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Creeping Bentgrass Performance with Reduced Fungicide Inputs, Tim Sibicky, CDGA

September 3, 2010

Creeping bentgrass is used extensively on golf course fairways throughout the northern United States. It is typical for variety trials all throughout the country to use management practices where all diseases are controlled for comparison.

Currently, there is limited available research in cultivar testing for reduced fungicide input programs. Today, many golf course superintendents are looking to cut costs and reduce inputs to their largest acreages of highly managed turf, the fairways.

The objective of this work was to determine the susceptibility and performance of creeping bentgrass cultivars under a reduced fungicide input management program for dollar spot disease on fairways.

Twenty-four different cultivars of creeping bentgrass and one colonial bentgrass cultivar were selected for the study. Plots were established in October of 2008. Each plot is split in half with one half receiving fungicide applications and the other side receiving no fungicide. Fungicide applications of Daconil Ultrex at 3.2 oz. with Emerald at 0.18 oz are applied when a 5% percent threshold of dollar spot occurs on the cultivar ‘Declaration’.

The August 23 sampling date for the split plots shows that acceptable levels of visual quality are achievable when limiting fungicide applications. Best visually rated varieties under this reduced management include, Kingpin, Pennlinks II, SR1150, CY-2, Declaration, Shark, OO7 and Memorial. Cultivars rated at or below acceptable visual quality include T-1, Southshore, Imperial, Penn A4, Crystal Bluelinks, Bengal, Independence and Century. Meanwhile, all split plots left untreated produced unacceptable levels of turfgrass visual quality. These untreated plots had dollar spot levels up to 60-80% blighted turfgrass in some cases.

Dollar Spot of Fairway Bentgrass Cultivars

Visual Quality of Fairway Bentgrass Cultivars

Tim Sibicky
Chicago District Golf Association
11855 Archer Avenue
Lemont, IL 60439


New Turfgrass Disease Culprits

August 30, 2010

This article comes to us from David Maubach, Senior Sales Specialist, BASF Professional Turf & Ornamentals.

The presence of several new turfgrass diseases has increased on U.S. golf courses in recent years. Three new diseases in particular – Pythium root dysfunction, brown ring patch and rapid blight – are a challenge for course superintendents. Fortunately, researchers have made headway regarding how to detect and treat these destructive new diseases.

Tackling New Diseases
New turfgrass diseases can evolve for a number of reasons and several factors contribute to the prevalence of disease such as geography, moisture and temperature.

Stress caused by heat, drought and excess moisture can weaken turf and make it more prone to disease. Put simply, healthy turf is less susceptible to disease. The challenge with golf courses, particularly on the greens, is that turfgrass is kept short by plant growth regulators and/or frequent mowing, which causes stress.

Players expect superintendents to provide the best of both worlds – short grass and healthy turf. It is a difficult balance, especially when new diseases emerge and superintendents do not know how to treat it.

University and industry researchers are addressing these three emerging problem diseases. To avoid being caught off-guard, superintendents should take time to learn more about these diseases. Doing so will help identify and treat the diseases, and in some cases, avoid them altogether.

Pythium Root Dysfunction
Discovered in North Carolina in 1994, Pythium root dysfunction attacks putting greens and is limited to newly constructed greens less than eight years old. It is most commonly found in the Southeast, but also occurs in Midwestern areas with harsh summers. Bentgrass is most susceptible to the disease, which occurs on turf stressed from one or more of the following factors: high heat, repeated close mowing, low fertility schedules and drought.

Pythium root dysfunction causes the roots and crown of turfgrass to turn brown or black. The symptoms are most visible during the summer, but the disease actually spreads during spring and fall, when it is cool and wet.

Because symptoms are less prevalent on plants with a strong root system, there are several cultural practices superintendents can undertake to minimize damage caused by Pythium root dysfunction. Root enhancement techniques – specifically aerification, nutrition supplements, verticutting and reduced irrigation – are helpful in counteracting symptoms of the disease.

Irrigation management is also extremely important. Clay and compacted soils are more likely to harbor Pythium root dysfunction because of reduced drainage.

It is less difficult and less expensive to prevent Pythium root dysfunction than it is to try to cure it. Fungicides such as pyraclostrobin and triticonazole are two of the most effective at preventing the disease.

Dr. Lane Tredway, turfgrass pathologist at North Carolina State University, is one of the foremost experts on Pythium root dysfunction. To learn more about his research and information on NC State’s Center for Turfgrass Environmental Research & Education, visit

Brown Ring Patch
Formerly known as waitea patch, brown ring patch has been reported sporadically throughout the Midwest and is a mounting problem in Southern California. Occurring primarily on greens with high annual bluegrass (poa annua) populations, the disease is prevalent in warm and moist conditions.

Initial symptoms of brown ring patch are thin, yellow, concentric rings several inches in diameter that turn brown under hot or wet conditions. Once established, brown ring patch can quickly damage turfgrass. Temperature plays a significant role in regards to whether or not brown ring patch occurs. The disease does not spread in hot or cold conditions, but rather during times of mild (mid-60s to low-80s F) temperature.

Cultural control options of aerification and higher mowing heights are sometimes used to combat brown ring patch. Alternating among several fungicides – pyraclostrobin, propiconazole and triticonazole – has been an effective treatment.

Dr. Frank Wong, assistant plant pathologist at the University of California-Riverside, is considered one of the top brown ring patch researchers. For more information, visit UC Riverside’s Department of Plant Pathology and Microbiology at

Rapid Blight
Rapid blight occurs in the fall and winter, affecting several annual winter grasses used to overseed Bermudagrass. Affected species include ryegrass, annual bluegrass and poa trivialis. It is primarily seen in the Southwest, including Nevada, Arizona and Southern California, as well as on coastal areas in the Southeast and Northeast. Perennial grasses are not affected by rapid blight.

The disease is associated with a marine organism and cases of rapid blight rise significantly in areas where superintendents use reclaimed water or water with high salinity for irrigation. The disease can occur on any area that has been overseeded, but is usually treated only on putting greens.

Dr. Mary Olsen, plant pathology specialist for the University of Arizona-Tucson, has confirmed that rapid blight is caused by an obscure microorganism that prior to its discovery in turf was known to infect in marine plants such as seagrass, diatoms and algae.

Rapid blight shows itself as water-soaked, slightly sunken and darker looking turf. It turns yellow and dies in patches.

The primary cultural control option is to use better quality irrigation water, avoiding reclaimed water, if possible. Pyraclostrobin provides the most effective preventative control, with mancozeb as a less effective alternative.

Olsen is a leading rapid blight researcher. The University of Arizona’s Division of Plant Pathology and Microbiology is available on the Web at

Prevention, Education Key
To avoid being caught off guard by new diseases, it is important to stay educated on new diseases, be consistent with preventative tactics and devote time to detection efforts.

Part of being proactive is keeping up with the latest research and information about turfgrass disease. Superintendents who collect and absorb background information are better prepared when they encounter a problem – they know what they are dealing with and who can help them.

Some superintendents are quick to write off an undiagnosed problem as being untreatable by a particular fungicide they have already applied, so they simply retreat with a different product. Instead, they should take a turf sample and send it in to a diagnostics lab.

Fungicide manufacturer representatives, university extension personnel and other course superintendents are also good sources of information. It is wise to seek the help of others if they encounter an abnormality they do not recognize.

It may seem like common sense, but it is important for superintendents to walk their courses every day to keep an eye out for abnormalities. New diseases such as pythium root dysfunction, brown ring patch and rapid blight can cause problems quickly if undetected.

David Maubach
Senior Sales Specialist
BASF Professional Turf & Ornamentals


Research Update: Keith Rincker,

October 16, 2009

North Central Region Collaborative Effort...and the data says

Dollar spot was the talk for the last two weeks of September, but now the night temps will hold off any development except for a possible warm spell left in the year. Now is the time to look back and evaluate our dollar spot information. We had a chance to evaluate our new fairway bentgrass variety trial during the highest disease pressure of the season. The borders of ‘Alpha’ and several entries were lighting up! It has been a long road for this trial. Twenty nine bentgrass
varieties were seeded last year and then reseeded this May. Now we have lowered the height (0.75 inches) slowly over the summer and finally we got some disease.

Next year we will learn (again)
Next year we will get a better idea for disease resistance of these varieties. So far our variation is still large and another years worth of data will be needed to determine the genetic resistance in the new varieties like ‘CY-2', ‘Kingpin’, ‘Shark’, and ‘007’. This data does show that varieties have been released with comparable resistance to ‘L-93’. Hopefully with more time we can say that there are a handful of varieties with greater resistance than ‘L-93’. In National Turfgrass Evaluation Program (NTEP) trials, ‘Declaration’ has shown promise. ‘Alister’ is actually a colonial bentgrass species. In previous research on Sunshine Course, colonial varieties are damaged by brown patch and weeds become a problem.

The “take home message”...
The goal of this research conducted here in Lemont and 11 other Midwestern universities is to determine how many fungicide sprays are needed when varieties with greater resistance are used.

The L-93 Story at North Shore
This year at North Shore Country Club we set out treatments on a fairway strip of ‘L-93’. Only one application was made on May 14 and the plan was to see which treatments provided the longest control. Bayleton, Emerald, Daconil, Banner Maxx, and Chipco GT were all applied and we waited for dollar spot. Mid June came around, and no dollar spot – too cold. The beginning of July came and only a tiny bit of dollar spot. The beginning of August came around and finally dollar spot reached 1-3%in all plots. Fungicide or not, all treatments were the same for percent dollar spot incidence and plot visual quality.

No differences...
We found no differences in our statistics. What did we learn? Maybe May 14 is too early for dollar spot control. Maybe we can reduce our fungicide inputs by utilizing genetic resistance and eliminating one or two applications early in the summer. Our heads are already spinning around to design research in 2010.

Emerald for next year’s research...
So far our thoughts are to pick one fungicide and apply on selected dates from May through June or July on each ‘L-93’ and a bentgrass/Poa mixture. This will give us an optimal timing for first application to control dollar spot on two different turfgrasses. For now we will write down our thoughts and continue to analyze the research.

Keith Rincker
Chicago District Golf Association
11855 Archer Avenue
Lemont, IL 60439


The Importance of Understanding Product Labels: Reviewing Labels Improves Product Performance

March 23, 2010

The golf season will soon be getting underway as most golf courses in the state are preparing to open. The start of another season signifies the beginning of pest and disease pressure. Areas affected by gray snow mold should begin to recover as the grass begins to grow. Pressure from other mild weather diseases such as pink snow mold and cool-season brown patch will persist longer into the spring. As you prepare your plant protectants, be sure to revisit the product label as this information can change over time.

Editor’s note: The remainder of this article was submitted by Todd Burkdoll, BASF Professional Turf & Ornamentals Technical Specialist.

Product labels aren’t the type of reading material that you can snuggle up with—but they’re also not the kind you can ignore or just skim through before filing away.

Labels deserve routine attention beyond the one-time, quick read after purchase. However, it can be common practice to follow use recommendations from colleagues and distributors without analyzing the important details explained on the product’s label. But doing so can save money, prevent injury and help grow better turfgrass by ensuring product performance.

Most people using fungicides, herbicides and insecticides only ask themselves, “What product do I need to control the weed, insect or disease and what rate do I apply?” Rate information is essential, but labels provide a technical breakdown and need-to-know information prior to application. Here are five key areas to read on a label:

1. Mix Mindfully
The tank mixing section of a label lays out exactly how to combine a product with other additives. Glazing over these guidelines can create an un-usable compound, clog application equipment and reduce efficacy.

The basic rule of thumb—mix dry materials first, then add liquids—may not ring true for all products. One must be mindful of variances between generic and patented formulas and know that even though an active ingredient may be the same, its formula could require different a mixing order. So don’t rely on old standards—get up to speed on the label’s specifics before adding each product to the tank.

2. Follow Special Statements
Special statements on a label clearly communicate how to use a product for particular conditions. In uncontrolled climates, weather is an important variable to consider.

Be sure to make note of the rainfast or drying times mentioned in a special statement or you may lose your valuable pest control efforts to precipitation. Retain product effectiveness by making sure spray technicians are also in-the-know about circumstances included in the special statements section.

3. Get to Know Group Numbers
Group numbers help avoid the risk of disease resistance by identifying which fungicides, herbicides and insecticide products operate under the same mode of action. Usually included on the first page of a label, group numbers make it easy to organize products with different modes of action into a rotation program. For example, if you notice signs of resistance after using a fungicide in Group 1, try using a product with a different group number in the next application.

4. Acknowledge Agricultural Use Requirements
Agricultural and non-agricultural use requirements on product labels are important and vary depending on product use. A greenhouse or nursery employee, for instance, may use the same product as a turf professional, but has to abide by a completely different set of rules with regard to protective equipment and re-entry interval. Failing to read this section of a label could harm employees, turf or plants and the environment.

5. Follow restrictions and limitations
Carefully read the “general restrictions and limitations” section on your product labels. Knowing the “do not” statements list can mean the difference between having healthy turf and plants—or damaging an entire fairway or landscape bed with poor application practices. Brushing up on labels you haven’t read since last year can make all the difference.

General suggestions
Making a 10-15 minute investment in reading a label can save a lot of time and hassle compared with the fallout of misusing a product. Schedule a label date once a year where you can carefully re-familiarize yourself with old labels and dissect the details of new updated labels. The best place to obtain current labels is

Todd Burkdoll is a Technical Specialist in the Western U.S. for BASF Professional Turf & Ornamentals. Todd can be reached at


Plant Growth Regulator Effects on Seedhead Control and Early Season Dollar Spot, Tim Sibicky CDGA

May 20, 2010

We are testing a variety of plant growth regulator products and fungicide chemistries for efficacy on early spring seedhead control and possible disease reduction. This study is being conducted on a fairway mixed stand (50/50) of Poa annua and creeping bentgrass and has been initiated to show visual turf quality differentiation of the various products. Last season, test strips on a nursery green at North Shore Country Club in Glenview, IL showed considerably less disease when a plant growth regulator, Embark, was applied once during June. The early season applications as seen in the bar graph below for “Visual Quality” are at 21 and 28 days after treatments (DAT).

The first application was critically timed to coincide with forsythia bloom on April 14th. There are three Embark treatments all at the 40 oz/acre rate; Embark alone, Embark with Primo 0.125 fl oz/M and Embark with Primo 0.125 fl oz/M and also Signature 4 oz/M. This series of Embark treatments was only administered as a one time application due to a high amount of tip burn on the creeping bentgrass and chlorosis on the Poa annua. All treatments were within labeled rates. The result is poor visual quality of turf in this early spring period. However, all of the Embark treatments were excellent at eliminating all Poa annua seedheads (100% control).

Two combinations of Proxy and Primo (5 fl oz/M + 0.125/M) were tested, at a 21 day interval with one including Signature at the 4 oz/M rate. However, neither of the two mixes resulted in greater seedhead suppression than any Embark combination (see graph). The visual quality for the Proxy + Primo + Signature yielded better quality at both the 21DAT and 28DAT (7 days after second application), but interestingly, there was no statistical differences between the treatment that contained only Proxy + Primo and any of the Embark treatments.

So, the question that is brought to my attention from the data is whether there is some sort of synergistic effects in mixing Proxy + Primo + Signature? On the flipside, we don’t see any of these effects in tank mixing with Embark, so this means we can rule out that it may have had something to do with a pigmented spray or not. Secondly, will the sacrifice in early season turf quality using Embark pay off when we get to the heat of the summer? And lastly, is it worth the dollars to apply fungicide this early for dollar spot when we have very low disease pressure? Over the next few weeks, we will likely begin to start seeing dollar spot and I will be excited to see how these early season applications of plant growth regulators and fungicides function in producing good turf quality and resistance to disease.

Tim Sibicky
Chicago District Golf Association
11855 Archer Avenue
Lemont, IL 60439


The Year of Brown Patch, Tim Sibicky, CDGA

July 21, 2010

Above normal daytime temperatures of 90+ degrees have been accumulating quickly (now up to 11 days in Lemont, IL), and the combination of high nighttime temps and high dew points has created a precarious situation for the rapid appearance of brown patch. This soilborne fungal disease is caused by the pathogen Rhizoctonia solani. Recent weather has been fairly dry since July 4th, and although it has been much needed for superintendents, it has added further
environmental stress to any previously weakened turfgrass plants. Damage by Rhizoctonia is now obvious (Figure 1).

Damage by Rhizoctonia

Research trials on Sunshine Golf Course have been providing excellent data on product testing for dollar spot. In addition, the exceptionally conducive environmental conditions for development of brown patch have allowed us to monitor effects of the products on both diseases. Untreated plots in all replications on July 15 showed greatest disease pressures at 40% brown patch and 15% dollar spot. Visible symptoms for brown patch were most severe on untreated plots as expected (Figure 2).

Visible Brown Spot

Of fungicides, the 21 day interval of the Emerald treatment at 0.18 oz had highest brown patch visibility at 20%, which when compared to the control was still far less. Other treatments that showed amounts of brown patch were Chipco26GT (dicarboximide family), Insignia (QoI), and the 14d low rate of Reserve (chlorothalonil + DMI). The fungicides that performed well with no visible symptoms of brown patch disease have been Daconil Ultrex (chlorothalonil), Honor (QoI
+ carboximide), Concert (chlorothalonil + DMI), Insignia, Renown (chlorothalonil + QoI) and Reserve (chlorothalonil + DMI) at both the 21d and the 14d high rates.

Brown Patch Disease

Treatments that have provided the best dollar spot disease control so far include: Daconil Ultrex, Chipco26GT, Heritage + Daconil, Insignia, Concert and Reserve at 21d (high rate). Treatments of Emerald, Honor, Renown and Reserve at 14d (high and low rates) all provided good levels of disease control. All fungicide treatments provided acceptable levels of quality except for Concert, appearing off-color (due to the DMI-propizole) and with coarser visible leaves.


Tim Sibicky
Chicago District Golf Association
11855 Archer Avenue
Lemont, IL 60439


Diagnostic Update: One of our more serious fungal diseases arrived last week

June 27, 2011

This post comes to us from Dr. Derek Settle from the Chicago District Golf Association

Late last week, I heard word that a green was thought to be showing symptoms of anthracnose basal stem rot.  On Monday, in the rain, I made the visit.  Indeed the green did have the typical signs.  Poa annua was bright yellow whereas creeping bentgrass was fine.  Areas of the green that would tend to show wilt stress were most affected.  With a hand microscope that the Superintendent sues for field diagnosis, we both were able to see hair-like state and black discolored stems.  The stems were easily detached when pulled because they had rotted.


The main cause was determined to be two-fold. 1) The weather.  Coincidentally, I had noted that low relative humidity values were striking on Monday and Tuesday (this was already unlike season 2010 which always seemed blanketed in high humidity).  The timing of the outbreak on Wednesday suggested the primary stressor was midday wilt.  2) Some DMI fungicides used for fairy ring prevention have little efficacy against anthracnose basal stem rot.  Our course of action was to reduce plant stress on affected greens.


Reduce wilt stress: monitor greens closely for midday wilt.

Reduce fertility stress: increase nitrogen input as is feasible.

Reduce mowing stress: raise height of cut as is feasible.

Select best fungicide: use published fungicide trial information from plant pathology researchers across the United States.


For up-to-date fungicide recommendations I suggest the University of Kentucky 2011 Chemical Control of Turfgrass Disease guide


Derek Settle, PhD
Director of Turfgrass Program
Chicago District Golf Association
11855 Archer Ave
Lemont, IL 60439


Holy Mycelium!

July 8, 2011

When I arrived to work this morning I was greeted by an outbreak of dollar spot. We had been on the dry side since the last week June but we received 1.33 inches of rain yesterday. The abundant rainfall coupled with the warm overnight temperatures, and high humidity led to conditions that were very conducive for dollar spot. Mycelium was especially abundant in our untreated creeping bentgrass areas.

Below are a few pictures from one of our creeping bentgrass fairway trials. This particular trial has 24 different cultivars of creeping bentgrass. Each plot is split in half and is either untreated or receives applications of Daconil and Emerald.

The objective of the trial is the determine the susceptibility of creeping bentgrass cultivars to dollar spot when maintained under reduced fungicide applications. Applications of the Daconil and Emerald mixture are scheduled based on a threshold of dollar spot severity in a cultivar with a high level of dollar spot resistance. Declaration is the indicator cultivar in this trial.

This picture shows the Declaration plot in one of the replications. The left half of the plot is the treated side and before today had only received one application on June 6. Declaration is a recently developed cultivar of creeping bentgrass that has relatively high resistance to dollar spot compared with other cultivars. Even the untreated side (right side) is holding up fairly well without receiving any fungicide to date.

This next picture shows a Penn A-4 plot. Here the right half of the plot is the treated side. As you can see, there are noticeable differences between cultivars of creeping bentgrass with respect to their disease resistance.

This trial along with many others will be on display during the Iowa Turfgrass Institute/Iowa State University Field Day on July 21. There is still time to register for the event.

Marcus Jones
Assistant Scientist


Name Brand vs. Generic Fungicides

January 4, 2010

This summer at Des Moines Golf and Country Club, Director of Grounds, Rick Tegtmeier, CGCS and two ISU Interns conducted a fungicide study that compared name brand versus generic products for dollar spot control. The two interns from Iowa State University were, Tyler Boley and Tayler Riggen. They worked closely with Luke Dant from Syngenta Professional Products to set up a replicated study on the golf course.

How they did it
Plots were arranged on fairways at two different locations on the course in order to account for spatial variability. The fairways contain ‘Penneagle’ creeping bentgrass maintained at 0.5 inches. One set of plots were located on the north course and the other on the south course. Each set of plots was replicated three times. Treatments included an untreated control, Daconil WeatherStik, Manicure 6FL, and Echo 6F ETQ fungicides. All products were applied at a rate of 2 oz/1000 ft2, to deliver the same amount of active ingredient, using a backpack sprayer with #8002 flat fan nozzles. Carrier volume was 44 gallons/acre. Spray applications began on May 14 and concluded August 13. Applications were made on 14-day intervals for a total of 7 applications. Percentage of turf affected by dollar spot was visually estimated on July 1 and August 14.

What they found
Each plot in the study succumbed to some dollar spot, but it was clear there were differences between the products in our study (Table 1).

Similar trends were evident on each of the test plots between the north and south courses but the disease pressure on the north course was far more severe. An application of Bayleton was made to the plots on the north course on June 22 to help reduce disease pressure. The main findings from the study are summarized below.

- Control plots sustained significant damage and possibly needed reestablishment.

- All chemicals succumbed to some breakthrough if applied on 14-day intervals. At the rate used in our study, shorter intervals are needed with all products.

- Manicure 6FL seemed to have good control until approximately 10 days after each application. After that, there was significant breakthrough.

- Echo ETQ had less than desired control through the 14-day period between applications. Echo ETQ fungicide is green in color which is designed to help cool the turf and in turn help prevent disease. In our opinion, the green colorant has little effect and was barely noticeable after being sprayed.

- Daconil WeatherStik had acceptable control until 13 and 14 days after application, and then some small breakthrough was evident. Recovery was not exceptional, but due to better initial control of dollar spot, Daconil provided the best control of dollar spot.

- One option would be to compare prices of products to see if Manicure 6FL or Echo ETQ could be applied on 10 day intervals for lesser overall price, however; this would increase labor costs and wear and tear on spray equipment, possibly negating any cost savings by purchasing these generic products. In our study, Manicure and Echo provided nearly the same level of dollar spot control.



Summer Patch Showing Up On Kentucky Bluegrass Turf At Research Station

July 6, 2015

Summer patch, caused by the fungi (Magnaporthe poae), is showing up on Kentucky bluegrass turf at the research station in central Iowa in early July.  I am also getting some calls and pictures from people in the state asking about this problem.

This disease forms an interesting pattern in the turf.  The patches are 8 to 15 inches in diameter.  In early stages, they will have a brown ring around the outside and a green center.  In more advanced outbreaks, the entire area may become blighted.  The symptoms are often referred to as "frog-eyes".  There are other diseases that form frog-eyes, but these generally show up at other times of year.  Summer patch generally begins in early July in central Iowa.  I normally associate it with years that begin wet and then turn hot and dry.  In this case, the area is irrigated.  We have also had a wet spring and this area was not under moisture stress.

The development of the frog-eye is generally attributed to the fact that this organism is generally a saprophyte, an organism that feeds on dead organic material.  The infestation begins in the center of the spots and begins to move out as it consumes dead organic material.  Under the right conditions, the organism will begin to attack living tissue and forms the dead ring.  

Systemic fungicides that are taken up by the plant are the only materials that will control this disease.  It does little good to treat once the symptoms are present. The condition will go away by fall.  The area should be treated with systemic fungicides labeled for Summer Patch the next year before the symptoms develop.  This is of course hard to do and good record keeping is a must for this disease.

Core aeration in the fall can also improve growing conditions for the grass and may reduce the severity of the symptoms.  The pictures above are taken from an area where the disease appear nearly every year.  We leave the area untreated so that we can show the condition at the annual field day.  This years field day is on July 23, 2015.