temperatures drop into the 70 degree range. It does not appear that a break in the weather is imminent but if it occurs, plant recovery should follow.

Turf video fun, dollar spot in zoysia, hammock accidents, and more!

Two turf videos:

Larry Stowell and Wendy Gelerntner from Pace ( have posted a few videos of turf topics on their new Facebook page.

Here’s a 3-minute demo of fairy ring diagnosis:

And, for fun, a 1-minute clip of a field trial. It uses time-lapse and is pretty cool:

Even more videos!

Syngenta has produced a series of short videos that explains how to take an active ingredient and turn it into a product that is safe to plants, stores well, does not clog equipment, etc.

You can find the video clips HERE

I don’t mean this to be an ad for Syngenta products–it’s just a user-friendly way to learn a little bit about formulations.

Section #3 is the most in depth, about 7 minutes, and discusses how companies use surfactants, dispersants, buffers, adjuvants, etc, to turn a gooey, hydrophobic raw active ingredient into something that can be put in a spray tank and applied to plants.

Dollar spot

The fairway-height zoysia at our turf research center was looking “speckled” this morning.

With a closer look, it appears that dollar spot is present. It is not very common on zoysiagrass here in Kansas, but it occurs from time to time.

Brown patch is also visible in creeping bent plots where it was not present just 2 days ago:

Growth Regulating effects:

The outlined plot is being treated every 14 days with a product that contains the DMI fungicide propiconazole. DMI products can have undesirable growth regulating effects.

Dr. Lane Tredway described DMI effects here:

Dr. K visits Dr. K

I was in my hometown of Madison, WI, over the holiday weekend to visit family. Beautiful weather, good family time, fireworks, Mom and Dad’s cooking… Other than falling out of a hammock and hurting my wrist, which I then aggravated by competing with my brothers in a “crabwalking race” across the backyard, it couldn’t have been better.

While there, I stopped in at the University of Wisconsin-Madison turf research facility, the O. J. Noer Turfgrass Research and Education Facility. You can find a link to it HERE.

Dr. Jim Kerns gave me a tour. At “the Noer,” as it is called, there are a variety of studies going on this year.

Mowing height physiology:

Alternative turfgrass species (such as Junegrass, which is native here in Kansas) for reduced inputs (water, for example).


Phosphorus fertility:

On the disease side, they are looking at snow molds, dollar spot, Pythium, and brown patch. There was a fair amount of dollar spot that day, but somehow I did not manage to get a photo of it. I guess I was too distracted by all the disease.

For me it was interesting to see their set-up, how they organize the field trials, etc. We have some similar interests–disease management, fertility, water use, overall reduction of inputs, etc. It’s always good to get out and see how other people approach things.

Showing off my hometown:

Rainfall and Fairy Rings Throughout the Midwest

Our wet weather has continued throughout the Midwest. Accompanying the wet weather, has been heat- at least heat for us. I feel guilty saying we are hot when I saw the temperatures forecast for the Northeast and Southeast. On the weather channel this evening a couple took a picture of a bank marquee showing temperatures in New Jersey topping 100 degrees! However, we have been in the upper 80's, which is hot for us. Consequently we have seen anthracnose, brown patch and dare I say even some Pythium blight. Don't freak out about Pythium blight because it was only observed near leaky heads or drainage areas.

I have seen a lot of is fairy ring over the last few weeks. It appears to be more prevalent this year compared to last. If fairy ring has been problematic the best way to control the disease is to apply DMI fungicides (Bayleton, Tourney, Triton FLO and Trinity) when 5- day average soil temperatures are between 55 and 65 degress. However, we have moved out of this range in most places in the Midwest. Curatively, an application or two of Prostar (flutolanil) will help alliviate symptoms, especially when the applications follow solid tine aerficiation. If solid tining is not an option than a wetting agent should be tank mixed with the fungicide. Some golf course superintendents have good luck masking symptoms with applications of wetting agents, nitrogen and/or iron. This may be an excellent approach for a large breakout on fairways. If you have more questions about fairy ring, please attend our WTA Summer Field Day on July 27th! Dr. Lee Miller is going to join us to talk about his research on fairy ring.

With respect to diagnosing fairy ring, my best advice is to be like Tucan Sam and follow your nose. The thatch layer underneath the affected area will have a nice mushroomy aroma. You may also notice the thatch may have an orange tint. Another nice technique is to "incubate" a sample in a moist chamber, which is a tupperware container with a moist paper towel underneath the sample. The image below demonstrates the results of an incubation. I still encourage golf course superintendents to send a sample to a local turfgrass disease diagnostic lab if symptoms present themselves in an odd fashion.

Last week I had the great pleasure of showing Dr. Megan Kennelly around the OJ Noer Facility. It was a nice morning and the only disease I was able to show her was dollar spot. One of our putting greens has essentially become a 10,000 square foot dollar spot! I hope one day we can have Megan back to talk about her research on moss and nozzles (just to name a few topics), I think golf course superintendents in the Midwest would enjoy hearing her speak.

Yesterday was another pleasure, a few of us from UW Madison traveled to Whistling Straits to visit with the staff about the upcoming PGA Championship. We had a great visit and we also were given the opportunity to play golf. I cannot wait to see how the pros handle the course this year. I know I had trouble with the long grass a few times! I heard a rumor that John is visiting the Straits this weekend. Wonder if he'll experience the long grass a few times...

Spray, but watch the burn

With temperatures in the high 90s or even triple digits throughout many parts of the mid-Atlantic and Northeastern United States has many scrambling to protect their turf from potential diseases. In addition to the uncharacteristic high temperatures is equally unusual low relative humidity. One common thing in calls that I received this weekend was that everyone was scrambling with hoses.

Another interesting point that I generally don't think about when applying fungicides for field studies is the potential for burn when spraying. In many trials, we only apply a couple of products at a time and rarely mix to the degree that many golf course superintendents. I always joke at meetings about how the record number of items that one superintendent put in the tank was 23! So in light of this and in light of the fact that many are trying to get that next spray out, I received a couple of questions about potential burn when spraying.

In a past post, Lane spoke about the potential negative impact of some of the DMI's on cool-season turf in the summer. In past trials, we have seen some severe leaf tip burning when certain products are mixed together. One product that has gained in popularity is the various phosphites on the market. In some field work, we found that these products can be "hot" and burning can occur specifically when these are mixed with certain products like the DMI's as well as PGRs. Additional things to consider include the use of wetting agents and other products that can add to the potential for phyto. Please leave us a comment or follow the discussion that I started on the Facebook Page here.

Finally, I received a call from a couple of golf courses this week that were concerned about some uncontrollable summer patch on their greens this week. While summer patch may start to show up in this weather and would be fairly typical for this time of year, I call attention to a post on an unusual Pythium species that I wrote about last year. This is something that is relatively new and little is known about it. I can say that it is a real issues, however, and those of you relying on Signature for your sole Pythium control should read this post!

For those of you that follow the LPGA, check out this week's US Women's Open at Oakmont. I am here in the hotel now and ready to spend the practice rounds with John Zimmer's staff and the USGA. Wake up call tomorrow morning at 3:30AM...I am rooting for Christina Kim who just missed out on a win this past week in a four-way playoff!

Check out these photos from last year's Women's Open at Saucon Valley

Save the BBQ for the 4th, not your Poa greens

Superintendent Douglas Reed very carefully checking greens for anthracnose back in the 'good old days' at Arrowhead Country Club (San Bernardino) in 2003 (Doug where are you these days? Hope things are going well!)

4th of July weekend usually kicks off anthracnose season on Poa greens in California, usually its a combination of heat, increased play on the holiday and crews taking a well-deserved few days off. Fortunately, the 4th lands on a Sunday this year and that means that most problems can get caught first thing on Monday. Although most of California looks like its going to be pretty mild this Holiday weekend, guys in the Central Valley with Poa greens should be especially careful with avoiding anthracnose. A little extra prevention with fungicides, some syringing and watching your irrigation before this weekend should help avoid any nasty surprises.

Other than that, there's not much to report from California this week, just a few diagnoses from northern California of brown patch from ryegrass and Poa fairways and roughs this week.

Here in Washington DC (where I'm still hiding out on sabbatical) the heat has finally broken for a few days -- I've complained about this before, but damn it's swampy here in the District. According to Univ. of Maryland alum Matt Marsh (and superintendent at Valencia Country Club) "It's like a Petri plate full of fungus" in the summer. After being here through the hottest June on record, I'd have to agree 100%.

Stay safe over the holiday weeekend!

Signing off from the right coast until next week.....
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