Yellow Patch Attacks! Lesson Learned.

This summer I set out a disease management plan aimed at controlling Fusarium Patch with as little traditional pesticides as possible. So far this plan has been very successful at controlling M. nivale but in the past 2 weeks I have been caught off guard by another disease, R. cerealis or yellow patch or cool season brown patch or, or or or etc.

This is typically the worst that I have seen yellow patch in
previous years.

Historically R. cerealis or yellow patch has never been a disease of concern for me. Last year I wrote a post outlining how I have never had to do anything for this disease on my greens ever. Since writing that post I have learned a lot about disease management. While the message remains the same my experience has changed quite a lot. When I wrote that post I was still regularly using traditional pesticides as needed on my putting greens. I was using a lot less than in previous years but I was nowhere near the lack of pesticide use that I am at today. Since May I have sprayed 2 fungicide apps to my greens for fusarium, 3 greens have received no pesticides to date. I also did a small spot application last week to two of my greens for fusarium. This does not include regular Civitas and phosphite applications. It has been 2 months since my last traditional pesticide application.

The worst of the R. cerealis on my putting greens. Full shade.

I think the destruction caused by the R. cerealis to my putting greens has been so bad for two reasons. The first is the lack of pesticide use and the second is my fusarium management plan.

In previous years the rather regular application of broad spectrum fungicides probably provided a level of control for the R. cerealis even though my intended target was M. nivale. This is one of the problems with broad spectrum products and also one of the benefits. As the fusarium was much more prevalent and destructive than the yellow patch and also occurred under the same environmental conditions I never had a problem with the yellow patch. With the success of my cultural control and organic pesticide plan I am seeing yellow patch progress to a destructive phase that I have never seen before.

The second reason for this outbreak is my Fusarium Management Plan. The biggest flaw in this plan that I failed to account for any other disease that I might encounter. The reason I made this mistake is that I had never in 12 years ever encountered another fungal pathogen this time of year! This is something that I think a lot of other turf managers fail to realize about pesticide reduction. In the past, through the regular use of pesticides, we have covered up a lot of the lesser diseases while combating the ultra destructive ones. So while attempting to further reduce my pesticide use I have actually not made any difference this fall as other diseases that I didn't manage for popped up. My bad!

Disease symptoms are much less sever in areas with little to no shade.

Part of my fusarium plan was to limit nitrogen applications in the fall. In retrospect I may have gone a little too far this fall. Great results for fusarium, poor results for yellow patch. Literature suggests that lower nitrogen levels can increase the amount of yellow patch in turf. Nitrogen applications after the turf has stopped growing is often recommended. This suggests another benefit of dormant nitrogen applications, something that I have not yet done. Now that my turf has finally slowed down in growth (a month later than normal) I can apply some N and hopefully reduce the level of destruction come spring. We will see...

Next year I will have a better grasp on my thatch issues as well as this season I did not have any means of topdressing my greens which should reduce this disease a bit.

So lesson learned and I hope it won't end up being a tough lesson as the winter progresses. For the most part damage is not extremely widespread and a corrective fungicide application should hopefully help. As always I will be leaving some knock out trials for yellow patch to see just how bad this disease turns out to be. As it is winter having poor quality greens isn't a huge issue so it will be interesting to see how the untreated areas end up in the spring! So if you are attempting to reduce your pesticide use be sure to include any other potential threats in your plans even though they haven't historically been a problem! Don't just manage for your usual main pest. My hope is that others will learn from my mistake on this one.

Hello Mr. Newt!

Roughskin Newt Nov 15 9th green

 Yesterday while inspecting my greens I came across this Roughskin Newt (Tarichia granulosa). In recent months I have seen a noticeable increase in the number of newt or salamander sightings on the putting greens at my course. This is the fifth salamander sighting since September.

I have always made mental note of newt sightings on the course simply because they are quite rare. I can only remember about 4 or 5 sightings in 12 years before this September.

Salamanders are considered to be an indicator species as they are extremely sensitive to environmental changes or pollution. They basically breathe and drink through their skin. Where human skin is one of our greatest defense mechanisms, amphibians will absorb anything they come in contact with through their skin. Many also spend part of their life cycle in aquatic environments and terrestrial environments which means that any pollution in either will drastically affect them. They also aren't affected much by predators as they are extremely toxic if ingested. They give a really good indication of the ecosystem health as a whole! For more information on amphibians check out the BC Frogwatch Page .

Oct 28 Upper practice green.

Recently I have started to record any salamander or frog sightings and will be instructing my crew to notify me when they make the sightings as well. I have inserted a visual inspection of the greens before mowing or rolling into the employee procedure manual and have also added a cup inspection before replacing a plug in an old hole. I have found 2 of these guys in old holes. This data gives me a really good idea of the health of the environment on the golf course.

A hot topic among the course membership is the fact that we are required to leave any trees that we cut down in the bush. Most people see this as wasteful. These newts are exactly the reason why we are required to do this. Many salamander species live in old rotten logs and if we continually clean the forest around the golf course we essentially remove salamander habitat.

In the end the fact that I am seeing more and more sensitive species on the golf course only confirms that the decisions I have made over that past few years have been for the better. With all of the negative press about pesticide use lately it is hard not to feel that as a golf course superintendent that I am destroying the environment. Well you know what naysayers!? I am not and I have proof!

Fall Disease Update--

The leaves are on the ground now so I guess it's safe to say fall has finally arrived. We saw a very extended summer that lasted well into October. The extreme dry conditions we faced in September were very interesting to say the least. I learned a great deal about both Fusarium and Dollar Spot and the conditions that favour these fungal organisms.

Early September saw the overnight temperatures finally start to drop down to reasonable levels. My original Fall disease management plan was put in jeopardy in early September due to a sprayer breakdown. I'm not sure if it was a coincidence or what but about a week after stopping my disease management program Fusarium started to show up on a few of my greens. It was in the usual spots at first but quickly spread out on all but 5 of our 12 greens. The greens where it wasn't located were the greens that received the most sun which wasn't surprising. The first signs of the fusarium showed up on the 5th of September but I was able to hold off a Fungicide spray until the 25th as the fusarium was very slow growing and not very aggressive. For the most part the turf was still able to outgrow the disease on my putting greens.

It's important to note that in my writing I am not considering Civitas as a fungicide even though it is registered as one. It doesn't act directly on the fungus but stimulates the plant's natural defence systems. I still apply it according to label rates and all that but the more I use the product the more I am starting to realize all the benefits it has to offer. I was putting Civitas down weekly at 1/4 label rates or about 0.125 ml Civitas/100m2.

Knock-out Trial

So on the 25th I applied Triton, a group 3 DMI to the affected greens at the label rate. In the past I had very poor success with this product and the product that I had in stock was leftover from a previous application the year before that had almost no impact at all on the Fusarium. What was interesting was that this product coupled with Civitas produced amazing results. A day after application there was no sign of mycelium where the day before the greens were fuzzy white! I was seeing curative results from a product that in the past I hadn't seen any results at all from. Of course there are other factors such as the weather, and the raise in HOC the week before but overall I was amazed.

I put down some knock out trials as usual to see how the untreated areas would manage. So far every untreated plot has fully recovered from any damage that might have occurred  All in all there was virtually no damage on any of the plots. You might ask why I applied the Triton in the first place then? Well when you see disease like the following picture on the entire green you cannot afford for it to get any more aggressive.

Today it has been 44 days since the Triton application and the disease level is still very low. Since that time I have put out 3 applications of Civitas.

Sept 30 Civitas @ .125ml/100m2
Oct 10 Civitas @ .250ml/100m2
Nov 5 Civitas @ .125ml/100m2

I have been experimenting with the timing of the Civitas applications a bit. I am applying it more on a growth potential model and less on a period of time model. Knowing exactly what kind of growth rates and vigour I can expect from the turf allows me to make better decisions about application rates and timing. In mid Oct we were experiencing very dry, and cool temperatures which brought the growth rates down significantly. For this reason I applied a heavier rate of Civitas but stretched the next application out as the turf really wasn't growing and I wasn't removing any of the product through mowing. In Oct I cut the greens 6 times where in the first week of Nov I have already had to cut the greens 4 times due to the warmer wetter conditions. The lighter application in early Nov was due to the fact that I am again mowing like a mad man and would more than likely have to apply another application in a few weeks.

Fuzzy white mycelium in Sept, my worst nightmare!

Rolling! Well my great intentions of rolling all through the winter stopped on Oct 12 due to the intense deluge of rain! Since that time the conditions have just been too wet to roll especially on some of our hillier holes. It was so wet in places that even my 4wd mowers couldn't mow. Now that the precipitation has slowed down a bit I will resume rolling regularly as conditions permit. So far this fall I haven't seen any significant difference in disease pressure on my trial green but for the most part disease pressure has been very low.

The crazy weather this fall taught me a few things about the two most important disease we face, Dollar spot and Fusarium. In the past people have always blamed Fusarium on the wet conditions. What I saw this September showed me that this wasn't necessarily the case, at least if you are concerned with rain. We saw the driest September in recorded history this year and sure enough as soon as the overnight temperatures started to dip below 10C fusarium showed up. What I learned is that Fusarium incidence is really more dependant on temperatures and less so on moisture. Of course standing moisture (dew) and excessively wet conditions don't help but my observations were that infection still occurred in the absence of rain.  It was especially bad in areas that were shaded (big surprise eh?).

Is he growing grass or Dollar spot?

Dollar spot was completely the opposite. I was always more concerned about the temperature than moisture with this disease. Turns out I was wrong again. The dollar spot severity in September was like nothing I had ever seen before, especially on fairways. We have a very difficult time keeping our fairways moist as we don't use any wetting agents and the areas that were the driest were the hardest hit. You could literally see the dollar spot from hundreds of yards away!

Compare treated and untreated

Yellow Patch! On the greens that didn't receive the Triton application in Sept the yellow patch has been crazy! I have always seen quite a bit of this disease but nothing like what I am seeing right now. These greens haven't received any traditional pesticides since May and it is really starting to show! I could be the first superintendent in history to actually worry about yellow patch!

Lots of yellow patch on greens that haven't been treated with traditional
fungicides.

It is really cool to see on the few greens that get the most sun how little disease there really is and it just reinforces to me the importance of providing full sun to the putting greens if you want to reduce your pesticide use. If all my greens had as much sun as my 6th green I could easily get by with Civitas alone with maybe one application of a traditional pesticide in the early spring. It is really too bad that trees have been included as part of the golf course design especially around the putting greens. It is really hard to convince everyone that they need to be removed. Sadly this is the best solution.

Here are a few videos I shot on Nov 08 around 11am showing the current disease conditions on my putting greens.

Hole 1:

Hole 3:

Hole 6:

Civitas and Dew

Recently there has been a lot of discussion about a new product in the Canadian turf industry, Civitas. Aside from all of the known benefits some superintendents (including myself) have noticed a slight reduction in dew on our greens.

In previous years we had always used a dew whip or drag on days where there was a heavy dew. We would either drag before the green mower or would only drag on days when we didn't cut the greens. This year I have yet to see the need to drag the dew off even once on my putting greens. This even 1 month post application at the 0.250ml/100m2 rate.

Areas that haven't been treated on my course have had a lot of dew compared to the greens. This is hard to compare, though, as longer turf tends to hold more dew naturally than the close cut putting green turf.

Early this week I applied 2 different Civitas rates to my fairway nursery to see if there was any difference in the dew formation. So far it appears to the naked eye that there is a difference but it's hard to tell if this is just related to the colour of the harmonizer dye playing a trick on the eye. I haven't figured out how I can quantify the amount of dew easily on these trial areas yet. My next application will be on one of my practice greens to compare.

0.125 Civitas on the left and .250 Civitas on the right. Nothing
in the middle.

Although I have a hunch that it is only an optical illusion I can say that there is much less, if any, rooster tails on golf balls when rolled on un-whipped greens. Perhaps this could be a better judge on how much dew is present. Who knows?

Aside from the playability benefit of having less dew on the greens this could be another reason why many other turf managers and myself are seeing such great results from Civitas. Less dew usually means less disease!

There is still dew present but I think it might be less

So for now it could just be that the dye is playing a trick on me but then again who knows. I really look forward to any formal research on this phenomenon.