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Spring has Sprung!

Well it looks like ol' Jack Frost is slowly shedding his coat in favor of a pair of shades and t-shirts. Spring has been slow in coming, but with 80's on the horizon in the next couple of days it looks like everything is off to the races here. From a disease/stress perspective what does that mean to you in the Southeast? Well, for the warm-season grasses (like bermuda), we should be able to start seeing how bad the winter actually was by starting to see some greening up of the tissue.

Now is the time to start looking at the stolons and stems, to see if color is returning like you see in the image to the right. If the tissue seems dead and brown, it might be time to think about ordering up some sod and/or sprigs. Another disease issue that will start be the impact the winter had on the development of spring dead spot. In Tennessee, we haven't greened up enough yet to see the circular symptoms of the disease (see left image), but with the warm weather that is ahead, it is only a matter of time.
Finally, for those of you managing zoysiagrass, large patch (see image below), caused by Rhizoctonia, will begin to rear its ugly head again. This disease can also attack bermudagrass, but the damage is not usually severe enough to warrant fungicide application (see image far below- that's a large patch!) credit: Adam Nichols, Virginia Tech)
The question of how effective spring applications of fungicides are for large patch is a good one. I don't think we have enough data to conclusively answer the question. Hopefully, you made a few applications in the fall, as that is the best time to apply preventatively.However, if you have an outbreak of large patch that is actively growing, fungicide applications might be warranted to at least reduce the spread of the disease.
Our junior-year turfgrass students are setting off on their internships for the summer, so I will be posting much more frequently now that teaching is on hiatus for awhile. So I am off to start looking for large patch in my trials, but the difference is I get excited when I have a bunch of it, and it is uniformly distributed over my plots!
Stay tuned for the next couple of weeks as we look at what spring has for cool-season diseases/stresses next week, and the following week, what we need to start thinking about for summer (which will be here before we know it!).

Elite 8!

Not much turf on the brain. We are WAY too distracted by basketball here at K-State this week. The whole town stayed up late last night watching the game go into double (!) overtime.

One of my colleagues showed a photo from the last KU vs K-State game where some KU fans held up a sign that said:

“Dear K-State,

Can we borrow your trophy case? Ours is full.

Love, Kansas

Now, apparently there is a message going around that says:

“Dear Kansas,

How is the weather back in Kansas? It is great here in Salt Lake City.

Love, K-State

I'll talk about turf again once this is all over :)

Hanging with Dr. D at University of Maryland

Hanging with Drs. Pete Dernoden and Mike Fidanza at Univ. of Maryland

Ok - I should have posted this yesterday - but I hope Dr. K (Megan) will again forgive my trespasses!

Rhizocs Active in the West
Spring has definitely sprung in the West with temps in the 60s-70s most of this week and lots of sun. Annual bluegrass greens are probably loving this weather, which is great since spring aerification and core cultivation has already started for a number of superintendents through out California and the neighboring states.

One disease that seems to be pretty active right now is Rhizoctonia Large Patch on bermudagrass and kikuyugrass.

(photo of Large Patch on hybrid bermudagrass from Craig Kimmel at Red Hills Country Club in Rancho Cucamonga, CA)

Typically a curative application of most Rhizoctonia-active fungicides will stop this fungus (i.e. ProStar, 26GT, 3336, Endorse, Medallion, etc.), but if you allow the fungus to rot the stolons significantly, you may have to wait for a long time to get adequate regrowth from the remaining plants. If the weather gets really cool continuously(<60-65f), it may take a while for the turf to grow back from the damage. In any case - it's best to treat early on high visibility areas or high traffic areas on the course, or wait until it's warm and sunny for the disease gradually disappear.

Turfgrass in Terrapin Territory

Yesterday, I had the chance to finally visit the College Park campus of the Univerity of Maryland. Maryland alum Mike Fidanza (Penn State Univ.) took me for a visit to see his old stomping grounds and to see the man, the myth, the legend, Dr. Pete Dernoden.

A tour of the Paint Branch Turfgrass Research and Education Facility was very impressive although diseases had yet to start on Dr. D's field plots.

I even got to see the wall of fame at the station with bricks inscribed with the names of supporters who helped fund the new construction of the research center. But "Where's Kaminski's brick?" I asked....

Apparently, according to anonymous resources, John got a brick engraved with all of the names of his female fan club friends, but it was so big that it wouldn't fit on the wall.

OK - that's it for this week!

Signing off from the Right Coast....

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 ( 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.

Microdochium patch kicking in

Walking around the Valentine Research Facility this morning brought some new disease activity to my attention.  Despite the unseasonably warm weather we had this past week, the slight change in temperatures and moisture finally kicked Microdochium patch into gear on our putting greens.  Although most of the damage that we had noticed prior was caused by gray snow mold, this was brand new activity.  Actually, when I first looked at the symptoms it reminded me of some type of hydraulic or fuel spill.  It was fairly scattered and not too severe at this point, but microscopic examination confirmed the condia (spores) of Microdochium nivale.  I assume that the wet, weather we are scheduled to get over the next two days (combined with more typical temperatures for the mid-Atlantic and Northeastern US) will bring some moderate cases of the disease.  There are probably a lot of fungicides that can control the disease, but it seems that most are utilizing tank-mixtures of chlorothalonil + iprodione as their drug of choice.

In addition to the Microdochium, we have seen select cases of cool temperature brown patch and brown ring patch.  As we have stated in previous posts, identification can be made by incubating a sample in a ziplock bag or tupperware container with a moist paper towel.  If mycelium is present in the morning, you are likely dealing with brown ring patch.  It seems a little early for BRP in most parts of the NE, but with the weather being so screwed up for the last week anything is possible.

Aside from the disease front, many of you may have read the facebook post about annual bluegrass weevils.  According to the USGA agronomists in the Northeast, adult annual bluegrass weevils are already on the move and have been captured in pitfall traps on a golf course in Fairfield, CT.  This is once again early for the little buggers and superintendents would be wise to keep a close eye on this if you have 1) high populations of annual bluegrass and 2) have had a history of ABW damage in the past.  For those of you not dealing with this insect, take it from many of the golf course superintendents in the Hartford region...they are a pain in the rear and resistance problems showing up in the last 4-5 years have made their management even more difficult.

Aside from the bugs and the fungi, now is also the time to start planning for your annual bluegrass seedhead control.  Depending on your choice of PGR (Embark or Primo/Proxy), you will be targeting the seedheads soon.  These control measures are often hit or miss and can vary significantly depending on the location on the course.  As you know, many superintendents base their application timing on cumulative degree days.  Although I still don't think these are great models, they can assist in determining approximate timings.  For everyone in the NE, you can check out Cornell's Forecast site for an update on cumulative degree days.

more on phos bans

Mmm, phosphoro-licious. Just when you thought you'd had enough.

A loyal fan directed me to some further information. Lest I forget, I'll go ahead and include it here now. It's a nice distraction from statistics I should be running this afternoon.

For those of you interested in more details on the Minnesota situation, the MN dept of ag has a website with some follow-up information.

There is a 3-page summary and a 41-page summary from March 17, 2007. The links are right there on the above webpage, at the top, if you want to check them out. I read the 3-pager and scanned briefly a few parts of the 41.

In the 41-pager the summary of water quality testing is on p 15-16. At the time of the report, they had not detected any trends. The "total phosphorus runoff" measured in lbs/acre/inch of runoff was about the same in 2006 as in 1999, for example, and the report contains more details about how the measurements were done, where variation can come from, etc.

On page 12-13 there are some graphs showing changes in fertilizer use.

On p. 22 they discuss how if turf stands become too sparse, increased erosion and runoff can occur.

They also have info on consumer behavior and knowledge (more for home lawn types of stuff).

Test your soil, or it's an overhead gutwrench backbreaker for you!

Image from:


You are probably wondering about Jesse the Body. We'll get to that in just a minute...

Here in Kansas our first day of spring might be marked by some snowfall. Yesterday, I went for a nice bike ride on a sunny evening wearing shorts for almost the first time this year. Tonight and tomorrow I may be getting the boots out again.

Jim mentioned the upcoming phosphorus ban in Wisconsin. It will be interesting to hear how that all goes down.

A few days ago, I happened to read an article in Golf Course Management that describes the Minnesota phosphorus ban that has been in place since Jan 1 2005, so I thought I would discuss that one too. Minnesota was the first state to pass a phosphorus ban.

The law was signed into place in 2002, by none other than Governor Jesse Ventura. [I was still living in my homestate of Wisconsin back when Jesse was elected in 1998. We cheeseheads were pretty surprised to see our normally calm neighbors to the northwest elect such an interesting character and thought maybe they all ate a bad batch of lutefisk that affected their judgment. Of course, in Wisconsin, they'd probably elect a beer as governor if there was a way to get one on the ballot].

But, back to the phosphorus ban. I’m simply going to summarize some things from this article—not get into wider issues of runoff. Fertility and runoff is not my area, but I found the article interesting. It describes the history leading to the ban, and a few comments on how it works. The article in GCM was written by Brian Horgan, Dept of Horticultural Science, and Carl Rosen, Dept of Soil, Water, and Climate, from the U of Minnesota. As part of the article, they describe how P cycles through an ecosystem, and they point out and cite some research that shows that a healthy stand of turf is excellent at controlling soil erosion, (denser stand = less runoff) and that P is most likely to runoff when there is a high soil test of P or when the P has been very recently applied.

As the “Land of 10,000 Lakes” Minnesota had been talking about nutrient runoff for awhile because of concerns about lake health.

In the 70’s, MN researchers found that P from decaying leaf litter had a larger effect on P runoff than did fertilizer that contained P. So, street sweeping was initiated in Minneapolis. Around the same time, it was determined that 70-80% of lawn and garden soil samples submitted to the U of Minnesota had a very high range of P.

In another survey of soil tests from the Minneapolis-St. Paul metro area from 1991-1994, it was determined again that 70-80% of lawns and gardens had a “very high” level of P.

So, in 2002, the twin cities adopted ordinances to limit the use of P in turf, and some other cities in Minnesota joined in. Then, as mentioned above, our friend Jesse signed the statewide law in 2002.

What does the law say?

P cannot be applied to turfgrass unless: (as stated directly from the article)

1) Turfgrass is in the first year of establishment via seed or sod; OR
2) A soil test or tissue test shows a need for phosphorus; OR
3) Phosphorus is applied to a golf course by a person trained in a program approved by the Minnsota Department of Agriculture

Golf courses were the only exemption. That is, other commercially-managed turf (athletic fields, etc) required the usual soil testing procedure.

What is the training? It is a four-hour core training with some follow up recertification based on correspondence on educational materials in their superintendent association newsletter. So far, >500 people have participated (for reference, there are ~450 golf courses in Minnesota). The U of M, the Minnesota Dept of Ag, and a committee from the Minnesota Golf Course Superintendent’s Association worked together to develop it. If you want to find out more about how the training works, check out:

What has happened?

As some of the benefits, the authors note that there is much greater availability of P-free fertilizers, which were not easy to find previously especially for homeowners. But, one of the largest benefits was the better relationship between the Minnesota GCSA and the legislature and regulators. The authors suggest that the turf industry to be proactive and get involved at the starting line when it comes to regulations rather than just waiting for it to happen.

If you want the whole scoop, be sure to check out the original article in GCM

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.

Click below to become a fan of Turf Diseases on Facebook!

spring is in the air

The cool-season turf is slowly starting to green up, buds are open on the silver maples, and I even have some crocus blooms in the garden at home.

A superintendent in the southern part of the state called the other day and said, "My greens are just starting to green up, but there are dark greens rings everywhere? What is this?" It sounded like some early-season fairy ring that I saw at our research facility last year:
Once the surrounding turf greened up, especially with the help of some spring fertility, the rings disappeared and were never heard from again. That is, they did not come back during the heat/stress period in mid-summer when we most typically see fairy ring.

Other than our occurrence on campus, and the one phone call this year, I don't have much experience with this late winter/early spring phenomenon so if any of the other bloggers, or any of you out there, have further comments please chime in.

On another note, I was reading an article the other day about green speeds/ball roll distance. Green speed and ball roll are obviously associated with mowing height, and low-mow is associated with susceptibility to some diseases, like anthracnose. So, I was curious. I'll summarize some points I found interesting:

Researchers at the U of Connecticut completed a study to investigate two questions:

1) Is there a relationship between golfer’s ranking of green speed and USGA speed categories (measured with a Stimpmeter)?

2) What is the level of golfer satisfaction across a wide range of green speeds (ball roll distances)?

They conducted their work at 29 golf courses in Connecticut, and 448 golfers participated in the survey.

A few findings taken from the authors’ summaries and conclusions:

*There was no significant relationship between golfer rankings of green speed and USGA speed categories determined by the Stimpmeter

*Golfers with a low handicap were only slightly more capable of accurately detecting variations in green speeds compared to golfers with a higher or no handicap

*No matter the actual ball-roll distance, 87.5% of golfers rated the putting experience as “satisfactory”

The authors wrote: “Most golfers are satisfied with green speeds within a wide range of ball-roll distances provided that they are uniform and consistent”

If you are interested in the full article here is the citation:

Dest, W. M., Guillard, K., Rackliffe, S. L., Chen, M.-H., and Wang, X. 2010. Putting green speeds: A reality check! Online. Applied Turfgrass Science doi:10.1094/ATS-2010-0216-01-RS.

If you don't have access to Applied Turfgrass Science you can email me and I'll send it.

They also wrote: “Original guidelines for the Stimpmeter stress the importance of using the device as a tool by which golf course superintendents can adjust their management practices to maintain more uniform and consistent putting conditions on the green and to meet green speed standards set by a quantitative measure (5,8). This minimizes the element of luck and thereby places more emphasis on putting skill (6).” As for me, I think I need luck, NOT skill :)

It's Waitea-licious!

Waitea, Waitea, every where,
Yellow rings all over my grass;
Waitea, Waitea, every where,
What a pain in the ass.
(apologies to Samuel Taylor Coleridge for bastardizing The Rhime of the Ancient Mariner)

OK - I get fooled more than I'd like to when it comes to recognizing turf diseases. A few weeks ago I received the photo of rings on creeping bentgrass (above) from Gabe Towers from Target Specialty Products in Arizona and said "that's take all patch!" despite Gabe thinking it was a Rhizoctonia disease. After isolations from the turf - we did confirm that the damage was caused by Waitea circinata var circinata aka "brown ring patch". Unlike the nice yellow rings that the pathogen causes on annual bluegrass, this is what Wcc looks like on bentgrass. Thus the name "brown ring patch" as described by Japanese plant pathologists who first characterized the disease on creeping bentgrass.

BRP is pretty active in California right now - showing up on both annual bluegrass and rough bluegrass putting greens.

One question that came up this week at a meeting in San Diego was "If I have active BRP going into spring aerification, should I worry about it?" I think that it shouldn't be a problem if you apply a good shot of nitrogen after core aerification - at least 1/2# N per 1,000 sq ft should help reduce down the severity of the disease. If it's still active a week or two after aerification, a shot of fungicide should help get rid of it, but the combination of N fertility and OM/thatch removal should help reduce the disease.

As far as fungicides, I heard some concerns over the short residual control that Endorse/Affirm was giving on greens. If you tank mix the polyoxin-D application with 1 fl oz of Banner MAXX, you should get 28 days or more control of the disease (outside of California, you could use 0.28 oz of Tourney or 1 fl oz of Trinity in place of the Banner MAXX in the tank mix if either Tourney or Trinity is available). A follow up application a week to 2 weeks later with 2.2 oz of ProStar will give you near cmplete control of the disease, but often with the increased N, the first Endorse or Affirm application with a DMI should do the trick.

Fairy Ring Activty
With spring coming in the West, we're also picking up some increased fairy ring activity. Green rings or mushroom on your turf are a sure sign of fairy ring activity . Although a number of fungicides can work vs fairy ring, it's also important to apply the fungicides in an adequate water volume or water it in - see Lane's fairy ring profile here, as well as Mike Fidanza's water volume and surfactant work here.

As mentioned in previous postings - using the magic plastic bag to see where the fairy ring is in the soil (near the surface or way down in the soil) can help you judge how far you need to push your fungcides into the soil profile with water to get good control.

In the photo above - you can see the white fairy ring mycelia in this sample (incubated overnight in a sealed plastic box) poking out from the soil (on the side of the plug) up to a few inches down from the surface. in this case - you'd know that you'd need to get the fungicide down to this level to get adequate control.

OK - that's it for this week. I'm back in DC after a week in sunny California, good thing the snow is finally melted here!

Signing off from the Right Coast....

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: 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: 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.

Anthracnose-0136After 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
Gray Snow Mold-0195
(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.
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