Crown hydration, Poa seedheads, and other headaches

Here we are only a few days away from May and we are dealing with all sorts of problems in the Northeast. I just got off the phone with a superintendent in Connecticut who is dealing with some dead grass due to the crazy weather we have had. In his case, a late season freeze following some heavy rains resulted in some serious crown hydration problems. Although I don't have any photos to share (not that he would want them out there), the solution that we both agreed on was a good pummeling. His greens are nearly 100% Poa and we decided that disturbing the soil as much as possible to create a seedbed (there is probably millions of seed in his seedbank) is the best bet to get green turf as soon as possible. We are fortunate that it looks like decent temperatures for growing grass should be here for a while (unless all of the sudden it goes right to summer).

Within the last few weeks, we were also able to rate our snow mold trials. Rather than go into too much detail about this, I have posted our final report and a pdf of the individual treatment images in my dropbox file (link) . Feel free to download them, but they won't be up there forever. Instead the report will be moved to the Penn State site once we can get it uploaded. Other than recovery from the typical winter problems, I have already started hearing rumblings about the following diseases being active: anthracnose, brown ring patch, fairy ring, yellow patch (aka., cool temperature brown patch), microdochium patch, and probably others that I forgot to mention.

What most people have on their mind right now is 1) the success of the Poa seedhead programs and 2) the start if they haven't already started of the early season dollar spot treatments. Due to weather problems, we didn't get our early season trials out until yesterday, but our seedhead trials (applied at various timings between 200 and 500 GDD) have all gone out already. We are just now starting to see some seedheads, but ratings probably won't tell us much until this week or next. If you have any thoughts or input on what you are seeing or how your Poa seedhead treatments worked out for you, please pass them along in the comments or on the Turf Diseases Facebook Page.

Finally, if you were wondering about my South Africa post, I just got my computer back last week and haven't had a chance to upload my pics. I hope to get to them this week so the post can hit this weekend. Good thing that Dr. Woods gave us a great International Disease Post last weekend.

Plenty of snow mold in the Northeast

View of St. Francis Links and St. Francis Bay in South Africa

Things have been very hectic around here so I have not had much of a chance to post anything in a while. Following a week long trip to South Africa (more on this next weekend), I fired up the old (actually it is only a few months old) computer to have it completely crash on me. That was about 10 days ago and I have yet to get it back. Shouldn't there be some sort of insurance on these things for lost work time. If I were running a business and relying on a single computer (luckily I have a backup) then I would be totally screwed.

Gray snow mold pressure in 2011 fungicide trials

Anyway, since coming back I have been busy putting research protocols together and also wrapping up research studies from last year. In particular, I was able to drive up to Yahnundasis Golf Club located near Utica, NY to rate my snow mold trials from last fall. Depending on your perspective this was a great year for snow mold and disease pressure was upwards of 80% in select plots. Our data is kind of perplexing as PCNB didn't really do all that much. While some plots didn't look all that good, several treatments resulted in excellent control with some even providing 100% control. This report should be up on the Penn State website relatively soon (relative in academia means by June).

Most of us are now in recovery from any problems, but I have seen several courses this year that are greening up pretty nicely and look great. It's already turning into a strange year. We have had unseasonably cold weather with individual days of extremely warm temps. Today in State College, the weather is about 75F while tomorrow is going to peak at 51F. Despite this fluctuation, our GDD at Penn State hit 289 yesterday and probably picked up several more today. Therefore at least according to the GDD we are right in the early stages of Poa seedhead control. We have a study at the Penn State Golf Course now looking at GDD timings for various products and a new experimental product. Hopefully we can get a better handle on what works in terms of timing for our region. For some reason, the GDD timing used in Michigan as part of Ron Calhoun's program doesn't seem to work well here...at least we haven't been able to dial it in. I hope to continue to put out these trials to figure out the best timing and products for our region...any feedback that you can provide regarding what works for you would be great!  If you want to learn more about Ron's GDD Tracker site, I encourage you to visit it at www.gddtracker.net. It is a great site and a valuable resource for those in his region.

To Spray or Not to Spray

It is really nice to experience a warm-up in Mid-February, but we know that it is a likely a cruel trick from mother nature. NBC 15 in Madison just said that Monday could yield 5 to 10 inches of snow, if all the expected precipitation is snow. Yet, today temperatures exceeded 40 degrees in Southern Wisconsin and is expected to exceed 50 degrees tomorrow! Its funny that I get excited about 50 degrees, when I was in North Carolina I considered that cold. As the warm-up continues, the snow will be melting and gray snow mold and Microdochium patch may show their ugly heads. If fungicides were applied last fall, then I would not expect too much damage. However some areas south of I-80 may not have made preventative applications. I know many down in Missouri, Arkansas, and maybe even Kansas did not make preventative applications. Based on the duration of snow cover in those areas, gray snow mold will most likely not be a problem. Microdochium patch however may be a problem.

The question arises, should I spray when the snow melts? To determine if an application is warranted there are two things to consider: 1) Is the fungus causing new infections? 2) Is the ground saturated? When the snow melts Microdochium patch symptoms maybe apparent and severe, but if environmental conditions are not conducive the pathogen will not continue to spread. Microdochium patch will continue to develop when temperatures remain below 68F with high humidity, intense cloud cover, or both. Symptoms immediately after snow melt usually have the "classic look" with a pink or orange tint. An image of these symptoms are at the upper right hand side of this post. If environmental conditions are conducive for Microdochium patch development in the absence of snow, symptoms will have a water-soaked appearance with center gradually turning a light brown. An image of those symptoms are below. If there are any questions about the activity of the fungus send a sample to a diagnostic lab.

Another factor to consider is how saturated the soil is. Applications of any material to saturated ground should be avoided entirely. Failing to do so could result in loss of the material to runoff. Another consideration is running equipment over saturated ground will likely do more damage than the fungus will.

If conditions become conducive for Microdochium patch development, there are fungicides that will halt its development. Fungicides with the active ingredients iprodione, vincozolin, thiophanate methyl, trifloxystrobin, azoxystrobin, pyraclostrobin, fludioxonil, and chlorothalonil are effective against Microdochium patch. Normally it is hard to beat the dicarboximides and thiophanate methyl for Microdochium patch control, but there are other options that maybe more relevant in your area. Chlorothalonil does not perform all that well by itself, but it is a good tank mix partner with any of these other products.

On another note, after receiving much ridicule from Dr. Kennelly and the Packer Nation that surrounds me about the tragic loss the Bears were handed by the Packers, I am looking forward to baseball Spring training. Like I say every year, as all Cubs fans do, this is the year to break the Billy Goat curse!

Potassium, Hokkaido, and Snow Mold

I'm at snow-covered Hokkaido for some seminars this week and one of the things I have mentioned in the seminars is the possible increase in snow mold damage that can occur with high rates of potassium application in the fall season. Dr. Kerns mentioned the research being done at Cornell now to investigate this phenomenon.

We came across this observation on an L-93 field trial that we had designed to study soil testing methods, not snow mold. What we found, as you see below, is that plots treated with potassium in the previous year (and to which no fungicides were applied to prevent snow mold) had an increase in snow mold damage compared with plots to which no potassium had been applied in the previous year.

In both 2003 and 2004, when the snow had melted from the research green, we observed a linear increase in gray snow mold damage with increasing rates of potassium application.

Hokkaido has heavy snow mold pressure. Many of the golf courses are under snow for four months. The photo below shows the effect of fungicide application in the fall (at right) vs. no fungicide (at left) in the snow mold damage to a golf course rough at Obihiro in mid-May. Clearly, one would not want to exacerbate the disease intensity by unwarranted application of potassium.

Instrata (Chlorothalonil + Propiconazole + Fludioxonil)

Instrata is another fungicide that combines different active ingredients into a single product. Instrata has chlorothalonil (Daconil and many others), propiconazole (Banner MAXX and others) and fludioxonil (Medallion). Instrata quickly became the gold standard for snow mold control in northern climates like the Upper Midwest. Interestedly the formulation of this product combined suspended particles with a microemulsion that Syngenta calls a suspomicroemulsion. I really don't know what that means for golf course superintendents, but you have to admit it sounds cool! All kidding aside, we typically suggest that active ingredients should be mixed in order to achieve acceptable snow mold control. With Instrata you have three active ingredients that when combined do provided excellent snow mold control. Chlorothalonil is a contact fungicide that has activity on all three snow mold pathogens (Microdochium nivale, Typhula incarnata and Typhula ishikariensis), but is strongest on M. nivale and T. incarnata. Propiconazole is a DMI fungicide, which are known to have excellent activity on T. ishikariensis and fludioxonil seems to have activity on all three snow mold pathogens too.

For those who manage golf courses in areas that receive intense snow cover will likely experience all three snow mold pathogens at one time or another. I think the reason Instrata is a successful fungicide for snow mold control is golf course superintendents don't have to worry about predicting the weather because all the product works on all three snow mold pathogens. With respect to efficacy of Instrata, I have posted a few figures highlighting how well this product works. We do see breakthrough at our site in the UP, which has intense snow mold pressure. Yet, for the last two years we observed that 70 % of the products break down under that pressure. Even under that pressure, a single application of Instrata keeps disease severity levels between 15 and 40 %. Anyone that experiences such snow mold pressure should make two applications for snow mold and we observed that two applications of Instrata at 5.5 oz worked better than a single late application of Instrata at 11 oz at our UP site. For most golf course superintendents however, the 9.3 oz rate will work beautifully! A word of caution about the product, do not skimp on the rate in areas of high snow mold pressure. We have observed that reducing the rate to 5.5 oz in some environments may result in significant failure.

In summary, Instrata is an excellent combination fungicide for controlling snow mold diseases. It also has activity on other diseases too, which is obvious based on the active ingredients in the product. Instrata is an excellent choice for putting greens and tees and if the budget allows high value approaches and maybe even fairways. If you are interested in this product and have not used it before check out the label and Syngenta's website for more information.

Things to Consider Post PCNB Stop Sale Order

Hello again, its been a few weeks since I have posted anything. Except for the news about PCNB, the fall has been exceptional in the Midwest. Temperatures have been very conducive for golf, almost too conducive. I wonder if those who lost turf this summer had any difficulty recovering because of too much traffic during the fall season. Samples completely halted at the Turfgrass Diagnostic Lab around October 1st, mainly because we were fairly dry. The only disease that proliferated during the fall was rust, even some golf course superintendents called about massive amounts of rust in the roughs.

For those that had to select an alternative to PCNB there are a few things to consider for next year. First, one of the beauties of PCNB was its long residual control of Microdochium patch. Thus if Microdochium patch is observed after melt, than a follow-up fungicide application maybe warranted. Our research has shown that the fungicides iprodione and chlorothalonil only provide about 30 to 40 days of Microdochium patch control under winter conditions. Interesting enough we did not see extended control when comparing plots covered in snow versus those plots that were kept uncovered. The image above shows the length of control we observed with chlorothalonil. In other words, do not blame your snow mold fungicide mixture if new Microdochium patch infection centers develop during the spring immediately following melt.

The other thing to keep in mind is the issue with PCNB has not been resolved, at least not to my knowledge. Basically it would be wise to think about budgeting for snow mold without using PCNB as an option. That way you are prepared if the stop sale is not lifted. There are a number of options that I have already covered in previous posts, but feel free to contact us if you want to discuss other options for next year.

Most of the bloggers attended in the Agronomy meetings in Long Beach, California last week. I love these meetings because of the breadth of information presented. One of my favorite talks from the meetings, besides my own students', was given by one of Dr. Frank Rossi's students David Moody. He has determined that potassium applications in the fall may make turf more susceptible to snow mold damage. They established a very elaborate growth chamber experiment to test this hypothesis, but they stumbled upon this observed causally in the field. Basically they think the excess potassium stimulates the plant to shuttle potassium, citrate and malate into the vacuole in order to maintain osmotic potential. In turn this shift in osmotic potential slows down the production of carbon skeletons and energy, which are essential to plant defense. I believe this was the first or second year of David's research and I will be interested to follow his results and progress.

One of the highlights of the meeting was an outside meeting to discuss a proposal for a Multi-State Regional Project on Dollar spot research. This is a formal process that will allow all those who participate to meet once a year to discuss dollar spot research. Originally this idea was spearheaded by Dr. Mike Boehm at Ohio State University, but the reins was passed to Lane upon Dr. Boehm's promotion into upper administration at Ohio State. The beauty of this meeting was hearing what everyone was doing and realizing that very few turf programs overlap with respect to dollar spot research. This project has a five year term, so maybe in five years we will have a better handle on the biology of dollar spot!

Stay tuned next week as we start a series of discussions on the newer fungicides released in the past couple years!

Cool Temperatures Bring a Sigh of Relief!

Temperatures in the Midwest are finally cooling down. This week has been a godsend as I heard from a superintendent this afternoon. Yes temperatures are going to rise again this weekend, but the nighttime temperatures are supposed to remain below 70 degrees. I agree with John that this is the time to start overseeding, fertilizing and maybe even aerifying to bring the greens back to life before winter. However, I do not think this is the time to start bringing the mowing heights back down and starting on paclobutrazol programs. I tend to be very conservative and I think this week is an ideal time to allow the plant to grow under the least stress possible.

This week’s cooler, dry weather has shut down most of the diseases we have dealt with this summer. I don't know this for certain for every location in the Midwest, but I do know that my phone was very quiet the last few days. We still are getting samples of Poa annua crapping out either from heat stress or summer patch or a combination of both. This was an exceptionally difficult summer for golf course superintendents. Most the turf loss this year was due to heavy rains in June and July coupled with high day and nighttime temperatures. Soil temperatures in many locations I visited exceeded 95F, which is not a good growing environment for any cool-season grass to say the least.

The major lesson I learned this summer was the importance of establishing a written set of maintenance and playability standards. By putting categories like day-to-day green speed, firm, fast or green, lush gives the golf course superintendent a lot of flexibility. For example, a hypothetical course has established a maintenance standard of 9 foot green speeds every day. By simply stating this standard allows the golf course superintendent to vary practices to achieve this ball speed. Viable options would be alternating mowing and rolling, switching to smooth rollers, and raising the mowing height in an attempt to minimize turf loss. I do understand that setting maintenance standards may not work for each situation, but it may be something to try especially at a public play facility. You may think I am crazy for talking about this, but based on my observations this summer establishing a set of maintenance standards seemed to work.

This is also the time to start thinking about snow mold applications. Here is a link for our snow mold trials for 2009-2010. The key with these reports is to look at the treatments that provided the best control (lowest disease severity) at the site closest to your site. We test a wide variety of chemicals and combinations at five locations in order to provide golf course superintendents with a plethora of options. We do not distill the reports down to the top ten best products because the best products and combinations may not be within the budget of many golf courses. So we always recommend finding the product or products that provide the best control and fit within the constraints of your budget.



Timing of snow mold fungicides was a fairly hot issue early this spring, largely due to some perceived failures of very good snow mold fungicides. We still do not have a great answer, so are initiating a fairly large fungicide timing experiment this fall. We expect to see good control from systemic products when they are applied well before snow cover, and good control from contacts closer to snow cover. We will let you know next spring, so stay tuned.

Snow Mold Rating Season Has Begun!!

Whoopee! Snow mold rating season is in high gear for us. The first site we visited last week did not have a lot of activity, but our site in Stevens Point, WI was fantastic! The non-treated controls averaged 90% disease and a few products had some break through. For the most part however, most treatments did a good job preventing snow mold. We have not had a chance to enter the data and analyze it, but mixtures did exceptionally well. Products like Instrata at 9.3 oz, mixtures of Trinity/Insignia/Iprodione, Interface/PCNB, Chlorothalonil/Myclobutanil/Iprodione were just a few examples that performed exceptionally well. Interface is a new product from Bayer that will hit the marketplace some time this summer. Typically most products do well at our site in Stevens Point WI, but some of the excellent products and mixtures break down under the intense snow mold pressure at our site in Marquette, MI. We really do not know what to expect at our sites in Minnesota this year. I think both sites had substantial snow fall and cover, but one site is new and snow mold development at the other site is variable.



We do exhaustive testing of products for snow mold control and the main lesson is to combine fungicide families to achieve excellent results. Using just a single product with a single active ingredient is asking for break through. At least that is the case in the Upper Midwest. We do not have a single answer for what to apply for snow mold control because it depends on the pathogen normally observed, the courses budget and the threshold for damage. Since we do not have crystal balls to forecast the amount of snow during the winter months, combining active ingredients will ensure protection against Microdochium nivale and the two Typhula species. Combining a.i.'s usually works very well in our trials, especially those combos that are strong on ascomycetes and basidiomycetes. Pre-mixed products like Instrata and Interface usually accomplish this strategy. Chlorothalonil, propiconazole and fludioxonil are the a.i.'s in Instrata and Interface is a mixture of iprodione and trifloxystrobin, both mixtures have good activity on snow mold fungi. Pre-mixed products are not necessarily the best and golf course superintendents can develop their own mixtures. We have last year's snow mold data posted on the Turfgrass Diagnostic Lab's website, but if you are interested please check back in a couple weeks to see this year's data! For those in the Upper Midwest, we will be conducting Snow Mold Field days on April 14th (Minnesota??), 15th (Stevens Point, WI) and 16th (Marquette, MI). Please contact me (jkerns@wisc.edu) if you would like to attend. We do not charge for the events and we will have the specifics after next week. Stay tuned for photos from our more northern sites next week.

Cold and wet and that damn groundhog

Well, I guess we can "officially" [I just jinxed us] say that winter is over. That damn groundhog in Punxatawney, Pennsylvania screwed us again with the extended winter and my wife even suggested that she may be willing to have someone "take him out" next year. Regardless of whether you enjoyed this snow-filled winter or not, the bottom line is that spring is quickly approaching and it is now time to start planning your disease management programs.

Based on Frank's post last week, I would expect that brown ring patch is just around the corner for turfgrass managers in the Northeast (although some in the mid-Atlantic may be a little ahead and already seeing symptoms).  The biggest thing I have been seeing is cool temperature brown patch and gray snow mold.  With the cold, wet weather throughout much of the Northeast, golf course superintendents should make sure that they are identifying the type of snow mold on their property.  While much of what I have seen in the field looks a lot like pink snow mold, we have actually diagnosed it as gray snow mold.  More specifically, we have identified it as Typhula incarnata based on the orange sclerotia and presence of clamp connections on the hyphae.  While you can't see the clamp connections without a microscope, you can easily identify the sclerotia without the aid of a lens [or if you have poor eye sight, you may need a low powered loop].  If you are dealing with gray snow mold, there is not much that needs to be done in the form of fungicides.  The damage is done and you should now be in recovery mode.

(Above) Sclerotia of Typhula incarnata within creeping bentgrass.

On the other hand, if you do not see sclerotia within these infested areas it is likely that you are dealing with pink snow mold (Microdochium patch).  This may end up being a big problem in the coming weeks as the turf is likely saturated from all of the melting snow and the large storm that has battered the Northeast over the past few days.  In situations where you haven't quite fired up the sprayer or where the greens are just too wet to get on right now, the disease may continue to spread and cause significant damage.  If this is the case, you may consider pulling out the sprayhawk to treat greens with minimal disturbance.

In addition to your planning, the authors here at Turf Diseases have also been doing a little preparation to better serve you as we enter the disease season.  This past week, we launched the Turf Diseases Fanpage on Facebook.  I have to admit, I have been pretty much out of the FB loop and more consumed with the blogs and twitter, but in our first week on FB we had over 350 new fans.  I guess that the blog and twitter still aren't mainstream enough for you so I am glad we added the function.  I hope that everyone will take advantage of the interactivity of the site and contribute.  A brief shout out should be given to Chris Tritabaugh of Northland Country Club for posting the first fan photo (gray snow mold) and to Keith Angilly, Frank Tichenor, and Peter Rappoccio for giving me some insight into what is going on in Connecticut and New Jersey.  Peter and Keith even got into a little discussion about the efficacy of Civatas, which seems to be a popular topic on these threads and it is gaining a lot of attention with only limited information available.

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A New Season Approaches

Hello again! I know my posts have been few and far between this winter, but now the snow has started to melt! I returned home this evening from pesticide applicator training in Eau Claire and Green Bay, WI and was excited to see my front yard again. I was also excited to see that my yard was free of snow mold damage, whoohoo! That being said our snow mold rating season is about to begin. We will likely head over to Milwaukee and Stevens Point, WI next week to do our first ratings. Most places in the Upper Midwest have had at least 6o days of continual snow cover, which is ideal for gray snow mold development. In Madison we have not seen bare ground since December 9th, so I suspect we will likely see substantial snow mold problems as far south as Chicago.

I have not experienced the travel problem that my fellow bloggers have. The only struggle I had was getting out of Oklahoma in January. A massive snow storm blew through Oklahoma and airlines were proactively cancelling flights. I had to be home that weekend because my wife had plans for my birthday, so I drove from Stillwater, OK to Madison. It was about a 12 hour drive and for the most part was quite pleasant.

The major change this year in Wisconsin is the statewide phosphorus ban in turf and landscape fertilizers goes into effect. Specifically the ban will take effect April 1, 2010. There are some exceptions to the regulation and they can be found on the following website: http://www.datcp.state.wi.us/arm/agriculture/pest-fert/turf_fertilizer/index.jsp. Basically, starter fertilizers are allowed during new establishments or if soil tests show that phosphorus is deficient. If you have any questions about this regulation please consult the website above. It does a nice job explaining the exceptions.

On a completely unrelated note, our department is celebrating is Centennial this summer. Here is the website: http://centennial.plantpath.wisc.edu/ and it has some interesting articles from Arthur Kelman, J.C. Walker and Glenn Pound about the future and direction of plant pathology and the role of extension specialists in education. A nice program has been organized for June 24-26th and you are an alumni we hope you can make the celebration!

Now that the snow is finally melting, I will start posting on a regular schedule and if all goes well I will have some nice snow mold pictures soon. In the meantime hope you enjoy the Statue of Liberty on Lake Mendota, who knew they loaned out her head :).

Great conference, but a tough spot to watch hockey.

 

(Above) The crowd in Toronto reacts to the OT goal that sealed

the win and a gold medal for Canada...and a silver for the USA team.

This past week was spent at the Canadian International Turfgrass Conference and Trade Show and the New England Regional Conference and Trade Show.  Both were great shows and I had a chance to discuss some disease issues facing both groups. In Canada, the buzz was around the relatively new cosmetic pesticide ban.  This seems to be the first step in eliminating pesticides from turfgrass management.  While golf courses are currently exempt from the ban, many of the areas on the property are not exempt.  This includes such areas as the entrance ways to the facility as well as the turf grown around the clubhouse and other areas not directly related to the game of golf.  You can definitely expect a decline in turf quality in these areas.

More important than the areas around the clubhouse, however, is the ban on pesticides for athletic fields.  The inability to suppress weed species and other pests such as diseases and insects will likely start to appear.  Unfortunately, this will likely occur in the form of childhood injuries and other accidents due to poor playing conditions.  In a brief conversation with Dr. Vittum from UMASS, she expressed that in her role as a referee that she has had to cancel games in New England due to the potential for injury and her personal liability as the referee.  While this is an extreme case, these issues could become more prevalent in Canada due to this ban.

After leaving Toronto with my head hanging low due to the USA loss against the Canadians in the hockey finals, I headed to Providence where the NE1025 group was wrapping up its final meeting to discuss the progress with managing anthracnose basal rot and annual bluegrass weevils.  As part of the reports from each participant, we were fortunate enough to have Stan Zontek, Director of the mid-Atlantic Green Section, provide an update on his perspective of anthracnose in his region.  Here is Mr. Zontek's statement:

"Prior to this research initiative, anthracnose was one of the most common and devastating problem to golf course putting greens in those parts of the USA where Poa annua (annual bluegrass) is the predominant grass species on putting greens.  This research information, supported by field observations, established the fact that this disease was made worse by (1) the species of grass, (2) close mowing (in the quest for faster green speeds), (3) reduced fertilizer inputs (another factor for producing faster green speeds), and anecdotal observations that anthracnose was made worse by (4) frequent, light topdressings, vertical mowings, heavy foot and equipment traffic (including rolling) and the associated care a putting green receives to achieve fast green speeds.  Golf course putting greens were declining due to anthracnose in spite of the increased usage of fungicides.  In fact, fungicides were routinely applied every 5-7 days to greens with limited success in controlling anthracnose.

The research results from the NE-1025 group have shown that anthracnose can be prevented through higher annual rates of nitrogen.  The healthier the grass, the less prone it is to anthracnose and, significantly, the need for fungicides is greatly reduced.  The reduced usage of pesticides is definitely a positive result from this research. 

It has also been shown that mechanical operations like light topdressing, vertical mowing, rollings and even foot traffic are less of a problem than once thought.  When you couple these shifts in how the turf is managed, the maintenance of putting green speed can be achieved via the use of plant growth regulators (PGRs), the judicious use of putting green rolling and double cutting including the maintenance if not increase in mowing heights. 

The benefits of Poa annua seedhead suppression were also studied.  This too contributes to healthier turf, less anthracnose and better overall putting green quality during those periods of the year when seedheads are produced. 

To golf course superintendents in the field, the research results from all the anthracnose studies have provided a far better knowledge base than before this work was begun.  The results have been embraced by our industry to a point where anthracnose, which was formerly a huge problem on putting greens, has now become a minor problem to even being, non-existent.  These are spectacular results."

- Stan Zontek, USGA

(Above) Sclerotia within infested tissue can help you distinguish Gray Snow Mold from other snow molds.

All in all, these were informative meetings and the conference season is just about wrapping up.  Updates from around the region suggest that the snow is finally starting to melt and with that snow molds appear to be the largest problem.  Specifically, areas that often are damaged by Microdochium patch (e.g., Pink Snow Mold) are instead showing the symptoms of gray snow mold (Typhula spp.) due to the extended snow cover. It is important to check the infested tissue with a hand lens to look for the sclerotia embedded in the tissues because fungicide applications for gray snow mold are not necessary at this time.  If you are dealing with Microdochium patch, however, it may be important to continue to monitor the situation as fungicide treatments may continue to be necessary depending on the pending weather conditions.

Interesting Winter Disease in the Midwest

Happy belated New Year to everyone! I wanted to thank John for the wonderful birthday post! What a great photo and yes it has been cold enough here to warrant hair on every millimeter of skin! Although the winter in the Midwest has not been as abnormally cold when compared to other parts of the country, we have had some extended periods of extreme cold and snow cover since December 9th. South of I-80 there is not as much snow on ground as areas north of I-80. So there is not a lot to talk about in the Upper Midwest, except that ice damage could likely be an issue this year. Why? We haven't completely lost snow cover, but we have had some melting that has probably lead to ice formation underneath the snow. So you may want to keep an eye on areas that are prone to ice damage.

Besides letting everyone know that I am still alive, I wanted to post something that I thought was pretty unusual. Dr. Derek Settle with CDGA sent me the image attached to this post. The symptoms were necrosis of the leaf tissue atypical of gray snow mold or Microdochium patch plant and stand symptoms. Dr. Settle examined the affected leaf tissue and surprisingly found a bunch of oospores in the mesophyll cells (sexual spores of Pythium species). Dr. Settle then successfully isolated Pythium out of the affected tissue and sent the isolates to me for identification. I just got the isolates last week and I have not identified them yet, but I do know that it is a Pythium species.

I would be lying if I said I wasn't skeptical of Dr. Settle's diagnosis. I was not a believer in cool-season Pythium diseases in turfgrass, but it appears I have seen light!

I wanted to post an update on some of research that Paul Koch is conducting, but we have not analyzed the new data yet. I will post the most up to date results on fungicide degradation during winter months next week or the following week.

snow molds

First, my hypothesis is that the guy in Frank's post has chilling injury in his pants, not gray snow mold.

But, speaking of snow molds, we are starting to see some in this part of the world. We had an extended snow-cover that started in early Dec and as it has melted over the last 2-3 weeks pockets of snow mold have become apparent. I've been hearing about snow molds in golf courses but also in home lawns (particularly in low-maintenance lawns where the turf was very long and flopped over/matted down over the winter).

Since I have not received samples, I can't say for sure, but I suspect most of them are Microdochium (pink snow mold) since our snow-cover was probably not long enough for Typhula. And, even the pink snow mold is most prevalent on areas where the snow piled up extra deep, or in shady sites where melting was delayed.

John mentioned conferences, and though I am not the international-pathologist-of-mystery that he is, I did have the opportunity to participate in Nebraska's turf conference about two weeks ago. I talked about some of the work we've done at K-State with nozzles and dollar spot control.

While there I had some good conversations with Roch Gaussoin from U of Nebraska and Ty McClellan from the USGA. Ty and I have been playing tag to a number of turf conferences over the past few months--I've been running into him all over. Then, I also had a chance to meet my new turf neighbor Zac Reicher who is transitioning from Purdue over to the Cornhusker state.

And speaking of conferences, it is hard to believe that the GIS is coming up in just over a week. I'll be co-teaching a class with Frank and our colleague Phil Harmon on Monday. On Tuesday I'll be lending a hand at the "microscope class". I heard a rumor that Kaminski will be assisting in the microscope class too, but luckily my job description does not include keeping him in line :)

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!

Jim

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.

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!

What to Do About Snow Mold?

Although the temperatures are on the rise in the Midwest, a couple of superintendents have asked me about snow mold fungicides. So I thought this would be a good time to give a brief synopsis of our snow mold research from 2008 through 2009. Here is the link for our full snow mold reports, where you can view all of the treatments we tested: http://www.plantpath.wisc.edu/tdl/pdf/uwsnowmoldreports2009.pdf. First you need to know where you stand in relation to the map on the upper right hand corner of this post. If you are above the line than you need to consult the report for Wawonowin CC in Champion, MI. If you are below the line than you should consult the report from Sentryworld Golf Course in Stevens Point, WI.

Conditions at Sentryworld Golf Course in Stevens Point, WI were approximately 100 days of continual snow cover. Early applications were applied on October 21, 2008 and late applications were applied on Nov. 25, 2008. Many treatments were highly effective at this site, so please consult the report to see each treatment in detail. Some of the best performing treatments that were only applied late were Trinity (1 fl oz), Trinity (1 fl oz)/Iprodione Pro (4 fl oz), Triton Flo (0.85 fl oz)/Compass (0.25 oz)/Daconil Ultrex (5 oz), Instrata (9.3 fl oz), Quali-Pro TM/C (6oz)/QP Iprodione (4 fl oz)/QP Propiconazole (2 fl oz), 26/36 (4 fl oz)/Endorse (4 oz) and Chipco 26GT (4 fl oz)/Daconil WeatherStik (5 fl oz). Slashes represent tank mixtures and all rates are per 1000 sq ft. By no means is this list all inclusive, so please do check out the full report.



The dominant disease was gray snow mold, but Microdochium patch was observed at this site. If Microdochium patch (pink snow mold, Fusarium patch) is the dominant winter disease you face, typically an application of propiconazole or iprodione tank mixed with chlorothalonil will provide acceptable control.

The conditions at Wawonowin CC were much more severe than the conditions in Stevens Point, WI. There was continuous snow cover on the plots for approximately 170 days. The pressure was so extreme that most of the treatments that were effective in Stevens Point failed. The dominant snow mold pathogen was Typula ishikariensis, yet Microdochium patch was observed at this location. Early treatments were applied on October 2, 2008 and late treatments were applied on October 28, 2008. The only treatments that provided complete control of snow mold at this site were, an experimental from Bayer tank mixed with Triton Flo (treatment 29), 26/36 tank mixed with an experimental from Cleary's (treatment 61) and 26/36/Endorse/CX-28. However a few treatments did provide acceptable control (< 5% disease severity), please consult the reports for more specific information on these treatments.



Again this list is not all inclusive as there were some other treatments that did provide acceptable control. Application timing for snow mold fungicides is critical. It is not necessary to wait until the snow is falling to apply fungicides targeting snow mold. An old adage from one of my predecessors, Dr. Gail Worf, is spot on! Before deer season (rifle) starts in Wisconsin, which is the weekend before Thanksgiving approximately, snow mold applications should be down! Especially for those in areas that receive more than 100 days of continual snow cover. Basically you can use the reports to find a fungicide or fungicides that fit for your courses budget and situation.

Presentely the weather has warmed up in the Mid-West and dollar spot has started to surge. Brown patch is kicking back into gear and anthracnose has finally developed in a few places. It appears that the weekend is going to be warm, but not very humid so brown patch may not linger for very long. The Turfgrass Diagnostic Lab has been fairly slow the last month or so because of the extremely cool July we experienced.

Gray Snow Mold