Waitea Patch trials give me the Hives

Let's try something different this week!

Shot on an iPhone4 and edited with iMovie.

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....

Get Ready for Anthracnose in the West

Sadly, Farrah Fawcett passed away from cancer today at age 62. I bet you that just about anyone who was a teen in the 1970s had a poster (like the one to the left) in their room.

We probably invoke her name at least a dozen times a week here at UCR since we work in Fawcett Laboratory. Often, when explaining where to send samples, we tell people that: "it's Fawcett Lab, as in Farrah Fawcett" - which often goes right over the heads of those superintendents in their early- and mid-20s. For that matter, many John Holmes references - in relation to optimal root length - also go over those guy's heads too. I have got to stop using 70s-pop culture references so frequently here in our lab.


Anthracnose Management
Here in the west, anthracnose is starting to pop up more frequently in the UC Riverside diagnostic lab. It could signal the start of the anthracnose season already. Although anthracnose can pop up on just about any cool season turf species, it's impact is very different on different species being used for different purposes on the course.

For perennial ryegrass, the presence of anthracnose often signals low fertility, heat and drought stress. Here, anthracnose is usually just a secondary pathogen affecting stressed turf. It usually does not warrant control directly, but does often indicate that cultural conditions need improvement in these areas.

On creeping bentgrass, we typically see anthracnose on greens that are "lean and mean", especially when there is high humidity and overcast days. Again, in these cases, anthracnose is usually not the primary cause of damage but does signal that fertility needs to be increased and plant stress reduced. Typically, shutting anthracnose down with a fungicide application or two followed by increasing the fertility will solve the issue.

On annual bluegrass though, anthracnose is a real killer because its often the disease that puts the nail in the coffin for Poa greens.

Check out our presentation on chemical control options for anthracnose here: http://www.turfpathology.ucr.edu/Downloads/anthracnose_chemical_control.pdf

as well as the cultural management practices for anthracnose research being spearheaded by the group at Rutgers
http://www.turf.rutgers.edu/research/usga-anthracnose.pdf

Sucessful anthracnose management on annual bluegrass greens in the West should combine cultural practices like adequate nitrogen fertility and water management with a sound preventive fungicide program.

With regard to fungicides for anthracnose - there are plenty of ways to skin a cat, but in a nutshell - here's what has been effective for us in trials conducted over the past few years.

Early season preventive DMI applications (especially Banner MAXX) should be initiated before soil temperatures exceed 70F (65-68F is usually a good starting place).

Chlorothalonil fungicides, Medallion and Endorse are good choices for control when air temps are high and the risk of negative PGR effects of the DMI-fungicides are present (see Lane's recent entry on the DMIs). These should be applied at 14-day intervals in the summer.

Chipco Signature can be tank mixed with the fungicides listed above for added control and stress reduction. Although the mechanism for stress reduction provided by the combination of pigment and fosetyl-Al in Chipco Signature is still not fully understood, I'm going with the theory that it's "sunblock for Poa". Although results from trials in the east have shown a direct effect of phosphonate type fungicides on anthracnose - our trial results from California have shown that Chipco Signature applied by itself isn't very effective versus anthracnose and needs a good partner to maximize the effectiveness of the tank mix application.

Finally - I don't mean to kick a dead horse, but QoI and benzmidazole resistance appear to be pretty common for anthracnose in areas that have used them exensively for anthracnose control. Monthly applications of Heritage or Insignia are still very important for summer patch control in the summer, but don't rely on them exclusively for anthracnose control.

In Other News...
Brown Ring (Waitea) Patch was reported from Minnesota and diagnosed from Montanta this week. It sounds like this disease is continuing to pop up throughout many places in the U.S.

Signing Off from the Left Coast!

Brown Ring Patch or Yellow Patch?

Disease activity is relatively slow at this point, but there are some reasons to believe that this will change soon. So far, several cases of brown ring patch and yellow patch (i.e., cool temperature brown patch) have been identified from Pennsylvania to parts of New England. A quick way to distinguish between these two diseases is to incubate a cup-cutter plug in a tuperware container overnight. If mycelium is present in the morning, you are likely dealing with brown ring patch as yellow patch does not produce much visible mycelium.

Main areas of interest throughout the region have focused on annual bluegrass seedhead suppression and the application of early season fungicides for the control of dollar spot or fairy ring. In situations where chronic disease activity occurs, these early season fungicide applications have been shown to reduce the severity of each disease later in the year.

If you are in the Northeast and experiencing other disease problems, feel free to let us know in the comments section.