Custom Search

Some disease and a shout out to Dr. Vittum

Tomorrow marks the start of yet another month gone by and with it usually cooler temperatures. In State College, temperatures are already decreasing with the highs only in the low to mid 70s. In Maryland, high temperatures are only getting into the low eighties, but the nighttime temps look to increase to near 70 by next week (once again if the weather reporters are correct which is usually a safe bet). Moving north to Westchester, NY and into New England, temperatures are set to be in the upper 70s and mid-70s, respectively. This means that diseases should start to subside and your interns have all headed back to school just in time to miss your fall core cultivation and leaf cleanup!

Disease activity continues to vary by region. Dollar spot continues to be a problem for most and is increasing for others. Brown patch is just about done and any new flare-ups will likely just be superficial and cause little real damage. One problem that has been a problem among superintendents managing Perennial ryegrass is gray leaf spot. This could continue to cause problems, especially where ryegrass is being overseeded into thinned areas (although you should have any thinned areas in this wet year). Another potential problem that was brought to my attention last week was the recurrence of an "unusual" Pythium patch problem on annual bluegrass. I don't have the time to get into this now, other than to say that it has been something I have been tracking for the past 4 years and seems to be a real problem for those that get it. It is a Pythium disease that selectively targets annual bluegrass with symptoms similar to summer patch. I plan to dedicate a full post to the subject next week, but for now if you think that you have summer patch on your annual bluegrass putting greens, consider sending a sample out to get checked for Pythium.

In the meantime, I thought that I would give some promotion of Dr. Pat Vittum's updates about grub and annual bluegrass problems in the Northeast. Pat is a GREAT resource for those of you in New England and was a tremendous supporter of my efforts while I was at UConn.

UMASS Update by Pat Vittum:
White grub development varies greatly from one location to another this year. Normally we would expect European chafers to emerge in mid-June and start laying eggs shortly thereafter. Oriental beetles usually are a week or two behind that, and then the Japanese beetle adults emerge around July 4th. But this year, perhaps because of cool soil temperatures, the Japanese beetle adults in particular were very...Read Full Story Here.

Annual bluegrass weevils. We are seeing activity and damage from the third generation in several locations from the metropolitan area up through Hartford. Based on our samples, most of the weevils are already large larvae or pupae, so the worst should be over. Now that the weather is breaking (lower temperatures and much lower humidity), the turf should be able to...Read Full Story Here.

OH, and one last thing...I am glad that I was not the only one who voted "No, this blog stinks". It appears that two others were in agreement with me. I just wonder if they two were blog authors or a golf course superintendent angry that there was no "PlayTurf" cover for August? Either way, it looks like most of you find the information useful so we plan to keep providing updates through the season! Thanks for all of your support and spread the word.

Big Bucks, No Whammy

Dang, I had several photos that I wanted to include today, and a graph showing dollar spot progress in one of my trials, but sadly my computer (with all my photos, etc) is not working at all, and the IT guy is not around. I'm camped out at another computer right now, in the diagnostic lab.

The thing is, for the past two days I've been joking with friends about Whammies. Remember that silly game show with the Whammies? I used to watch it when home sick from school, or on summer break. Big bucks, big bucks, no Whammy. Well, this afternoon the Whammy didn't steal my money, but he did wreck my laptop, and that's even worse.


There is a ton of dollar spot out there. At our research center we have dollar spot in the greens, fairways, and in the perennial ryegrass lawn/rough height areas. This morning was very dewy and there was some dollar spot mycelium in the rye. I even had a sample this week of dollar spot from a bermudagrass home lawn. Late August into September is when we get severe dollar spot, sometimes taking grass out down to the ground on putting greens.

I was surprised to see a little bit of faint brown patch on the putting green at our research facility this morning. In fact, I wasn't even the one to notice it first--my colleague Dr. Jack Fry spotted it before I did. It has been cool lately, but the last couple of days have been warmer and very humid, so I guess it was not so surprising after all.

Other than these couple of diseases the weather conditions have been fantastic lately for cool-season turf. It's the last Friday in August, and there is always a sigh of relief when turning the calendar over to September. The summer stress is over. As a superintendent once told me (during a particularly hot/stressful summer), "God grows the grass 9 months of the year, then turns it over to us for June, July, and August."

I thought I'd also mention that in landscape/ornamentals there has been a rush of tree and shrub samples in the past week. Just like turf most of the time, most tree samples are NOT diseases--it is an environmental stress issue. But there have been a ton of actual diseases lately. Culprits have included:bacterial leaf spot in English Ivy; bacterial leaf spot in hydrangea; septoria leaf spot in dogwood; cercospora leaf spot in lilac; cylindrosporium leaf spot on spirea; mycosphaerella leaf spot on ash. We don't see too many bacterial leaf spots in Kansas. Fungal leaf spots require wet weather, but bacterial leaf spots require even more. This year was very wet in many locations, wet enough to trigger bacteria. That is darn wet.

That's it. I hope the Whammy doesn't get you, or your turf.

The A-Word, R-Word and S-Word

Just a few quick notes from the road - I'm somewhere between Jim and Megan's territory in St. Louis, Missouri on my way from St. Paul, Minnesota to Alexandria, Virginia today.

I talked a lot about anthracnose in last week's posting and the "A-Word" has been on alot of people's lips this last week in the West.

The "R-word" (Rapid Blight) also was pretty popular on Poa greens in California last week, especially in coastal locations.

The "S-word" (Summer patch) has not been super rampant, but continues to annoy superintendents here, magnifying any heat or stress damage.

Expect more of the same this next week on Poa greens for hot inland areas (anthracnose & summer patch) and moderate coastal locations (anthracnose, summer patch & rapid blight). The Central Valley (Fresno ) area is still staying warm at night and Pythium on cool season turf is likely there.

As for Rapid Blight: If you have TDS readings above 2.5 dS/m (0.5 on the Oakton TDS-4), you are likely at risk for rapid blight development. Applications of Compass, Insignia and Fore will suppress the disease but it will keep coming back until you get your sodium levels down. Nothing beats a good leach for Rapid Blight control, but it's also a pain in the butt to do properly.

Just a few more weeks until the end of summer – if you can hold out for another 4 weeks, life will likely get much easier!

Preventative Fairy Ring Applications

No this is not the time for preventative fairy ring applications. Rather I am writing this post to discuss a small trial we conducted this year. On a chipping green at University Ridge Golf Course (Thanks Aron!), we established a preventative fairy ring trial. Last year we observed a severe, uniform outbreak of fairy ring on this particular green. Aron and I were interested to see if the preventative applications Dr. Tredway and Dr. Settle have been advocating work in Wisconsin. We applied fungicides when soil temperatures reached 55 F and made a second application one month later. All treatments were watered in immediately following application with a 1/4 inch of water. The treatments included Triton Flo, Heritage, Disarm, Bayleton, Insignia, Tourney, Triton, Prostar, and a non-treated control.

The outbreak this year was not as uniform as in the previous year. One very large ring developed in one corner of the plot. Yet, the ring did not reach the non-treated control plots, darn! Nor did the ring reach the Triton Flo or Trinity plots. However, we did see some distinct differences in the plots where fairy ring did develop. One disclaimer, the large fairy ring only encompassed one side of rep 1 and 2. We observed a break in the green ring in the plots treated with Disarm, Prostar and Tourney. The ring was present in the Bayleton treated plot, but we did not observe a break in the ring. Although we observed different efficacy than Dr. Tredway and Dr. Settle, it is fairly obvious to us that preventative applications are very effective. Thank you Dr. Tredway, Dr. Settle, and Lee Miller! We do have pictures of the break in symptoms, but my computer did not want to cooperate with me tonight. I didn't follow my six P's :)

This was the first year we conducted a study like this and we are planning on repeating the study next year. We did observed visual differences, but I cannot discuss statistical differences since disease did not develop in the non-treated controls. Lee Miller and Dr. Settle have more data on preventative fairy ring control than I do, so I still think Bayleton is a good choice for preventative fairy ring control. Based on a recent presentation by Lee Miller, they found that Triton Flo and I believe Tourney worked well too.

Not much coming through the diagnostic lab last week or this week. I have seen a lot of rust in Kentucky bluegrass roughs, but other than that I think the weather has kept most diseases at bay. Now golf course superintendents are thinking about snow mold and I'm sure hunting seasons!

I am looking forward to teaching my first class at UW-Madison this semester. Its not much, just a special topics course on Turfgrass Pathology. It should be a lot of fun and the best part is the students get to do most of the talking!

Poll Results: and the winner is...

The results from the poll posted a couple of weeks ago is in and dollar spot is hands down the winner, with anthracnose and Pythium blight a distant second. A total of 41% of those voting indicated that dollar spot was their biggest challenge. This comes as no surprise to me as that week (August 9-15) marked the real "start" to intense dollar spot outbreaks in our area and apparently many other areas as well.

It seems that dollar spot gets a lot of attention on this blog as many posts have been dedicated to discussing this chronic disease. For this reason, I decided to show some of this year's "early season" dollar spot trials conducted at Penn State. I have been working with early season dollar spot since 2005. In most years, dollar spot can be suppressed with early season fungicide applications. Exceptions occur in atypical years in which the onset of dollar spot is delayed beyond what would be considered typical (late May to early June for most parts of the Northeast). Although dollar spot did not come on with a vengeance until July in 2009, data seemed to follow previous years. In our 2009 trials, Curalan (1.0 oz) again provided the best suppression of dollar spot over the course of the trial. Emerald also provided good control. Prior to a major outbreak of disease in early August, Curalan plots had an average of only 3.5 infection centers per plot (18 sq ft) when compared to the untreated control plots which had an average of 26 infection centers.

From the data (and previous observations at Penn State), it appears that resistant strains of the pathogen at our research plots limit disease suppression with the DMI fungicides. In previous trials at UConn where resistance was not an issue, good control with the DMI's was achieved. My observations from the past 5 years of data indicate that delaying the onset of dollar spot through early season fungicide applications serves two functions: 1) the delayed onset of disease gives superintendents more time to catch the disease once symptoms do start to appear; and 2) dollar spot suppression later in the season appears to be manageable as the disease doesn't appear to get out of hand during the fall.

Other issues in the region...
Perhaps if the poll had been posted one week later anthracnose may have taken the lead. In last week's posts from the West and South Central, Frank and Megan posted about rising anthracnose samples in their regions. Reports around the Northeast (from Rutgers) indicated that anthracnose activity was picking up as well. A walk through some of our plots at Penn State also indicated that anthracnose was increasing. However, this increase in anthracnose was on the creeping bentgrass. Disease activity on our annual bluegrass trials, however, remain very low. Pythium blight was also ranked as a moderate problem and the disease did make an appearance on some fine leaf fescue plots in the last week or so. At this point in time around the region, you can find just about every typical disease including summer patch, fairy ring, anthracnose, Pythium, brown patch, dollar spot, and others. Everyone SHOULD be able to see the light at the end of the tunnel, however, as core cultivation programs are about to begin and temperatures suitable for turfgrass growth resume in the next few weeks.

South Central is on the anthracnose train, too

It seems like autumn, with highs in the 70's and lows in the 50's. I'm enjoying it, but it makes me feel all confused inside. Is it really August in Kansas?

It's been interesting to read the posts about Civitas. We have not tested this product here yet. When I hear "horticultural oil" it makes me wonder about phytotoxicity, too, since those types of oils have been known to cause damage on other types of plants. So, I'm curious how it would work in our Kansas weather, both with efficacy and safety. Maybe we'll get our hands on some for a trial.

Dollar spot

Dollar spot continues its usual end-of-August surge. We have it in greens, fairways, and even in some Kentucky bluegrass roughs. The second photo shows a typical lesion on KBG.


Like some of my colleagues have reported this week, we've got some anthracnose rolling here. I had an email last week from a superintendent who reported some anthracnose coming in after some stressful conditions due to a tournament. Now that it's over, he's adding a dash of extra N and raising the mowing height a little bit. This should alleviate stress and help with recovery.

Just a short while ago today I had a photo come in by email (see below), then a physical sample followed. The sample was loaded with the characteristic dark spines of the anthracnose pathogen along with tons of spores.

Megan survives golf tournament

I am a pretty poor golfer, but I got suckered into playing in a best-ball scramble with some colleagues the other day. I've never played 18 holes before in my life, let alone on a challenging course (Colbert Hills). I've only played a few 9-hole/par 3 places, and that was a long time ago.

I did play in a tournament with Frank when we were students. My most vivid memory is Frank falling out of the golf cart while I was driving. He was there, and then suddenly he was gone. We probably won the prize for team beer consumption that day, and that may have contributed to his stunt roll out of the cart. I also remember making a long tee-shot that soared into the trees and hit a port-a-potty with a resounding crash.
As for the game this week, I only swung and whiffed a couple of times, I had a few nice shots, and in fact we used my shot on a number of occasions. I also discovered that the 7-iron is my lucky club, and I should just stay away from the driver. Too much can go wrong with that one. But, my real secret weapon was my pack of Sponge Bob Square Pants golf balls. My team ended up winning, and I think that was a deciding factor.

Look at the pretty zoysia at Colbert Hills

My teammate (Dr. Steve Keeley) tees off into the rolling prairie hills.
See the lovely big bluestem (tall native grass, with a brown cast) beyond the teebox.

Dans la Merde in the West

Dans la merde is a colorful French term that basically translates into "in the sh*t" and is a good term to describe superintendnets who are currently behind the eight ball fighting active foliar anthracnose outbreaks on annual bluegrass greens in the West.

Right now, anthracnose is coming into our diagnostic lab left and right. It's likely a result of the up and down heat spikes and we've had throughout the summer here in the west.

Although anthracnose should be managed with a combination of solid cultural practices (see and a solid preventive fungicide program, summer stress and common practices related to tournament prep (low mowing heights, holding back N, drying down greens, etc.) or just high traffic and play can put superintendents in a bad spot. If you find yourself dans le merde, here are three suggestions that may help you get back on top of anthracnose before it's too late

(There are additional things you can do to help pull yourself out of an anthracnose outbreak, these are just three of the most common things to consider - I'd welcome any additional comments from the NE, SE, M and SC as well!)

1. Fungicide applications
If you have active anthracnose on greens, chlorothalonil is your friend. Inexpensive and not at risk for resistance, it can be used aggressively as a "eradicant" application to kill spores in acervuli and prevent new infections. Label rate applications 7 days apart should be made to halt infections in their tracks. You can mix chlorothalonil fungicides with other anthracnose-active fungicides like Medallion and Endorse safely in a rescue type situation. Chipco Signature tank mixed with chlorothalonil can also be a good option. DMI-fungicides like Banner MAXX can also be mixed with chlorothalonil, but be aware of potential PGR-effects when using these at high rates or high temperatures. Beware of using QoIs (Heritage, Insignia, Compass, Disarm) or thiophanate-methyl containing fungicides (Clearys 3336, Fungo, etc.) by themselves as rescue applications. Resistance is a problem for these already and using them as rescue materials is a good way to lose them due to resistance (that's a GCSAA class all to itself). In any case, chlorothalonil can do a lot of work for you as a rescue fungicide, and also beat back any other secondary pathogens coming in to the damaged areas or algae that can fill into thinned areas on greens.

When using contact fungicides like chlorothalonil, it's very important to get good coverage. Apply fungicides in at least 2 gallons of water per 1,000 sq ft for adequate penetration of the fungicide to the lower leaves and crown. Flat fan or air-induction flat fan type nozzles, that produce smaller sized droplets, are much more effective than rain drop or flooding wide angle nozzles for getting the best coverage with contact fungicides.

2. Fertility
Assuming that you can get sufficient knock down of he pathogen, it's important that surviving Poa has enough N to push back and recover from injury. Light applications of N (0.125 to 0.25 lb N/1,000 sq ft) should be made to get your Poa back on its feet. Apply as needed to get regrowth and recovery from damage; but excessive amounts may cause some excess growth and scalping if you're not careful. Although N is the most important component, additional P and K can also help. A 20-20-20 may be a good choice for recovery from anthracnose damage.

3. Irrigation
Once you're hit with anthracnose, don't overwater damaged areas in hopes of increasing damage recovery. Overwatering is just as conducive for anthracnose as is drought stress. Irrigate based on ET-needs, but make sure to mist/syringe greens in during the hottest periods of the afternoon to minimize heat stress on weakened plants.

Hopefully, with some TLC (plus fungicides, nitrogen and irrigation management), you can get outta the merde and back to normal practices on greens. Often, anthracnose is linked to other environmental conditions or agronomic practices (compaction, black layer, drought stress, etc.), so make sure to address those issues as well while you are in "rescue" mode.

Just an observation: If your anthracnose if plowing right through preventive Heritage, Compass or Insignia applications…. Guess what, your anthracnose is probably QoI-resistant. If your anthracnose is plowing through preventive 3336 applications (or any thiophante-methyl containing material), you've probably got benzimidazole resistance. Check out our anthracnose powerpoint here if you haven't already seen it for some chemical control alternatives:

Other Merde...
Over the last week, we've been absolutely slammed by diagnostic samples in the lab. In addition to anthracnose, the usual suspects are still active, such as brown ring patch, summer patch and rapid blight. Samples coming in with Bipolaris, Curvularia, and Leptosphaerulina (especially on fairway and rough samples) are indicative of summer heat stress on cool season turf.

With temps in the 70s and 80s in coastal locations, I would suspect rapid blight be pretty active in salt affected locations, as well as brown ring patch and even dollar spot. The Central Valley (Fresno) and deserts will have to contend with night time temperatures high enough to flare Pythium on cool season turf. Expect anthracnose and summer patch to be calling on your annual bluegrass greens through out the state.

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

Novel Dollar Spot Control Programs

Dollar spot has really been the only challenge this year for golf course superintendents. With the recent economic downturn we are investigating ways to help superintendents reduce fungicide expenditures while maintaining quality playing surfaces. I have mentioned our dollar spot forecasting project, in collaboration with Dr. Damon Smith at Oklahoma State University, in previous posts. We are applying the preliminary model Dr. Smith developed in Oklahoma in our environment in Wisconsin. To date, the model has accurately predicted dollar spot development and making applications based on the model has resulted in 4 fungicide applications this year. When we compare efficacy to other fungicides either applied on 14-day intervals or 21-day intervals, the forecasting model holds up well. The one exception was a high pressure weekend and some dollar spot developed in the forecasting plots. The graph at the top left of this post depicts our results so far this year. The red arrows indicate when the model triggered and the blue arrows indicate when we made a fungicide application for just the forecasting plots.

The model did trigger before June 22 as a result we made a fungicide application on June 16th. Typical dollar spot programs in the Upper Midwest start on June 1, which would result in 7 applications when repeated every 14 days. For the 21 day treatments we have made 5 applications so far. Either case we can save either 1 or 3 applications per year. Currently we are putting numbers to these savings. We are using a municipal course, high-end public, mid-range private and an elite private course. Hopefully this will make are numbers relevant for a lot of turf managers. Please stay tuned because there is more to come!

Another project we are working on is expanding early-season dollar spot control. Basically we made a single early-season application and followed those applications up with 3/4 rates of Banner Maxx/Daconil every 21 days or full rates of Banner Maxx/Daconil every 28 days. Interestingly, full rates applied on 28 day intervals are providing the same level of control as our conventional program. We have not started our economic analysis of this project, but I know we have saved at least one fungicide application in this experiment. Again please stay tuned to this project too.

I am very excited about Lane's post yesterday! I saw the data with Civatas and I was excited, but we have not tested the product in the Upper Midwest. I know Dr. Derek Settle has, yet I cannot remember what he found. Civitas is scheduled in our snow mold trials this year, so we will see how it holds up. As always nice work Lane.

Megan's story about visiting with Aron Hogden is pretty funny. Poor Aron thought she was just a normal person coming over to lecture him about spraying. Aron had no idea that he peaked the interest of a turfgrass pathologist! Megan you are lucky you got out there without an inqusition from Aron.

Civitas shows promise for control of dollar spot and brown patch

Since the new fungicide Civitas was unveiled at the GIS Show in New Orleans, we've had a number of questions from golf course superintendents and product distributors about its effectiveness against turfgrass diseases. This year, we evaluated a mixture of Civitas + Civitas Harmonizer for control of brown patch and dollar spot on creeping bentgrass putting greens. So far, the results are promising.

The mixture of Civitas + Harmonizer was applied every 14 days beginning prior to the onset of disease symptoms. Industry standard fungicide treatments were included in each study: Heritage 50WG (0.2 oz every 14 days) in the brown patch study and Banner Maxx + Daconil Ultrex (2 fl oz + 3 oz every 14 days) in the dollar spot trial. The incidence of each disease was assessed periodically during periods of activity.

Civitas + Harmonizer provided good suppression of both diseases. Brown patch incidence was maintained at or below 5% of the turf surface area throughout the study, even under intense disease pressure in late July. Dollar spot incidence was significantly reduced throughout the season, reaching a maximum of 36 spots per plot in plots treated with Civitas + Harmonizer as compared to 160 spots in untreated plots.

The bottom line - Civitas showed good activity against brown patch and dollar spot in North Carolina in 2009. While it did not always provide acceptable levels of control alone, it should prove to be a useful tool for disease management as part of an integrated program.

A few words about the active ingredient in Civitas, which is a type of mineral oil, also commonly referred to as 'horticultural oil'. Horticultural oils have been used for disease and insect control in a number of crops for many years. These products have direct fungicidal and insecticidal activity, and are highly desirable in organic farming due to their safety and short residual in the environment.

Suncor, formerly known as Petro Canada, also claims that Civitas works by inducing systemic resistance in the plant. However, the research supporting this claim has not yet been published.

Leaf spot look-a-likes

A brief reminder to practitioners and agronomists that there are other late-summer leaf spot diseases of perennial ryegrass besides grey leaf spot. I recently observed a case in central PA in which a landscaper suspected grey leaf spot was taking out his newly-seeded perennial ryegrass. In fact, the disease turned out to be a different leaf spot disease. The spores appeared similar to descriptions of Drechslera siccans. For the record…..I was fooled as well. I could have sworn it was gray leaf spot when I looked at the turf in the field. When garden-variety leaf spot diseases get rolling on susceptible hosts during extended periods of high humidity, they can resemble early stage symptoms of grey leaf spot. Some common leaf spot diseases of perennial ryegrass include net blotch and leaf blight (Pyrenophora dictyoides (sometimes referred to as Drechslera dictyoides); Leaf spot, leaf blight, and foot rot (Drechslera siccans), and leaf blight and crown rot (Drechslera catenaria). Only your diagnostician….using a microscope…..knows for sure. For riveting reading, see the chapter on Leaf spots, leaf blights, and crown rots in Fungal Diseases of Amenity Turf Grasses by Smith et al. (1989 edition).

localized dry spot

Tribute to golf course dogs:

I am going to start this week by stating that golf course dogs are some of the best dogs around. I met another one yesterday who was the sweetest thing, a black lab. I think dogs love riding in golf course utility carts even more than they like riding around in pickup trucks. I'm not the only one smitten. I met a superintendent once where the dog was "technically, an employee of the parks department" for chasing geese. I think he was pretty taken with her, because he said that if he changed jobs, the dog might mysteriously disappear with him.

Okay, onto more serious matters.

Localized dry spot:

I had a putting green sample come in the other day where the turf was wilty. There were 4 cup-cutter plugs. When I picked up the first one, I noticed that the sand felt absolutely powder-dry on my fingers. This can indicate hydrophobic soil (water-repellent soil), otherwise called localized dry spot (LDS).

I did the old trick of placing some water drops on the soil and seeing if they wicked in. They did NOT wick in—they just sat there. As I read online somewhere, putting water droplets on normal soil is like putting it on normal paper—the drops get wicked in. Putting droplets on hydrophobic soil is like putting them on wax paper—the drops just sit there beaded up.

I examined the other 3 plugs. One was fine—the sand felt wet, and the water drops wicked in fast. With the other two plugs, parts of the profile were okay, but parts were hydrophobic. Hydrophobic conditions are usually in the top one inch of the soil, but it can be variable. In one plug, the top 1-inch was fine and the lower 1-2 inch was hydrophobic. One of the photos below shows drops beading up in the 1-2 inch range, whereas drops applied to the upper 1-inch wicked in.

LDS has been associated with the decomposition of organic matter, where the sand becomes coated with hydrophobic molecules. This been associated with fungal growth—some fungi produce and secrete hydrophobic chemicals. In particular, fairy ring fungi can produce hydrophobic chemicals, leading to the most damaging types of necrotic rings, but LDS is not always associated with fairy rings. This particular green did have some fairy ring issues, but NOT in the sites where the plugs were taken. There could be a correlation, but it is hard to say.

Wetting agents can help to move water into hydrophobic areas and to evenly distribute the moisture. Be careful, though, as some products can cause phytotoxicity under some conditions. Read the label carefully.

Water droplets wicked in on top, but not in the 1-2 inch range

3 drops sit there, not wicking in:

Snow mold:

I was glad to see Jim's postings about snow mold. As a Wisconsin native, I'm familiar with the regions where he's doing his work. In fact, while visiting my parents in March (they live in Madison, WI, not too far from the turf research center and the University Ridge course where Jim does some work) I stumbled across some snow mold. See, there's a hiking trail that runs through the woods at U Ridge and connects with a regional trail called the Ice Age trail. My parents and I were having a lovely walk, then I got distracted by the snow mold and couldn't help but stop, hunt for sclerotia, then teach my mom and dad to hunt for sclerotia.

Then, we came out of the woods and I found some guys spraying. I strolled over and said, "So, what are you guys spraying?" I could see the look of skepticism in his eyes, and you can imagine his point of view. It's a little unusual to have a woman you've never met come walking out of the woods in March in Wisconsin and ask what you are spraying. So, I quickly followed with, "I'm a turf pathologist, and I know Jim Kerns." With introductions taken care of, I had a nice converation with the superintendent, Aron Hogden (Hi Aron, if you are reading this!)

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: 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.

Pythium Root Rot....Is it a disease or not?

Hot and wet weather during July and August typically brings outbreaks of Pythium root rot on creeping bentgrass and bermudagrass putting greens in the Southeastern United States. Symptoms of this disease usually appear as a yellow to orange, irregular dieback that is most severe in poorly drained or stressed areas. In some cases, however, Pythium root rot can develop in distinct spots and patches. These patches may be yellow, orange, or even purple in color.

Pythium root rot requires wet soils in order to develop, either from poor drainage, over-irrigation, or frequent rainfall. In fact, some pathologists argue that Pythium root rot isn't a real disease; they believe that the saturated soils are killing the turf and that the Pythium is simply colonizing dead roots. It's a 'chicken and the egg' type argument - no one knows for sure which came first.

I tend to believe that Pythium root rot is a real disease, simply because curative fungicide applications help to stop the problem and encourage turf recovery. That being said, if you have chronic problems with Pythium root rot, the only effective way to manage this disease long term is to improve soil drainage. All of the fungicides in the world will not provide adequate control if the soil is continuously saturated.

From the descriptions above, it is clear that Pythium root rot symptoms are highly variable and can be confused many other problems. Because of this, it is almost impossible to definitively diagnose this disease in the field. Curative fungicide programs for Pythium root rot are expensive, so a misdiagnosis can be costly. If you suspect that you have Pythium root rot, send a sample to a diagnostic lab for confirmation.

Few fungicides are labeled for Pythium root rot control, and there is virtually no scientific data regarding their effectiveness. For preventive applications, applications of mefanoxam, fosetyl-Al, or propamocarb every 14 to 21 days are recommended. An occasional application of ethazole is never a bad idea, especially during periods of wet weather.

For curative applications, I recommend an application of ethazole to provide quick knock-down of the disease, followed a few days later with a mefanoxam application. This is a program that I 'borrowed' from Bruce Martin at Clemson several years ago, and it works like a charm.

To minimize the potential for foliar burn, ethazole must be watered-in immediately after application with at least 1/8” of water. Applications of mefanoxam or propamocarb should also be watered-in, but fosetyl-Al should be applied to the foliage for best results.

For more information about Pythium root rot, please refer to TurfFiles.

New Design...Same Old Problems

If you have visited the Turf Disease blog in the past, then you will notice that the layout and overall look has changed. A few of the things that are new include:

1. Information buttons (top right): These buttons serve various purposes, but mainly allow you to access the blog by RSS subscribtion or via twitter, view disease images on our new flickr Turf Disease group, or share this information with others through Digg It, Stumble, and Technorati.

2. Search bar (top right): A search bar has been added that allows you to search the site for any topic that you may be interested in.

3. Navigation buttons (bottom left of header): We have added navigation buttons to help you select the content that is appropriate for you. These buttons include links to the home page and to each regional update section (NE = Northeast; SE = Southeast, etc).

4. Image Gallery: Perhaps the most useful addition is the image gallery link which contains various disease symptoms and pathogen signs that are used for identification purposes. We are contstantly working to increase the number of images in the gallery and will add more diseases as photos become availabe.

5. Disease Poll (right column): In an attempt to get the superintendents more involved in the blog, we will periodically post a poll to find out what troubles most are seeing in the field each week or other questions related to turfgrass disease management. Results of the poll are presented in real-time and this gives everyone some indication of what others may be seeing.

OK, as for diseases in the Northeast:

As you might expect, the warm weather and periodic rains are creating conditions favorable for your typical summer time diseases. Brown patch and Pythium are high on the list of potential problems in the field. While others may have seen summer patch for the several weeks, the first case that I had seen all year was last week in Pittsburgh. Also active in the Pittsburgh region was dollar spot and leaf spot.

Following a visit to the Buffalo area, last week was met with some cool morning temperatures and disease activity was relatively low. The only issues noticed was some dollar spot activity in the rough. The 10-day forecast has low and high daily temperatures of 60 and 80, respectively for that region. Throughout much of the Mid-Atlantic and Northeast, temperatures run a steady gradient from the upper 80s-90F in the Maryland region to the upper 70's-80F in Portland, ME. Along with these higher temperatures is the threat of precipitation which should bring along some serious disease pressure as we head into the home stretch of the season.

KEEP in mind that the threat of rain that can disrupt your ability to make preventive or curative applications should be monitored. Your window of opportunity to target serious diseases throughout August may be short and you should take advantage of any chance you get to take action.

Kansas field day, plant path conference: turf&donuts


Thanks to everyone who participated in the KSU Turf Field Day in Wichita yesterday. The JC Pair Hort Center was looking fantastic thanks to Dr. Jason Griffin, his staff, and many volunteers. Though it was sprinkling, we were still able to move everyone through the 8 stops. The lightning was menacing by the end and I was happy to move inside and out of danger for lunch--Apparently my hair was sticking up due to static in the air so I was feeling particularly vulnerable. Unfortunately, due to the rain, I didn’t take my camera out to take photos at the event but I saw a few others snapping pics and maybe I can include those later.

As I mentioned at field day, my “top 5” list of plant problems (turf & ornamental) so far in 2009 are:

* root problems due to saturated soils (all plants, from turf to trees to flowers to vegetables)
* brown patch in turf
* cedar apple rusts
* pine problems in general
* Pythium blight in turf


It was actually pretty quiet while I was out of town over the last week. Mild weather has kept the usual stress issues in check. Today and the next few days will be hot, though, so I suspect a few calls will be coming next week.


Like my colleagues have mentioned this week, I spent Aug 1-5 at the national plant pathology conference. What do we do at these conferences (other than eat donuts)? It’s an opportunity for plant pathologists from across the US (and other nations) to get together and talk about recent and ongoing research and to discuss potential projects. People give presentations (usually 15 or 30 minutes) about their work, or they prepare posters (about 3 x 4 feet) to display research findings. The posters (nearly 900) are displayed in a big hall and authors are present at various times. That way, a viewer can stop by, read through a poster, then stop back and meet the author later to ask specific questions.

On the turf side, we had posters and presentations about a variety of topics. Here are some examples (of many):

*There are some new diseases popping up in Florida on warm-season grasses, as Jim mentioned. The researchers are trying to get a handle on the identification of the pathogen.

*There’s also a new leaf spot that has shown up in Mississippi and south Texas on bermudagrass and zoysia.

*Researchers in Arkansas showed some maps of large patch disease in zoysia. From the mapping at one site, it looks like aerification while disease is active definitely spread the disease around.

* Researchers in North Carolina (Lane’s group) are examining the influence of several fertility practices on spring dead spot in bermudagrass.

*On the more “basic” (lab) side of things, researchers at Ohio State are examining proteins that are secreted by the dollar spot fungus and how they might interact with plants at the cellular/molecular level.

That’s just a small sampling. I don’t have the energy right now to include more. Maybe we can explain more stuff later as we post more things to this blog.

Along with the formal presentations and posters, we had a turf meeting where we decided to try to arrange a symposium specifically about new Rhizoctonia diseases in turf for 2010. There are several groups around the US trying to characterize some new Rhizoc diseases in turf and there is a lot to talk about. At the 2010 planning meeting later in the week, I was pleased to discover that the ornamentals committee is also interested in some new Rhizocs in their commodities, and we will try to work with them to make a full day.

3) Donuts

Frank mentioned Voodoo Donuts in his posting. Try to match the pathologist from this blog with the donut(s) they consumed:


1) Frank Wong
2) Lane Tredway
3) Jim Kerns
4) John Kaminski
5) Megan Kennelly


A) pink bubble-gum flavor (this one was hard to choke down. The consumer started choking like they had a hairball)
B) glazed maple with big strips of bacon on top
C) chocolate cake doughnut covered with pink marshmallow glaze and peanut-butter filling
D) cream-filled with chocolate glaze
E) Triple chocolate (chocolate donut, chocolate glaze, covered with cocoa-puffs)
F) Chocolate with Butterfinger
G) Missed donut experience due to Chile trip (missed you, buddy)

Widespread Death & Destruction in Portland? No. Beer and Doughnuts? Por supuesto.

As you already know, many of the plant pathologists in the U.S. were in Portland this last week at the American Phytopathology Society meetings. As mentioned last week - Phil Harmon (Florida), Bruce Martin (Clemson) and Shanna Mazurek (North Dakota State) joined me on a quick tour of Portland Golf Club and Waverly Country Club on Saturday morning before the meeting. With temps in the 100s earlier in the week and a lot of wall to wall annual bluegrass - I was expecting to see nothing but brown up here. Arriving at PDX - I could see lots of dead grass from the air. However, on Saturday morning, I was very (pleasantly) surprised to see awesomely good course conditions at both Portland GC and Waverly CC. Thanks again to Forrest Goodling and John Alexander for the day and Gordon Kiyokawa for setting us up.

Forrest Goodling (Portland GC) - it was so hot recently that the thermometer couldn't even keep up with the 100+ degree weather.

The view of the club house at Portland GC - watching the weather and timely irrigation kept the Poa green during the hot hot heat.

Bruce, Shanna and Phil on the Willamette River - you can see what happened to a lot of grass in the PNW during the heat wave if it wasn't cared for.

John Alexander (Waverley CC) "schooling" Bruce on annual bluegrass and billbug damage.

John Alexander showing off some of the wickedly sloped (and fast) greens at Waverley.

Overall it was a great time seeing the courses and having Forrest and John share with us their experiences and expertise on turfgrass in Portland.

APS Annual Meeting (
As far as the meeting - I have to admit, I did not spend all of my time discussing turf while there. I was mainly wearing one of my other "hats" and focusing on new fungicides and fungicide resistance development in agricultural crops. I am hoping that Megan can give us a summary of some of the cool turf stuff (other than what Jim already mentioned yesterday about the work being done by Steve Kammerer and Phi Harmon) from the meeting.

Two things to note (1) just to make things even more complicated, the name 'Chrysorhiza' is going to be more frequently associated with 'Waitea' and 'brown ring patch' - but for good reason (2) I'm "officialy" going to be working more and more with the EPA in Washington DC on fungicide resistance issues starting in January as part of a fellowship and sabbatical in 2010. More to follow on both in the weeks to come.

Beer and Doughnuts
Portland definitely lived up to its reputation for beer and doughnuts on this trip. With over 100 microbreweries - I tried my best to sample as much of the local brew as possible. One night was even punctuated with a late night run to Voodoo Donuts - I wish I had some better pictures - but unfortunately - all my iphone camera could capture in the dark were images like the one below - but the picture does the situation justice. After a very very very long day of plant pathology talks and a few microbrews - my own world pretty much looked like what was captured by this camera.

Paul Koch (Univ. Wisconsin), Lane, and Damon Smith (Oklahoma State) out on a late night donut run. Missing: Brandon Horvath (Tennesee) holding a big pink box (of doughnuts).

I'm very lucky to be working with such a great group of turf pathologists from around the country, they really do play hard and work harder. Most importantly - it was a great meeting and opportunity to discuss turf disease issues from across the country.

Meanwhile, Back in Cali....
Naveen has definitely been using the bat-phone this week. She reports that the diagnostic lab is getting slammed in Riverside. Anthracnose and heat stress are very common on cool season turf. Root infecting diseases like Kikuyugrass/Bermudagrass decline and soil diseases like fairy ring are also showing up because of the effects of summer stress. I think the blast of heat we had in a few locations is catcing up with us.

Weather wise - it's definitey cooled down this week (no Pythium alert outside of Coachella), but still expect to see the typical summer diseases inland and dollar spot/brown ring patch on the very moderate coastal locations (70s-80s).

Signing off from Top-Pot Doughnuts in Seattle (that's another story),

- Frank

Coolest July on Record!

Well the big news from the Midwest is we just experienced the coolest July on record! I guess you can imagine that there is not a lot of disease activity. Dollar spot is progressing, but very slowly. Even at one particular site in Milwaukee that is usually a petri plate for dollar spot, the disease has been very slow to develop.

We have had some brown ring patch come through the lab recently and most people in the Midwest are able to clean that disease up with an application of Endorse or Prostar. Dr. Frank Wong has also shown that applications of nitrogen fertilizers also help to alleviate brown ring patch symptoms.

This post will be a little short because I have just returned from Portland where I attended the American Phytopathological Society meetings. Another fantastic meeting! I will let Frank elaborate on the fun sites :)! There were some excellent talks and posters. One talk I thoroughly enjoyed was by Steve Kammerer who is at the University of Florida. I know we do not grow warm-season grasses, but nonetheless Steve and Dr. Phil Harmon may be instramental in renaming or changing Rhizoctonia classification. Great job guys. For those growing warm-season grasses and are struggling with something a little weird, you might want to get in touch with Dr. Harmon or Steve.

One final note, this weekend is projected to be quite warm in the Midwest, so if you have not sprayed for dollar spot in a while tomorrow or Friday may be a good time.

Pythium, algae, brown patch, flooding and more

I returned from the International Turfgrass Society meetings on Friday afternoon and was greeted to a slew of new diseases in the region. At the research facility, algae and brown patch were taking off due to the recent rains and high temperatures. The recent rains were not without their own problems as it caused major flooding at various golf courses in the region. Most notably, Merion Golf Club had many bunkers wash out and even had holes under water for a period of time (Image of hole #11 fairway and green, courtesy Matt Shaffer). Also hanging on in many regions is the Type II fairy ring species on both putting greens and fairways. I have yet to see these rings collapse in the Northeast, but it is likely that some superintendents are dealing with more severe cases.

Dr. Landschoot indicated that Pythium blight was also active on his fine leaf fescue variety trials. Although I hadn't seen any Pythium around the facility, I did notice that half of my Kentucky bluegrass lawn was wiped out on the side of my house. This area receives little light or air movement and has a swale that carries the water from about 10 properties away from entering my basement!

Overall, I would say that this summer has been a cake walk as far as disease and heat problems are concerned. Although we are not completely out of the woods, we are getting close.

On the lookout...I have not heard any reports of gray leaf spot yet, but this is one disease that is likely just around the corner and preventive treatments should now be close or in place already depending on your location.

Do you have anything happening at your course worth sharing? If so, feel free to add your story to the comments section or send images to be included in a future posting!

OH! I almost forgot, everyone keep an eye out for Frank Wong's posting this week from the American Phytopathology Society Meetings in Portland. I hear they are seeing some interesting things in the streets of Portland this week!
Related Posts with Thumbnails