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A Successful Inaugural Year

Well we have made it through our first year (really only about 7 months) of posting for the disease blog and overall I think that it has been a big success.  Overall we had just about 150 posts from the turf faculty.  These ranged from quick updates about things around the region, to more in-depth research results, to a few funny stories and naughty pictures.

2009 Recap
Our Visitors

2009 Turf Diseases Blog Traffic
In our first full month, we had over 2000 visits and as you might expect the peak period of activity was in August and September when turf diseases are at their worst (or best depending on whose perspective you are coming from).

One of the changes I made to our tracking was to install Google Analytics towards the end of the year (mid December to be exact). So the numbers we are getting from are not overwhelming, but they do shed some light on just how far our reach has been not just in the United States but globally.

Global Reach
2009 December Map
Although this data only represents the last 2 weeks of the year (since switching to google analytics) we did manage to reach 640 people from 25 different countries and territories (shown in green)!

Traffic Sources
December Traffic
We definitely want to thank all of those that have added turfdiseases to their own blogs and have driven traffic to the site. This site is built for the sole purpose of informing golf course superintendents about problems that may be on the rise in their area. A special shout-out goes to TurfNet as they seem to have driven a lot of traffic to the site in the past year (not to mention in the last two weeks.)

I would also like to thank the folks at GCSAA and Golf Course Management for their mentions of the blog.

A Look Towards 2010

Towards the end of 2009, you probably noticed that we had less than consistent postings.  This was expected as the disease problems started to slow down in most areas and teaching responsibilities and conference season picked up for most of us.  While we can't promise a post every day of the week, I can assure you that next year we plan to get back into the swing of things.

In addition to our routine postings about current disease topics, look for some special "guest" posts from colleagues in the United States and other parts of the world.  With the apparent interest in the site from other countries, and upcoming international trips for some of the primary pathologists on the blog, we plan to initiate an "International" posting date during the year.  Again, this will not occur every week, but weekend posts have been reserved for postings from other parts of the world.  Just some potential regions include posts from Asia, Argentina, The United Kingdom, France, and South Africa just to name some.

As always, I wish to thank the readers of the blog and ENCOURAGE you to participate publicly or privately.  Although the authors would like to get out to every section of their region to find out exactly what is going on, sometimes this just isn't possible.  So send us an email or photo and let us know what is happening in your area during the year.  Your information may prove invaluable for a fellow golf course superintendent in your region or another part of the world!

Signing off from 2009...(looking forward to getting my "drink on" tonight). CHEERS!

Snow in the Northeast, Dormant turf in Dallas

This week, I had the opportunity to visit a couple of golf courses in the Dallas region. While I was touring these courses, the entire Northeast was getting pummeled by one of the largest snow storms of the century (thank goodness for the #snOMG posts on twitter, otherwise I wouldn't have been able to keep up with it).

Anyway, since the entire Northeast is currently under anywhere from a few inches to a foot or more of snow, I thought that I would give a special post for those in the Dallas area.  My visits took me to the Dallas National Golf Club and Colonial Country Club.  These 2 courses provided a unique opportunity to see a mix of both warm-season fairways/roughs and cool-season putting greens.  Recent cold temperatures shut down the growth of the bermudagrass (Colonial Country Club) and zoysiagrass (Dallas National) fairways and slowed the growth of the bentgrass putting greens.  The greens were in excellent condition at both clubs and disease issues were few and far between.

During the season, diseases that can often be found on the course include fairy ring, spring dead spot, and large patch.  In fact, there was a few remaining patches of large patch on the zoysia in the practice facility where fungicides are used on a limited basis.  Control of the patch diseases is being managed with fall and spring fungicide applications.  As you can imagine, the major issues at the courses are seen during the heat of the summer when severe stress is put on the bentgrass putting greens.  I hope to get back sometime to see the course in these conditions...a pathologists dream!

Other issues which I don't typically get to deal with included the development of algae in some of the bunkers and the management of warm-season encroachment into the bentgrass putting greens.  I hope to be able to pass along some information from our GCSAA algae grant which is currently in progress.  Although the project's goal is to manage algae on putting green turf, I am interested to see if some of our findings could translate to the bunker sand as well.

The visit with Scott Ebers and Brannon Goodrich was great and I appreciate their hospitality in showing me around the course.  Both courses were in excellent condition and unique.  Colonial with its rich history and long-standing relationship with the PGA and Dallas National with its unique zoysiagrass fairways and spectacular views are must a must see for anyone interested in golf OR interested in growing bentgrass in some of the most difficult environments.  To me, this would be like growing Poa greens in the mid-Atlantic...not an easy task during the intense summer months.

Despite being in Texas, we were impacted by the storm as all flights from Dallas to Philadelphia were canceled on Sunday and here I sit in the airport on Monday writing a new post. I just hope that we make the earlier flight (currently on standby), because if we don't we will not get home until ~11PM. I did post an image above of Dallas National taken from my phone, but I will have to wait until I get home to upload photos from the course.

Another Good Winter for Snow Mold

As Megan mentioned we got hammered with snow last week. The total snowfall amounts vary but we received over 15 inches of snow! Yes it took me most of the day on Wednesday to clear my driveway, but a wonderful neighbor used his bobcat to clear "plow trash" at the end of my driveway. The picture was taken last Wednesday morning and I was clearing a path for my dog to use the restroom. Following the snowfall, temperatures plummeted! The high last Thursday was 7 and the low was -4, so I think the snow is going to stick around a while.

With the amount of snowfall we received last week that fell on unfrozen ground, it appears that this winter is going to be conducive for gray snow mold development. Gray snow mold is induced by two Typhula species- T. incarnata and T. ishikariensis. Other names for the disease are Typhula blight and speckled snow mold. All cool-season turfgrasses are affected by gray snow mold, but the degree of severity differs with turfgrass species and the length of snow cover. Persistent snow cover provides an ideal environment for the gray snow mold pathogens to thrive and infect turfgrasses. If snow cover persists for more than 60 days than gray snow mold is likely to be problematic. When snow cover persists for more than 90 days, gray snow mold is often very severe. It is important to have an idea of how long snow persists in your location to develop a successful gray snow mold management program. Fungicides that are efficacious in areas with low to moderate snowfall may not be effective in areas with high snowfall amounts. I know I have posted our snow mold trials before, but it never hurts to repeat things. The reports clearly state how much snowfall was recorded at testing location. So pick the most appropriate site based on your conditions and hopefully you can find a chemical or mixture of chemicals that work for your budget.

What happens if we experience a winter thaw do I need to reapply fungicides? This is a question we routinely get, however I have yet to experience a winter thaw. I know I have only been here for one winter, still the last couple of winters have been fairly harsh. It is frivolous to apply fungicides when the ground is frozen, so that is the first thing to check. If the ground is not frozen then the answer is maybe. We are working with commercially available ELISA (enzyme-linked immunosorbant assay) kits to determine how long chlorothalonil and iprodione persist under snow cover and in the absence of snow cover. This technology is used to determine fungicide concentration in fleshy fruits like apples. We have just received some new data that demonstrates that our extraction method works very well and we are eagerly working on collecting degradation data this winter. Along with determining how these fungicide degrade, we are performing inoculations in the growth chamber to figure out when we lose protection to Microdochium nivale. There is more to come with this research so please stay tuned!

One interesting side note we learned from this project is the actual concentrations of the pesticides in the bottle/tank and what is detected on the plant. For example, Daconil Weatherstik is 54% chlorothalonil, when mixed in 2 gallons of water per 1000 sq ft the concentration of the solution drops to about 16 %. Then once the chemical is applied and allowed to dry for one hour we can detect about 600 parts per million on and within the leaf. I don't know if anyone else thinks those are interesting numbers, but I sure did. This spring we are going to repeat this experiment and we plan to include a sample to test fungicide concentration directly from the nozzle.

Best wishes for a happy holiday season and a happy new year to all of our readers! I am heading to North Carolina this Saturday for the holidays, so this will likely be my last post for the year. Thanks to all of the readers and thanks to John for putting the blog together!


Kansas Snow Conference, I mean, Turf Conference

Hello from a cold and snowy Kansas,

Yes, I know the 6-8 inches we got here can't compete with the 15+ inches Jim experienced up in Wisconsin. He's probably barely shoveled out his driveway by now. But, 6-8 inches is big news for us. As a native of the north country, I'm a big fan of snow.

Unfortunately, the snow did put a little bit of a damper on our Kansas Turf Conference which was Tuesday-Thursday over in Topeka. Some folks could not make the drive (I myself saw plenty of cars in the ditch on I-70 on the drive over), and many of our usual participants from the lawn and landscape side of things were busy out making money on their snow-plowing contracts. But, we still had fairly good attendance and on the upside, those that were there got extra attention, and extra donuts.

Our out-of-state speakers this year were John Stier from U of Wisconsin. I'm not sure how he dodged blizzards on both ends of his travel, but he did make it in. John was a highly energizing and entertaining speaker. We also had two speakers from Oklahoma State, plant pathologist Damon Smith and entomologist Eric Rebek. Both of them provided great updates from our neighboring state to the south. In from the east coast was Grady Miller from NSCU. Grady was a favorite in our athletic field workshop. Finally, we had some USGA updates from Larry Gilhuly.

Thanks to all who braved the weather to come on out.
At the conference, I continued my multi-year dominance of my category in the "longest drive" contest. Our student GCSAA chapter sets up a camera and some netting, and as a fundraiser for them you can pay a little bit to enter the competition. Of course, I also came in LAST place in my division. As one of the few women at the turf conference, and the only one who ever enters, I always win first place while simultaneously coming in last. My score was 198, which was beter than last year's ~120 (I'm not very good!)

Finally, over beer one night, I heard one of the more funny things I've heard in awhile, "You know you are getting old when ibuprofen is your drug of choice."

Switching topics, you might remember I posted a photo of some striped chilling damage in bermudagrass awhile back. I'll post that again here. A week or so ago, someone emailed to me the second photo, showing frost in some fescue. It's a little hard to see with the shadows, but that certainly looks like the same type of pattern, eh?
To wrap up, last time I mentioned some yellow patch and in the follow-up comments there was some chatter about brown ring patch. We did confirm in the lab that the fungus was indeed the yellow patch pathogen. So far, brown ring patch has not been detected in Kansas but I'm keeping my eyes open.
And, Frank, don't worry about publishing on Friday. Actually, I think we should ALL post something on John's day, just to get him riled up :)

Brown Ring Patch, Polyoxin-D & Savage Pathology Style Q&A

Sorry for barging in on Megan's Friday posting but better late than never :)

Brown Ring Patch on Creeping Bentgrass in Arizona?
Gabe Towers (Target Specialty Products) in Arizona sent these pictures in from a creeping bentgrass green at a course outside of Phoenix. According to his observations, it's definitely a Rhizoctonia-type disease and the mycelia and symptoms look an awful lot like what we would expect brown ring patch to look like on bentgrass. Unlike the bright yellow rings associated with the disease on annual and rough bluegrass, brown ring patch on bentgrass makes nice brown sunken rings. These symptoms are like those first described for the disease orginally in Japan on this turf type.

One of the things that we're seeing here is also the development of patches without rings. Although rings are typically seen with the disease, we did isolate Waitea circinata var. circinata from similar patches in Idaho last year.

The most compelling evidence for brown ring patch would be the presence of aeial mycelium after incubation plus the sunken degraded thatch on the greens.

We're working with Gabe right now to confirm the pathogen identity, but if it is brown ring patch, that'd be a first for the disease on creeping bentgrass in Arizona.

Polyoxin-D: Soon Available in Two Fruity Flavors!
Well, not really. Polyoxin-D fungicides kind of smells like Top Ramen to me. Polyoxin-D has proven to be one of the best fungicides for brown ring patch control and will soon be available from two companies in 2010. There's a little bit of a backstory on this one, but I'll skip the details and just say that two formulations from two different companies will be available soon.

Endorse 2.5WP is now part of Arysta's line of turf fungicides. It was previously marketed and distributed by Cleary Chemical, and we should expect no major changes to the label and the use rate will continue to be at 4 oz per 1,000 sq ft.

Cleary Chemical will now be selling Affirm 11.3WDG. This has about 4x more polyoxin-D than Endorse, so the expected use rate will be 1 oz per 1,000 sq ft.

For more information (as it becomes available) please see the maunfacturer websites:

Question of the Week
This is kind of a new feature for the Left Coast blog, but inspired by columns such as Dear Abby, Car Talk, and Savage Love, and the slow down of info this winter, I'm going to try to post Q&As recieved by email.

Hi Frank,

I am looking for a third product for snow mold control on poa greens (monterey peninsula). My curent rotation is Instrata followed by Chipco GT every 14 to 21 days depending on the disease pressure. I was considering Eagle in combo with Fore any thoughts?

Thanks in advance,
Moldy in Monterey

Dear Moldy -

Pink snow mold in California can be tricky since it can fire at cold (< 65F daytime temps) and wet conditions without snowfall. As you know, it can go from 50 to 80F in a week in parts of California during the winter, especially in southern California, making this disease somewaht unpredictable. As such, creating a clear, defined pink snow mold (aka Microdochium patch) preventive fungicide program can be dififcult and often superintendents end up making a lot of curative applications for this disease. Please look at page 16 from Paul Vincelli's (University of Kentucky) overview of turf fungicides - the ratings are based on the average of trials performed for the last 10 or so years over all of the US.

Can you use PCNB? If you consistently stay below 70F during the winter - PCNB is really useful - long lasting, no resistance, cheap - but, if it goes over 70F, you can potentially get burn and or root pruning at high rates. Maybe target PCNB apps for the coldest part of the year , saving your Instrata applications for times when temps can get warmer.

Since Instrata = Banner + Medallion + Daconil, Medallion and Daconil are probably limited as alternate rotation partners due to label rate limitations.

You can use another DMI (Banner, Eagle, etc..) in the rotation since DMI resistance really hasn't been an issue for pink snow mold yet - but as you can see from Paul's chart, some DMIs work better than others. It'd probably be a good idea to mix this application with something else for added protection. As you indicated, mancozeb (Fore) is a good choice in your case.

I think the QoIs (Heritage, Compass, Insignia, Disarm) can be dicey for snow mold control; we've seen a few cases of resistance in CA, but this topic needs a lot more research. Thiophanate-methyl should be used with caution, resistance has been around in WA since the 1980s.

Finally, good call on the Chipco 26GT as a rotation partner. Since tolerance may be an issue in some places, keep the rates on the higher end or mixing with a contact such as mancozeb in your rotation may help.

How's that sound?


That's it for this week. Signing off from the Left Coast.....

yellow patch/cool season brown patch

I've been pretty quiet lately. No international adventure trips like John, no potpourri of diseases like Frank is seeing.

The most interesting thing is that there has been a little bit of yellow patch (cool-season brown patch). In Kansas, we most typically see this disease towards the end of winter, like in late February/early March (that is when the photo was taken). But, the pathogen (Rhizoctonia cerealis) can certainly be active at the temperatures we have been seeing lately.

One superintendent noted that he tends to see yellow patch more in greens that are primarily (>80%) Poa annua, not bentgrass. I have not noticed that myself but am wondering if others have seen the same trend.

Another interesting turf disease issue this fall is a tremendous amount of powdery mildew. The fungi which cause powdery mildew do not require leaf wetness, but they do appreciate some humidity. We've had a wet autumn, so that has probably increased the disease pressure. In some shady areas there's so much powdery mildew that it looks like someone sprayed white paint on the ground.

No Fun

I hope everyone out there had a great Thanksgiving last week!

Here in California, it's been pretty slow in the Wong Lab. Things are getting pretty cool here (by California standards) and here in the picture, you can see our Tifway-II is pretty much headed into full dormancy in Riverside with our soil temps in the mid-50s. My PhD. student, Chi-Min Chen, and undergrad lab assistant (Erica Serna) are helping me inoculate plots with Ophiosphaerella korrae - one of the causal agents of spring dead spot. I heard the comment of 'this is no fun' a few times this morning which reminded me of a joke my mom told me when I was a kid. It kinda goes something like this:

Q: "What was the name of the first Chinese test-tube baby?"
A: "No-fun Son"
(apologies to the defenders of political correctness out there)

For those who didn't get that maybe this will help:

The 'maladie de la semaine' continues to be rapid blight on annual bluegrass greens - temperatures in the 60s-80s and a lack of substantial rainfall is allowing salts to continue to accumulate and cause conditions that favor rapid blight.The half-inch of rain that we got in parts of California last week didn't help much in knocking salts & sodium down, e.g. we need substantial or consistent rain to help us flush out the last several months of sodium accumulation on greens.

However, we're expecting some rain and showers, especially in northern and central California starting this weekend /early next week and lasting for a few days. That's great news as far as knocking down salts but bad news as far as Microdochium patch/pink snow mold.With a few days of moisture and daytime temps < 65F, we'll likely see some pinkie firing on annual bluegrass. If you don't already have a preventive fungicide application down, it'd be a good idea to squeeze one out before the showers and rain start in the next few days.

Signing Off from the Left Coast Until Next Week....

Highlights from the 44th Annual Wisconsin Golf Turf Symposium

Like Megan, I have also been very quiet. Snow mold fungicide trials dominate our time during the late fall and I am happy to say we have put another snow mold season to rest. At least the applications are complete, now we patiently wait for the snow to fly! I know this comes as a huge surprise to some, but its pretty chilly in Wisconsin. This has not been the norm however. We just experienced one of the warmest Novembers on record. Although our temperatures were warm, we have not seen or heard much from anyone in the Midwest. So I thought I would take the opportunity to talk about the Wisconsin Golf Turf Symposium held Nov. 17 and 18 at the American Club in Kohler, Wisconsin.

The speakers included Stuart Lindsey (Edgehill Golf Advisors), Todd Quitno (Lohmann Golf Designs), Dr. Frank Rossi (Cornell University), Bob Vavrek (USGA Green Section), Dr. Eric Watkins (University of Minnesota) and myself. Mr. Lindsey lead the meeting off with a grim depiction of the golfing population. The golf population is declining to 1990's level with most of the golfers exceeding 55 years of age. Mr. Lindsey then provided advice on how to reduce costs or at least ways to identify where the majority of the golf course superintendents' budget is spent. He recommended that golf course superintendents' do time studies to determine if the maintenance operation can become more efficient. He also presented data indicating the main reason people are staying away from golf is time. They do not want to play a 4.5 hour round. Mr. Lindsey's was not all gloom and doom. He said that supply is meeting demand due to the halt of golf course construction and golf course closures.

After Mr. Lindsey, Dr. Rossi took the stage and talked about the Bethpage project and on the second day spoke about sustainable golf turf management. Dr. Rossi demonstrated that a purely organic golf course is not an option for a course like the Bethpage Green Course. He then outlined their alternative cultural practices and IPM program. The cultural practices they enacted were reduced mowing frequency with supplemental rolling, increased rolling frequency, only N, Fe, and Primo were applied, topdressing was performed every 7 to 10 days, solid tine or water injection was conducted every three weeks and spiking was performed weekly. When this program was coupled with an IPM program- that developed historical records, managed plant health, utilizes predictive models, used EIQ values to determine pesticide usage, treated preventatively and focused on playability- reduced product expenses by 20 to 40 %. They determined this by comparing their alternative method to methods commonly used by golf course superintendents.

On the second day Dr. Rossi spoke about sustainable golf turf management, which focused on climate change and carbon sequestration. The take home message from this talk was to think about climate change and to find ways to make a golf course carbon neutral. Dr. Rossi's group determined that a conventional management strategy and the alternative management strategy were carbon neutral. I got the indication that turfgrass plants are pretty good carbon sequesters. No matter what your particular views about climate change or sustainability, I think Dr. Rossi's presentations had some very good points. I encourage you to contact him if you have anymore questions about these to particular presentations.

Dr. Eric Watkins presented on low-input turfgrasses. Basically there are more options coming for low-input fairway and putting green grasses. Many turfgrass breeders, including Dr. Watkins are working on improving agronomic and disease resistance traits of grasses like colonial bentgrass, velvet bentgrass, tufted hairgrass, and tall fescue just to name a few. I especially enjoyed his table presenting the NFC North standings to a Wisconsin audience! That took guts!

Bob Vavrek talked about developing maintenance standards. He stressed this so the golf course superintendent has clear goals that are attainable. It also allows for accountability. He presented a case study from Baker Hill Golf Club. They had maintenance standards outlined as well as links to USGA Green Section articles on rationale for fixing ball marks and aerification. Mr. Quitno presented design methods that reduce expenditures. For example on one particular case, they reduced teeing areas substantially and increase air movement to tees and greens. He also demonstrated the cost differences between different bunker designs. I had no idea that renovating bunkers could be so expensive!

Essentially the take home message from the meeting for me, was to try and find ways to mow less. And to start thinking about ways to reduce pesticide expenditures. It was a fantastic meeting and I was honored to have the opportunity to speak this year.

Turf Management in the UK & Europe

Two weeks ago I mentioned the posting of an international update from a recent trip to Europe and the UK. While overseas, I had the chance to speak with the Dutch Greenkeepers Association and the greenkeepers of the Southwest Region of the British & International Golf Greenkeepers Association. The trip was a great opportunity to visit a couple of golf courses in Holland and also hear about some disease updates in the UK from Ruth Mann of the Sports Turf Research Institute.

Golf Course Visits:
While in the Netherlands, we took a day trip to visit two golf courses including the Kennemer Golf Club (site of the Dutch Open) and the Golf Club De Pan. Both courses were very unique and a treat to see. One of the most unique aspects were the Nazi-built concrete bunkers at the Kennemer Golf Club. These were constructed during the Nazi occupation of the Netherlands during World War II. These bunkers are still used on the course for the maintenance facility as well for several storage areas for maintenance supplies and equipment.

From a disease perspective, there was plenty to see, but not enough that caused much concern for the greenkeepers as playability did not appear to be impacted. The main problem with playability came with the earthworm castings on the fairways which was causing severe problems. Other common problems appeared to be fairy ring and red thread. Interestingly enough, most of the damage on the fairways had the visual symptoms of dollar spot, but closer examination of all of the spots revealed the presence of red sclerotia. There is a good possibility that this was a complex of the two diseases, but without isolation it was impossible to tell if dollar spot was also involved. In addition to these common diseases, we also saw a few areas with yellow tuft, which was really of no surprise due to the excessive amount of precipitation that the area had received during the year.

Earthworms continue to be a large problem for greenkeepers.

Disease Update from Ruth Mann:
Ruth Mann manages the Turfgrass Protection Department of the STRI and has extensive experience dealing with disease on golf courses in the UK. Dr. Mann gave a great update on turfgrass diseases in the UK. According to Ruth, dollar spot and leaf spot diseases are definitely on the rise in the UK. Ruth made specific mention to the changing weather in the region and revealed that temperatures have increased by 0.15C in the past few years. She also lightheartedly mentioned the mote that she had to drive around to get out of her hometown to make it to the meeting after some major flooding in the UK (Story here). Ruth went on to caution turfgrass managers about curative control of chronic dollar spot in particular as it is not always the most effective. Other diseases that continue to be a problem included Fusarium patch (Microdochium patch, aka Pink snow mold) and of course fairy ring.

Fairy Ring and Other Issues:
My talks involved a discussion of the principle of managing fairy ring, a disease that greenkeepers in the UK and Europe are all too familiar with. However, management practices that superintendents in the US often take for granted are now just becoming increasingly popular overseas. Some of these practices include the use of wetting agents and the use of the plant growth regulator trinexapac-ethyl. While these supplemental cultural practices are resulting in improved turfgrass health and quality, they are being met by an increase in management intensities. For instance, there was a debate among some of the greenkeepers in the UK regarding mowing heights. While most felt that keeping heights around 5 mm (~0.2") is going to make for a sustainable turfgrass, others felt that lowering heights as low as 2 mm (~0.079) is manageable (remember that many of the greens are fescue and highland bentgrass, not the typical creeping bents and Poa managed in the northeast). Additionally, there is increased interest in the idea of minimal disturbance (no hollow cultivation) and reduced nitrogen fertility. Perhaps I am just cynical, but it appears to me that in the greenkeepers attempt to meet the powers-that-be's goal of "sustainability", they are basically heading down the road of turf management practices of the United States. These practices will likely be met with more intense disease pressure (as they now seem to be seeing). Whether the increased disease pressure is the result of rising temperatures or changes in the weather patterns OR whether this is the direct result of more intense management practices will remain debatable.

In the United States, golf course management seems to go in cycles (graph courtesy Adam Moeller, agronomist for Northeast green section of USGA). Ten to fifteen years ago, turf managers were on a kick to keep it "lean and mean" (and many still subscribe to this) and were met with increased outbreaks of dollar spot and anthracnose. In fact, these two diseases are probably the most important diseases of golf course turf in the Northeastern United States. Superintendents also continue to utilize PGRs and improved equipment to reduce mowing heights to sub 0.10" heights in an effort to chase green speeds for the membership. Luckily, most superintendents are now getting a better handle on adjusting seasonal fertility rates to manage these diseases. Unfortunately, it doesn't look like mowing heights will ever go back up from the extremes we have pushed them to. My point? It seems to me (albeit with limited experience with turf management in the UK and Europe) that if turf managers overseas continue down the road they are currently on, their turf will be met with increased percentages of Poa annua and increased dollar spot and other low N or excessive-thatch diseases. This will ultimately result in the need for increased fungicide use, which is the exact reason the idea of "sustainability" has become widely promoted by the R&A.

My final thoughts:
In discussing these issues with greenkeepers in the UK, I found that there is much internal debate on some of these topics. The best argument I heard was that "the more we do, the more problems we seem to have." I agree completely, but the challenges are the same as we have in the United States (envy and egos). Once golfers see the quality of the course down the street (whose greenkeeper is not letting nature take its course), they are going to start asking for similar conditions. And so the cycle will continue.

A special thanks to our hosts
This was a great trip and I appreciate all of the warmth and hospitality shown during the tour (and I look forward to the Scrumpy on my next trip). I truly love golf and golf course management in the UK and Europe. Despite all of the "advances" and demand for increased turf quality in the US, the fact that golf in the UK/Europe is still about the playability and not (not yet) about the emerald green look says a lot about priorities surrounding the game of golf.

Check out some photos from the trip below.

Still Wild in the West

With the cooler temperatures here in the West coming in, you'd expect some slow down as far as disease development, NOT! Rapid blight and basal rot anthracnose continue to be issues on Poa greens in California. We're also seeing some junk diseases like Curvularia blight on warm season turf slowing down in the cool weather and algae developing on greens with the reduced day-lengths.

California Disease Summary
Dr. Naveen Hyder did a nice summary of the last four years of disease diagnostic data at the Crop Science Meeting in Pittsburgh a few weeks ago. A copy can be found here:

As you can see, Poa annua diseases like rapid blight, anthracnose, brown ring patch and algae are our top trouble makers, with over 50% of our samples being annual bluegrass, Naveen stated to the crowd "either we need to put even more resources towards annual bluegrass disease control, or figure a way to keep it out of greens." Much, much easier said than done....

Pythium in the PNW
As mentioned a few weeks ago, Pythium has been causing issues for superintendents in Oregon and Washington. We finally got an ID on some of the troublemakers involved. Samples from several courses were identified as having either Pythium vanterpoolii or P. torulosum, which can do perfectly well under cool (55 to 65 degree F) conditions, as long as its wet. I haven't had much experience first hand fighting these, but my gut feel is that under cool, wet conditions, many typical fungicides can knock down the Pythium, but it's too cool for the annual bluegrass to recover quickly. If it stays wet, the Pythium can re-emerge when the fungicides have "worn off" and damage turf again. In this situation, the lack of recovery from the turf due to cool conditions just magnifies the sucessive rounds of damage and frustrates the hell outta superintendents.

Annual bluegrass greens damaged by Pythium at Portland Golf Club (left) and several weeks later after multiple fungicide applications, blood, sweat and tears (right). Images from superintendent Forrest Goodling.

Thiophanate-methyl and Pink Snow Mold in Northern California
An interesting question was brought up to me this week about using thiophanate-methyl on annual bluegrass greens in parts of northern California. Some superintendents are using it to manage a problem (hint: rhymes with angina) and were wondering what the impact of that would be on resistance development for pink snow mold, which should pop up as our max. daytime temps start to drop below 65.

If one's using repeated thiophanate-methyl applications at a time when pink snow mold may be active - resistance is certainly an issue. Resistance to the benzimidazole fungicides (benomyl and thiophanate-methyl) was detected for pink snow mold back in the 1980s in Washington State. It's unknown what the current status is in northern California, but certainly, back to back, repeated applications of this fungicide will be putting one at risk for losing it for pink snow mold.

If one is using this approach, make sure to use other materials as front-line fungicides for pink snow mold control. PCNB, iprodione, polyoxin-D, the DMIs, mancozeb, & chlorothalonil and mixtures of some of these are all non-benzimidazole fungicides that can be against pink snow mold.

Signing off from the Left Coast until next week......

The Disease Triangle (part 2): The Host

Everyone that has sat through a pathology or disease lecture has heard of the disease triangle. Consisting of the environment, the pathogen, and a susceptible host, the disease triangle is a critical component of understanding disease pressures on a golf course. In a previous post I talked briefly about the importance of the environmental (weather) component of the triangle. I thought that as we wrapped up the season in the Northeast, I would take this time to speak about the importance of the host.

Unlike cropping systems where the purpose of the host is to grow a plant as large as possible and harvest it for sale or distribution, turfgrass managers must deal with a perennial crop that hopefully remains healthy forever (or at least for a long period of time). So instead of just trying to get to harvest, we must figure out a way to manage the "crop" during the good times and the not-so-good times. In the Northeast, just about all of the typical cool-season turfgrass species are grown and in the transition zone of the region we even grow a few warm-season turfgrasses. Growing grass in this region can be very difficult. Taking the extremes in weather out of the equation, there are still some important things about the host to take into account when identifying and managing turfgrass diseases.

When I first take a look at a turfgrass sample, identification of the genus and species is the first step of the process. Remember to look for key attributes including the vernation, ligule size, leaf tip, growth habit and other key components, Simply identifying the species can eliminate numerous pathogens as potential causes of the problem in question. For example, take-all patch is primarily a disease of creeping bentgrass. If the species affected is primarily annual bluegrass, then this disease can be ruled out (not to mention that take-all is primarily a disease of young putting greens of which little ABG would be present). To the contrary, a patch disease appearing primarily on annual bluegrass could limit the possibilities to summer patch or necrotic ring spot (or possible nematodes). Although summer patch may be present on bentgrass in the extreme heat of the Southeast, it is rarely (never to my knowledge) been identified on bentgrass in the Northeastern United States.

So being able to identify the species at your course can save you a lot of time and increase your chances of making an accurate diagnosis. There are too many diseases to talk about in this post, but below are some common hosts of typical diseases found in the Northeast.

Anthracnose basal rot: primarily annual bluegrass, occasionally creeping bentgrass (does not occur on both species on the same green)

Brown patch: most species, but tall fescue, perennial ryegrass, and bentgrass (particularly colonial bentgrass) are most susceptible

Dollar spot: all species susceptible, particularly important on bentgrasses

Summer patch: Kentucky bluegrass and annual bluegrass, also fine leaf fescues

Take-all patch: creeping bentgrass

Sometime prior to the end of the year, I will wrap up the discussion of the disease triangle with every pathologists most favorite component...the pathogen!

For a disease update, things are just about shut down, but dollar spot did pop up in recent weeks and microdochium patch continues to be active at select regions in the Northeast.

Microdochium patch running amuck!

Thanks to the lovely weather we've been experiencing in the Midwest, Microdochium patch has probably worn out its welcome. We just went through the second coldest October on record and I think one of the wettest! Absolutely perfect weather for Microdochium. Microdochium is a pathogen of many turfgrass species and can be especially severe on cool-season turfgrasses. The symptoms appear as small (<6 to 12 inches) water-soaked patches in absence of snow cover. Affected plants are blighted and may have a greasy appearance or may be a tan color. Stand symptoms can also have a pink or salmon hue evident after snow melt. Also symptoms tend to more severe after extended snow cover.

The conditions that favor disease development are cooler temperatures ( 32 to 60 F), high humidity and high nitrogen content in the leaf tissue. Snow cover is not required for this disease to develop, but is usually more severe when snow cover occurs. Microdochium management is fairly simple because many chemicals are efficacious. The tried and true combination for many people is a tank mixture of chlorothalonil and iprodione. Avoiding late season fertility applications seem to limit Microdochium symptoms. The exact timings to avoid are not know, but we are examining that particular question this winter.

Just returned from Pittsburgh attending the Turf Nerd Conference as John put it. The Agronomy Meetings are my favorite time of year. The graduate students at the meeting give fantastic papers and it is a real joy to find out what all of us are doing. For those that are not familiar with these meetings, our division C-5 is the second largest division in the Crop Science Society. Yet the camaraderie amongst the members of the division is great! I've heard that Pittsburgh was not a nice location years ago, but I really enjoyed my stay in Pittsburgh. Unfortunately I did not make it to Primanti Brothers. I did not have a bottle of Pepto with me and just getting over my recent battle with the flu I did not want to chance an upset stomach. Next time the corned beef and cheese sandwich is mine!!

The Turf Nerds go to...

...Pittsburgh? It figures that in the year that I take a new position at Penn State, the annual Crop Science meeting ends up in Pittsburgh. In the past 4 years, the show has been to Salt Lake City, Indianapolis, New Orleans and Houston. Well, in a year where budgets are slim and we are all trying to scale back it was probably best for me. I just feel sorry for those having to make the trip from the West Coast.

So what is the CSSA-ASA-SSSA annual meeting and why is it a hotspot for all of the turf nerds across the country this week? Well, this scientific tri-society of crops, agronomy and soils is probably the largest scientific conference for those university and industry personnel to catch up on the latest and greatest scientific research from around the country. If you are not familiar how scientific discoveries are made, just know that it is not an overnight occurrence. It generally takes several years to develop a solid project, find a graduate student or technician to assist with the work, analyze and write the results and then submit them for scientific publication. The last part (publishing in a scientific journal) can often take up to one year from the time of submission to the time that the research is actually seen in print. Then it takes another few months for the scientific publication to be rewritten in a format that anyone in the industry would actually be interested in reading before making its way into Golf Course Management, Golf Course Industry, Golfdom or similar trade magazine. So from start to finish, a project may take 3 or more years to go from idea to print.

So why do we go to these meetings each year? These meetings are the pinnacle of the latest discoveries in the field and allow for scientists to share ideas and form possible collaborations to advance the science more quickly or more completely. The information presented is usually the latest and often represents preliminary results to studies that are just getting off the ground. Presentations are given orally or as posters and graduate students even compete against each other for the top presentations in each category (I am actually one of the judges for oral presentations this year). Faculty also present their latest findings and industry representatives provide insights into what is happening on their side as well. The week is culminated in the business meeting where outstanding achievements are recognized and actions are put in place for the next year.

So I am off for Pittsburgh this morning (immediately following my class) year I am looking forward to Long Beach, CA!

Check out my list of interesting topics for this week...
Glyphosate-Resistant Annual Bluegrass (Poa annua) in Missouri.

Physiological Changes During Cold Acclimation for Perennial Ryegrass Accessions Differing in Freeze Tolerance.

The Effects of Nitrogen and Trinexapac-Ethyl On the Severity of Brown Ring Patch On Annual Bluegrass Golf Course Putting Greens.

Developing a Predictive Model for Spring Germination of Smooth Crabgrass (Digitaria ischaemum) and Annual Bluegrass (Poa annua) in Michigan.

Sodium Adsorption On Calcined Clays and Zeolites.

Above image used under creative commons license by author

The turf is chillin'

I was at Oklahoma State University yesterday to give a couple of presentations at a tree workshop. ("Are you pining for healthy pines?" hah, clever, eh?? maybe not...). My OSU colleagues Damon Smith (plant path), Eric Rebek (entomology), and Mike Schnelle (hort) were great hosts and they also gave some excellent presentations.


Just outside the door.... was the OSU turf research center, and I was excited to find this symptom (in the above photo) in some bermudagrass.

What is going on here?

This is a form of chilling injury. Chilling injury like this usually occurs when temps are between about 32 and 54 degrees. Symptoms tend to appear 24-48 hours after the chilling event. The bleached out areas are due to degradation of chlorophyll. Why the funky pattern? Nobody knows for sure, but it may have to do with small-scale differences in where the coldest air settles.

Ohio State has a collection of podcasts, and there is one that addresses chilling injury.,com_wrapper/Itemid,78/

Then, go to the December 2006 section of the archives (blue list on the right).

Or, go to this site:

And scroll down about halfway and you’ll see the file for Chilling Injury. You can click and either run it or download it to view later.

The Most Wonderful Time of Year

We are in the midst of snow mold season in the Midwest, or at least Paul and I are traveling all over Wisconsin, Minnesota and the Upper Peninsula of Michigan. This year we have two sites in Minnesota- Edina Country Club in Minneapolis and a golf course in Baxter. The site in Baxter Minnesota is 100 miles from Fargo North Dakota and we have ventured up there to get a better handle on snow scald control. We received a lot of samples from that part of the country and superintendents have had difficulty controlling that disease.

We have two sites in Wisconsin-Sentryworld Golf Course in Stevens Point and Milwaukee Country Club in Milwaukee. Sentryworld is our old faithful site as it usually yields good snow mold pressure every year. However, we found out last year that treatments that work in Stevens Point may not necessarily work under extreme pressure. So we decided to venture to the UP of Michigan. Last year the snow mold pressure was intense in Champion Michigan and I suspect it will be again this year. We travel to all these sites to provide golf course superintendents the best possible recommendations for snow mold in there area. So check back with us next year when we finalize our trials, should be interesting.

On another note, I agree with Frank- the flu sucks! I have come down with the flu and I think it is the first time I have had the disease. Wow does this disease take the wind out your sails. I know I promised posts on all the different snow molds and I will do so starting next week. Sorry for the short post this week.

Effects of DMI Fungicides on Bermudagrass Putting Greens

Those of you that follow this blog know that I am not a big fan of using DMI fungicides on creeping bentgrass and annual bluegrass putting greens during the heat of summer. The impacts of these fungicides on bermudagrass greens, however, are not as well understood. Some of the newer DMIs, like Trinity, Triton and Tourney, are not labeled for application to ultradwarf bermudagrass varieties. Even though these products are safer on the cool-season grasses, they can cause severe phytotoxicity and thinning of 'Champion', 'Tifeagle' and 'Miniverde' greens.

A recent trial we performed on 'Champion' bermudagrass in Rocky Mount, NC showed some unexpected results. Each fungicide was applied once, on August 20, the day after the greens were hollow-tine aerified and topdressed. The plots were evaluated for phytotoxicity, turf quality, and recovery from aerification on September 1.

Not surprisingly, plots treated with Trinity, Tourney, and Triton FLO exhibited significant phytotoxicity and reduced turf quality as compared to the untreated control. Banner and Bayleton had similar effects, just not as severe as the others.

What was unexpected was the effect of the DMIs on recovery from aerification, as measured by the number of aerification holes still visible on Sept 1. Plots treated with Trinity, Tourney, and Triton FLO recovered almost as quickly as the untreated plots, whereas both Bayleton and Banner dramatically slowed recovery, especially Banner.

So, the take home message is, even though Bayleton and Banner are labeled for application to bermudagrass greens, these products can have adverse affects on the turf, in this case, slower recovery from aerification. More research is needed to fully characterize the effects of the DMIs on bermudagrass greens. In the meantime, I'd recommend avoiding applications of DMI fungicides either before or after hollow-tine aerification practices.

Oh Man, the Flu Sucks....

Just a short one today guys.

Last week's diagnoses pretty much read: rapid blight, rapid blight, rapid blight from both northern and southern California. It looks like the rains have helped as we've seen almost no rapid blight in the lab this week. Dollar spot and some brown patch and large patch activity has been reported sporadically here and there.

I have heard about a number of superintendents fighting Pythium in Oregon and Washington right now. It's been really wet up there and according to Gwen Stanke at WSU "[It's the] Worst year I’ve seen in my 20 years here".

Other than that - I've been clobbered something this week. I'm hoping it's just a really bad cold and not H1N1 (since I already got my regular flu shot this year). Sometimes I think flying on airplanes is a great way to get sick.

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

Weather! What the...?

For those of you not paying attention to the weather in State College (as I am sure most of you don't), all I can say is WTH. State College received the earliest snow on record and it was not met with much happiness. For one thing, the leaves are still on all the trees and the heavy snow caused a lot of damage. The image to the right shows some of the damage that I witnessed outside the house on my way to work. In addition to this, I was without electricity for 2 days. This wouldn't have been such a problem except to keep warm, I had the gas fireplace going only to wake up in the middle of the night with the carbon monoxide detector going off. Needless to say, I had some trouble getting back to sleep that night! you can imagine there are not a lot of diseases in State College at this point, but around other parts of the Northeast golf course superintendents are preparing for snow mold applications. According to this weeks survey, superintendents are also participating in the numerous early-season purchasing programs offered by many of the manufacturers. This is one area that is gaining popularity and a few researchers are putting together programs related to the economics of turfgrass management. I have tried to do all year (with little success due to the lurkers in here), I will once again try to find out what you (our readers) are planning for next year. For those of you buying on the early-order programs, what is it that you are looking for and how do you plan your purchases for the upcoming year?

If you feel inclined to do so, feel free to leave your answers in the comments.

AND...for those of you lurking and not feeling like answering, you can check out what others are doing with some superintendent blogs that I like to read!

Fall is Finally Here!!!

Whoa, what's that stuff coming out of the sky? Ash from fires? Glassy winged sharpshooter exudate? Bird poop?

It's been so long that we've had rain in California, that many of us have forgotten what it looks like! By last count, Los Angeles got over 3 inches of rain, while San Francsico had just over 2.5 inches this week. (Photo of flooding on I-5 in Sacto, Associated Press)

With the rain, we should have gotten some significant leaching salt from greens, which is a good thing since rapid blight was just about the most common disease coming into the lab for the last 3 weeks.

The rain, cooler weather and aerfication = fall is here.

Creeping Bentgrass and Bermudagrass Fall Disease Prevention Practices
For those with creeping bentgrass greens, start thinking about preventive fungicide applications for take all patch control. Also - see Lane's prior post on preventive applications for Pythium root dysfunction here. We have not yet definitely diagnosed this disease from creeping bentgrass in California, but are highly suspicious that it's here. Along with fellow blogger Jim Kerns, we did diagnose this disease last spring from a location in eastern Washington. If you have had some unexplained spring/early summer collapse of creeping bentgrass greens; it may be worth it to have your roots examined for the presence of PRD this fall and winter, and try to integrate some control options this fall that will help with both take all and PRD.

Also - now is a good time to focus on spring dead spot control on bermudagrass. Check out Lane's recent posts on the disease here and here.

Desert Overseeding

Just ask superintendents like David Major, Gil Stiles, Paul Mayes, Willie Lopez and a host of others - if I set up a disease trial on a course, 9 of 10 times, the disease will not show up (10 of 10 times, bikini clad supermodels won't show up either). Now add Tom Shephard at Desert Falls CC to that list. No Pythium in Coachella in our trials started a few weeks ago. I just might start asking superintendents for $1000 bucks a pop to set up trials on their course next year; there'll be a 90% chance they'll have absolutely no disease while I'm there.

Although there have been just a few nights over 68F during the last two weeks in Coachella, for the most part, nights have been in the low 60s and 50s, and daytime temps below 100 (as low as the 70s recently). (Photo of Silver Rock Resort, Riverside Press Enterprise)

Although no Pythium has been reported from the desert, that doesn't mean that the overseed isn't problem free. The cool weather is certainly delaying perennial ryegrass establishment - I hope that the courses there are able to get it up before the courses are set to open. Just to warnings though, please adjust irrigation scheduling on the turf in the cooler weather to prevent other issues from arising, and try to limit play on newly emerged areas if possible. Overwatering and traffic on tender plants this year would certainly do more damage on turf than Pythium this year.

The Bacterial Wilt Mystery Continues - Is There a New Kid in Town?
A few weeks ago, there was a big scare in California regarding potential outbreaks of bacterial wilt on Poa. Although the damage we saw was definitely real, we have not been able to isolate the bacterial wilt pathogen, Xanthomonas translucens, from diagnostic samples. It could be a case of getting to the party too late, but it's hard to draw any conclusions yet based on the limited data we have. We're continuing to work with Dr. Larry Stowell on this issue.

On the other hand, working with Larry & UCR's new Plant Bacteriologist, Dr. Caroline Roper, we have been able to isolate and identify a Pantoea species of bacteria from a few of the diagnostic samples. Some Pantoea species are known to cause diseases including Stewart's Wilt of Corn and a blotch of sudangrass. We'll know in the next few weeks what role these bacteria play in the damage that was observed on a few courses this last summer.

Single No Longer!
Just in case everyone was wondering why I've been running around like a chicken without a head for the last few weeks:

I've been doing new husband-y stuff and it's great.

Thanks to everyone for all of the well-wishes!

Old Man Winter Decends on Midwest

Not much going on in the Midwest last week or this week. Temperatures are 20 to 30 F below normal and we actually had appreciable snow this past weekend!! I have to apologize for not posting last week, I was traveling to North Carolina and did not have a chance to write my post. This week will be a short post too. Not much going on with respect to diseases in the Midwest, too dang cold!

The only good day the last couple of weeks was last Monday. We had the Wisconsin Turfgrass Association Golf Outing at North Shore Country Club in Mequon, WI. The weather was fantastic and considering the economy we had a nice turnout. I believe we had 84 participants, which included myself. The proceeds from the outing go to support the Wisconsin Distinguished Graduate Research Fellowships. We have four fellowships at the University of Wisconsin-Madison- Robert Newman (Horticulture), Wayne Kussow (Soils), Jack and Flora Berbee (Plant Pathology, and the Kurth (rotating). For a state with only 5.5 million people we have a fantastic industry!

Sorry if this sounds boastful, but after last week I felt the urge to talk about our industry. Next week I plan to start a series of posts detailing the different winter diseases. The first three posts will be detailed descriptions on the three major winter diseases-gray snow mold, Microdochium patch, and snow scald.

On a final note, I would like to Congratulate Frank Wong and his wife Caroline! I wish you guys all the best!

Prevention of Pythium Root Dysfunction in Bentgrass Greens

For golf course superintendents who've struggled with Pythium root dysfunction in the past, now is the ideal time to initiate a preventive fungicide program. Pythium volutum, the most common PRD pathogen in our experience, starts to actively infect bentgrass roots in the fall when soil temperatures consistently dip below 75 degrees. That, combined with plenty of moisture throughout the Southeast, means that the pathogen is almost certainly active now.

Not very many products are effective against PRD. Even though it is caused by a Pythium, some of the standard Pythium fungicides like mefanoxam, propamocarb, ethazole, and fosetyl-Al are not very effective when applied alone.

Instead, the QoI and Qii fungicides have been most effective against PRD in our trials. The QoI fungicide Insignia (0.9 oz) has historically been the most effective product. We have also seen good control from Heritage TL (2 fl oz) and Compass (0.25 oz) but only on a preventive basis.

The QiI class of chemistry is relatively new, and there is currently only one product available in this category: Segway, which contains the active ingredient cyazofamid. Applications of this product at 0.9 fl oz per 1000 sq ft have also provided very good control of PRD. Segway is an important addition to our arsenal against PRD because it gives us another chemical class to rotate with to prevent the development of fungicide resistance in Pythium volutum.

Tank-mixtures of fosetyl-Al + propamocarb (Signature, 4 oz + Banol, 2 fl oz, for example) and fosetyl-Al + mefanoxam (Signature, 4 oz + Subdue Maxx, 1 fl oz, for example) have provided good control in our trials or based on superintendents' observations. These tank-mixtures, although expensive, should also be worked into your program to help prevent fungicide resistance.

As mentioned above, a preventive program should be initiated in the fall when soil temperatures consistently dip below 75 degrees. Repeat applications on 21 to 28 day intervals as long as soil temperatures are between 50 and 75 degrees are recommended where PRD has been a persistent problem. Less frequent applications may be sufficient where the disease has only been a minor problem or where growing/management conditions are less stressful during the summer. Since PRD is a stress-induced disease, there is no "one size fits all" fungicide program to control it.

Note that applications of Insignia and Segway should be watered into the soil immediately to drive the fungicide into the root zone. Approximately 0.125" of irrigation has worked well in our trials. Since fosetyl-Al moves downward in the plant, tank.mixtures including this product should be left to dry on the foliage for best results.

Congratulations Dr. Wong

For those of you who have been following this blog, you should be well aware of Dr. Frank Wong's humorous posts. Keeping everyone up to date on the West Coast, Frank does a great job of mixing the specifics of the disease with some local flare.

Well, Frank is getting married this weekend to a wonderful woman and I hope all of the those that find this blog useful will join me in congratulating him on him marriage to Caroline.

Frank, as always...You Da' Man!

Cooler Temps and Microdochium Patch

I waited until today to post this because I wanted to confirm the diagnosis, but Microdochium patch is now active in PA (and probably many other areas). The cool wet weather that we have had over the past few weeks has brought on a few cases of Microdochium patch on putting greens and tees.

I will refer you to Jim's post last week for more information on the disease and also to the Photo Gallery. The photo gallery is a great place to check out images from various diseases and they include both signs and symptoms of the disease.

Other than active Microdochium patch, many are in recovery mode from old dollar spot damage. Depending on your geographic location, you may even be fighting active dollar spot symptoms. Cooler temperatures, however, should mean that the end is in sight for this disease. For those in the mid-Atlantic region (Northern VA, Maryland, and the Philadelphia area), you may need to stay alert as moderate to severe dollar spot outbreaks occurred very late in the year in 2008.

The only other disease that I have seen in abundance in the field is lingering cases of rust on perennial ryegrass and Kentucky bluegrass. At one regional golf course, the roughs had been thinned out some by the disease. However, the real trouble were the complaints from the golfers about the orange "stuff" on their shoes. Had I been there to hear the complaint, my comment may have been "You're not supposed to be in the rough anyway."

Mazel tov! It’s nozzle talk!

I recently finished writing up a study about the use of different nozzle types and water rates for dollar spot in putting greens. When working on a presentation about this awhile back, I noticed that “nozzle talk” sounded like “Mazel tov!” and so that was a running joke in my house for a few days.

I worked with a colleague in our Biological and Agricultural Engineering Department, Dr. Bob Wolf. Bob has done a lot of work with nozzles and spray technology in field crops such as corn, but he also works with turf. We also had some valuable discussions with Matt Giese from Syngenta as we were selecting nozzles and working out the protocol. We did the studies in 2007 and 2008. Other researchers have examined nozzles and water volume previously, and I won’t get into that for the moment. That might be a good topic for a winter/off-season discussion. John has done a fair amount of work in this area with Mike Fidanza, for example, and others have too. I’ll just describe our KSU study. It is published in the online journal Applied Turfgrass Science.

We did the work on an A4 creeping bentgrass green that was maintained at 0.156 in. We looked at 5 nozzle types, and each nozzle was used with 0.5, 1.0, and 2.0 gal/1000. We used Daconil Ultrex at 1.8 oz/1000. This is the low rate and was used so that there was enough disease pressure to allow us to see some differences. That is, with a high rate we may not have seen enough disease to tease apart differences.

The nozzle types we used were:

*Extended range flat-fan (XR)
*Air Induction
*Turbo Twin Jet
*Turbo Drop Twin Fan

Each nozzle was used in 02, 04, and 08 flow rates to give 0.5, 1.0, or 2.0 gal/1000. The flow rate is usually printed on the nozzle (as shown in the next photo) and represents gal/minute at 40 PSI. 02 = 0.2 gal/minute for example. The Turbo Twin Jet is not available in 08 orifice size, and therefore a Turbo Duo adapted with two Turbo Twin Jet 04 nozzles (TT11004) orifices was substituted. (Basically, we used two Turbo Twin Jet 04’s stuck together).

The TurfJet nozzle produces coarse droplet sizes and usually has less complete coverage, and in some previous studies it has provided less disease control than others. The XR is commonly thought to provide very complete coverage and is widely used and thus was selected as the comparison “standard.” The Air Induction nozzle is designed for drift control. In air induction nozzles, air is drawn into the nozzle body and combined with the spray solution to form large, drift-resistant “bubbles” which explode upon contact with the plant. The Turbo Twin Jet (with a pre-orifice design to reduce drift) and TurboDrop Twin Fan (another air induction design) are recently-developed nozzles used more in field crops that have not been tested for disease control in turfgrass systems. They produce a “twin stream” of water as is shown in the photos.

In our studies, the 0.5, 1.0, and 2.0 gal/1000 water rates all performed similarly with few significant differences. That is, for most nozzles on most rating dates, all water rates performed equivalently. In addition, for the most part all the NOZZLES performed similarly except for the TurfJet nozzles which had poorer disease control on some rating dates.

The images below show how we collected some spray coverage data. Bob then scanned the water-sensitive papers and ran them through an analysis program.

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