Monday, 17 December 2012

Nitrogen Rates and Timing Comparison

With all my talk about nitrogen lately I thought it would be cool to compare how different methods of nitrogen fertilization would look. As nitrogen is one of the few things that if we add more the plant will use more the differences in application rates can have a varied affect on plant health and response. The following chart illustrates the same amount of nitrogen applied per season but at different rates at different times of the growing season.


Now we know that the blue line is what the plant actually needs so if the lines from the other application methods are above the blue line you are essentially over applying nitrogen and if the lines are below the blue line you are under applying. Over applying and under applying both have their purpose in turfgrass management but they also carry consequences.

I read somewhere that a visual turf response can be seen at nitrogen rates as high as 6Kg N/100m2 per season! Currently my rates are about 1.4Kg N/100m2 per season. So essentially I can see a difference if I applied 4.3X as much nitrogen as the GP model suggests for my climate. I can then use this data to compare the difference between the different fertilization strategies to see exactly how my turf is able to use the nitrogen I am applying. The following chart compares the different nitrogen use rates between the GP method and the constant rate method and also shows the difference in multiples of the required amount of N.

rates are in Kg N/100m2
So essentially I could expect to see a difference in growth response if I applied up to 4.3x as much N as was actually required by the plant. Looking at the column to the far right it shows that the constant method would be applying as much as 9.6X as much fertilizer as was required by the turf in March. It isn't until June that this method stops over applying nitrogen and in July and August I am applying half as much nitrogen as is required by the turf. No wonder I was getting hammered with disease!

What are the consequences of these practices? Applying more nitrogen than is required is wasteful and can't be good for the environment either. Under applying in the summer can only make your challenges more difficult.

This brings up another problem that I see with nitrogen fertility in the industry right now. With all of the different slow release nitrogen formulations how can you be assured that you are getting the release that is required. Each different product releases differently under different temperatures, soil moisture and particle sizes. Changes in the weather can really make a big difference in what you apply and what is made available to the plant, especially in the long term. For this reason I use soluble nitrogen sources exclusively on my putting surfaces. On my fairways I have a little more room for error as I do not use pesticides on them anyway. By using Urea and Ammonium Sulphate I am able to have a better idea of what is actually available to my plant and eliminate a lot of guesswork when it comes to how much nitrogen my plant has. When it comes to the importance of nitrogen fertility on plant health I cannot afford to guess!

Having the power and the knowledge to use nitrogen to our advantage is a great tool! We have the ability to apply a bit extra when needed to increase growth a bit or to recover from damage. We also have the power to reduce rates to slow the growth down which requires less mowing, less diesel and makes for faster firmer playing surfaces. What we need to know is how far off from what is required our nitrogen applications are and what the potential consequences may be. Is filling in those holes a few days quicker really worth the cost associated with an extra fungicide application? Financially and environmentally? Is that half pound N application really going to be usable by your turfgrass with the current temperatures?

I encourage everyone to compare their methods of nitrogen fertility to the growth potential model to see how far off of the plant's actual needs you are. Applying half as much nitrogen as is required surely has to have it's consequences. It's nice to be able to adjust the rates but it is important to keep the adjustments reasonable to avoid any negative consequences  It is the responsible thing to do for your bottom line and the environment.






Equipment Use Record: Using a form to keep data consistent

One of the very first spreadsheets I made on Google docs was my equipment use record. This spreadsheet keeps track of all equipment use on the golf course and allows me to filter the data so I can intensely scrutinize every detail.

The basis for this spreadsheet and pretty much all of my other spreadsheets is the form. The benefit of using a form is that it allows you to keep the data consistent and easy to input into the spreadsheet. Consistent data is extremely important when you decide to filter and sort it out later on. Even the slightest difference such as an extra space can keep the record from working.

The first step is to create a new spreadsheet in Google drive or docs and name it accordingly. I call my sheet "PHGC Equipment Records". I use this naming scheme for all my spreadsheets to keep things consistent.

Once you have done that the next step is to create a form. Goto: Tools--> Create a Form

Creating a form takes a little forethought and careful planning. This is the tool that is used to collect all the data and it needs to be thorough, well thought out and clear and easy to use.

My form starts with a drop down list for who is submitting the record. Drop down lists allow you to keep submissions the same and easy to input. To add a drop down list first select the "Add item" button on the top left of the edit form panel. Then select the "Choose from a list". You can then add all the names of those who will be operating equipment. I start with those who operate the most frequently to make it easier on them.

The next drop down list is which machine the record is for. I don't have very much equipment so I use the model names for this. A larger operation would probably find it easier to assign a number to each piece of equipment to keep is easier to work with.

Next is the hour meter input field. This is where the operator inputs the hour meter reading after they are finished their task on a piece of equipment. This is very important information when scheduling maintenance procedures like oil changes and setups and reel grinding.

Next is another drop down list for different areas of the course. I have it broken down into Greens, Tees, Fairways, Approaches, Rough, Traps and Cart Paths. You could have this broken down into all the areas that you have your course organized in. Some courses mow their green and tee surrounds with a different mower than their rough so I would add Green Surrounds to the list in this instance.

Next up in the form is a list of check boxes to indicate which holes the work was performed. This is especially important if you plan on doing efficiency studies with this data as all parts of the course are different sizes and take different amounts of time to complete. The first selection in my check boxes is "All". This makes it easy for the person filling out the form. I have made this question mandatory as it is possible to not select a box unless this is required.

I also have another drop down box for circle cut directions. I like to alternate directions of circle cuts to avoid laying down the turf. This information shows up on my website and shows the operator the last direction the circle cut was performed in.

You can add many other things to the form such as fuel quantity, amount of grass clippings collected etc. But for now this is basically all that is required.

formdata sheet with a bunch of data entries
Once you have your form more or less complete you can close the window and return to your spreadsheet. Remember that you can always go back to the edit form option to add any additional data. Now that you are back in the spreadsheet you will notice that the top row of the first sheet has the headers that you named in your form. When you submit an entry into the form it will appear here. It also includes a nifty time stamp which indicates the exact time the entry was submitted! This is handy as it automatically keeps the date for you which is a pain to manually enter. I always name the sheet where the form data is submitted "formdata" to keep it simple. I don't like spaces or capitals in sheet names as it makes referencing them in the future a bit harder. The formdata sheet should be left alone and you should never manually add any data to this sheet. This is the data in it's raw form and from where you will pull specific filtered data from. If you make an error in submission of the data in the form this is where you will edit it. Remember, only edit existing entries otherwise it can cause all sorts of problems!



Now comes the complicated part, filtering the data to make sense of it all! This is the part that really helps if you are a spreadsheet wiz but I will try and explain it as best as I can. I will provide links to official Google help articles when required.




The easiest way to filter the data is to create a sheet for each individual piece of equipment. I have created one sheet for all equipment but the filtering formula is rather complex. Here I'll show it to you so you can believe me!

=iferror(if(and(B1="All",B2="All",F1="All"),filter(Formdata!A2:I,Formdata!A2:A>D1,Formdata!A2:A<D2),if(and(B1="All",not(B2="All"),not(F1="All")),filter(Formdata!A2:I,Formdata!A2:A>D1,Formdata!A2:A<D2,Formdata!B2:B=B2,Formdata!E2:E=F1),if(and(B1="All",B2="All",not(F1="All")),filter(Formdata!A2:I,Formdata!A2:A>D1,Formdata!A2:A<D2,Formdata!E2:E=F1),if(and(B1="All",not(B2="All"),F1="All"),filter(Formdata!A2:I,Formdata!A2:A>D1,Formdata!A2:A<D2,Formdata!B2:B=B2),if(and(not(B1="All"),not(B2="All"),not(F1="All")),filter(Formdata!A2:I,Formdata!A2:A>D1,Formdata!A2:A<D2,Formdata!C2:C=B1,Formdata!B2:B=B2,Formdata!E2:E=F1),if(and(not(B1="All"),not(B2="All"),F1="All"),filter(Formdata!A2:I,Formdata!A2:A>D1,Formdata!A2:A<D2,Formdata!C2:C=B1,Formdata!B2:B=B2),if(and(not(B1="All"),B2="All",F1="All"),filter(Formdata!A2:I,Formdata!A2:A>D1,Formdata!A2:A<D2,Formdata!C2:C=B1),if(and(not(B1="All"),B2="All",not(F1="All")),filter(Formdata!A2:I,Formdata!A2:A>D1,Formdata!A2:A<D2,Formdata!C2:C=B1,Formdata!E2:E=F1))))))))))


The reason this is so complicated is because I have created drop down lists that include the option "all". This significantly adds to the work required to filter the data!


Yep, that is all required to filter all the data according to operator, date, machine, and area of the course! With this formula I can sort a specific operator on a specific machine mowing a specific area of the course during a specific time frame. It is really cool to compare different operators to see who is getting the best efficiencies and who needs some pointers for improvement.


The formula required for one specific machine is much simpler: =filter(Formdata!A2:I,Formdata!C2:C=$A$2,Formdata!A2:A>$B$1,Formdata!A2:A<=$D$1)


So what you need to do is create a new sheet and name it according to the specific machine you want to see the data from.
Filtered sheet for my 3100 greens mower.


I then put the name of the machine up top somewhere as well as the start date you want to filter and the end date. It is important to keep the name of the machine in this cell exactly as it appears in the "formdata" sheet. Often I will submit an entry with that machine and copy/paste the name into this cell to keep it identical. In the cell for the end date I put =today()+1 which keeps the date in this cell current plus one day so that you can see the current day's entries.


I then add the headings found in the "formdata" sheet just below the dates as can be seen in the above image.


To filter out the data for the specific machine I use the filter function. Enter this function directly below the date heading. Your source array should be formdata!A2:A. The "!" tells the spreadsheet that the formdata is a sheet name and not a formula name. This will set the source for the entire A column in your formdata sheet and will automatically expand as you add entries to the form. If you put formdata!A2:A99 it will stop filtering after 99 entries which is bad. When filtering from a formdata sheet always keep the second part of the array open without a row number.


Your first array condition should be to look for and filter only data for the specific machine you want. This will look like formdata!C2:C=$A$1. The C2:C should be whatever column in the "formdata" sheet that contains the names of the equipment and the $A$1 should be the cell in the filtered sheet which contains the name of the machine you want to find and filter. The "quot; is to keep this cell reference the same if you copy the formula to another cell which we will be doing later.


The next array condition should make sure that the entries are for only after the selected date above. this will look like formdata!A2:A>$B$1. This will search the column A in the "formdata" sheet for any dates that are higher (>) than the start date in cell "B1" on your filtered data sheet. B1 should equal whatever cell you chose to be the start date entry.


The next array condition is the end date which looks like formdata!A2:A<=$D$1. The "<=" means less than or equal to an the D1 references the cell where you current date is entered.


That's it for your first column in your filtered sheet. If you used your $ signs properly you should be able to copy this formula to the right and the sheet will filter for each respective column.


Now that you have your first sheet made go to "form-->go to live form" and your form will appear. Enter a submission for you latest filtered equipment sheet and one for another equipment sheet. Now go back you your newly created sheet and you should only see the data for the equipment that you want to see. Cool!


Now if you want to create another sheet for another piece of equipment you can simply select your sheet at the bottom of the page and then select "Duplicate." This will create another identical sheet to the one you just created. Rename this sheet to the piece of equipment you want it to be for and change the name of the equipment in the cell on the top left of the sheet (A1). Just like that and this sheet will be filtering the data for only that piece of equipment!.


You can do this for every piece of equipment you have in your fleet!


Now that you have the basic filtering down you can further edit each page to get more information. I like to add up the total hours that the machine is used but unlike most spreadsheets you have to do this at the top of the sheet rather than the bottom. This is because this sheet will continue to get bigger and bigger automatically as entries are added. I use the "min" and "max" functions for this task. In the cell above the hours input column enter the following =max(D4:D)-min(D4:D). What this does is search the column D for the maximum number then subtracts the minimum number from that column to give you the total hours of use for the specified time frame. The D4:D in this example should reflect whichever column you are trying to find the total hours from.


To make this form more accessible to my staff I have created a staff website that is only accessible to my staff Google account on Google Sites. I have then created a page on the webpage for each form. To add a form to your website in you spreadsheet select "form--->embed form in a webpage..." This will give you some HTML code. Don't be alarmed. Just right click on the code and select copy. Now when you are editing your website go into HTML edit mode and paste the code into the site. This will insert the form into your website and allow your crew to access the form easily on any device with internet access. I have all my forms loaded into my iphone through my website. It doesn't require any fancy apps or programs. Just your simple web browser. What I really like about Google drive, sites and everything else is it easily allows you to adjust who has access to what through their "sharing" options. Almost everything can have its access rights changed.


Congratulations! You now have the starting point for a very powerful data collection tool. I have taken this way further than I have just described but with this collected and sorted data you can now manipulate it any way you want! This is a bit more work to set up than the old fashioned paper forms but it will save you tons of time in the end!


If anyone has any questions about this process please feel free to leave a comment! I would appreciate feedback about things that I could explain more clearly in future posts on the subject.
























Friday, 14 December 2012

Nitrogen, the Overlooked nutrient in IPM?

Got some time? This one might take a while!

A very big part of any IPM program is turfgrass nutrition and arguably the biggest part of turfgrass nutrition is nitrogen. Since starting out in the turf industry I have always struggled with how much nitrogen I needed to apply to keep my turf healthy. What even is healthy turf?

Is this turf healthy?
For me healthy turf is a playing surface that requires the least amount of inputs and money to achieve the desired playing conditions. To achieve healthy turf I start with the basics and work towards the more complicated stuff. There's not much point in focusing on the details if you don't have the major things in check. Obviously the major things you need to grow healthy turf are air, water and sunlight. After these things comes soil fertility or turfgrass nutrition.

I have always felt that nitrogen was the biggest part of turf nutrition but I had no real way of easily knowing what the turf required. The other required plant nutrients were easier for me to work with as soil tests painted a pretty clear picture of what I had in my soils. Nitrogen on the other hand is a bit trickier to test for and I always struggled to know exactly how much nitrogen I should be applying to keep my turf "healthy." Nitrogen is one of those things that you can apply to your turf and see immediate results a day later. There isn't much else out there that give the immediate and obvious results that nitrogen does (maybe iron) so this was my main focus when trying to combat turf diseases the past few years.

There is a lot of data out there about nitrogen rates and their effects on plant disease. Fusarium, for example, is much more prevalent when more than 1.8kg of nitrogen is applied to 100m2 per season. This was a great starting point for my nitrogen fertility program as fusarium was the most destructive and prevalent turf disease on my course. This number was a great starting point but it really didn't help me much. How much and how often? How did I know how much my specific plants needed this week vs next week.

It wasn't until recently that I came across the GP (growth potential) nitrogen use calculations which made it easy to calculate how much nitrogen your turf needed based on the climate for your specific site. AT LAST! A straightforward way for me to determine my turf nitrogen needs. I switched over to this way of fertilizing this past summer. At first I based my rates on monthly average temperatures but in talking with Dr. Micah Woods from the Asian Turfgrass Center he urged me to base my calculations on the next week's forecast. I thought "why not?" and made the switch. After all it only added about 2 minutes of extra work for me to determine this over my previous methods. This was a way for me to really fine tune my nitrogen fertility rates. This is all great but how does this tie into my IPM program and how do I practically use nitrogen to control disease?

What I am thinking is this. If we look at the "disease triangle" we can easily see that in order for there to be infection there needs to be the pathogen, the susceptible host and the favorable conditions for infection. The pathogens are always there, deal with it. We don't always have control over the environments but we can monitor it and forecast disease threats. In my climate my disease threats are mainly fungal in the forms of Fusarium Patch, Dollar Spot, and now Yellow Patch. When you look into these disease and the cultural practices that offer the most impact nitrogen fertility often comes up. This makes sense as it is the nutrient that has the greatest affect on plant health. Generally Fusarium is most damaging under high N fertility, Dollar spot and Yellow patch are most damaging under low N fertility. The problem with the way I used to fertilize is that I was guessing what the plant needed and inadvertently making these disease issues worse by doing so.

I was always taught that cool season turf sees increased growth in the spring and fall and during the warm summer months it saw a decrease in growth rate due to the warm temperatures. Well this was very true if you were managing cool season turf in California! Turns out this growth rate model doesn't apply to everywhere because, you guessed it, not all sites are the same. So what research was telling me is that in the spring I was to apply higher rates of N to kick start growth and to match the supposed high growth rates. This was during a time when the temperatures were the most favorable for fusarium attack. So I'm applying lots of N when lots of N promotes the most prevalent disease? This doesn't make sense. But again I was going off of what I was taught and attempting to use nitrogen to produce a "healthy" turfgrass plant. At least my intentions were good.

Again my problems were worsened in the summer. Research told me that I was to reduce my N rates in the summer as the turf growth rates were slower and didn't require as much. Again, the most prevalent disease in the summer temperatures in my climate was dollar spot. I was dealing my turf a double whammy on this one. Deficient nitrogen applications and increased dollar spot activity! No wonder we got smoked every summer!

Look! I found some dollar spot! This was the extent of the damage
on my putting greens this summer!
This year I had zero dollar spot on my greens and I didn't require any traditional pesticides to control it. Of course you could give the credit to rolling, phosphites or Civitas but I think that there was more at play than simply these "bandaid" practices and products. Their mode of action requires already healthy plants and all they do is boost or trigger the disease response. In the end it is still the plant that is doing the work and if you have unhealthy turf these products won't do much for you. My nitrogen rates on my putting greens were roughly double those of previous years and I had zero incidence of dollar spot.  Whoa, wait! Double! well that equated to a cost of about $120 for N this summer apposed to about $1200 in corrective pesticide applications in previous years. The math here is simple. Next year I plan on significantly reducing my use of Civitas and phosphites as I don't think it was necessary to produce "healthy" turf this summer.

The fairways had a "little" dollar spot!
My fairways were a different story. They were completely smoked, no, NUKED with dollar spot this summer. This year I made the switch from regular SCU apps to two larger UMAXX apps timed to provide higher amounts of N in the Spring and Fall and less N in the Summer. As could be expected I was hammered with fusarium on my fairways this spring and hammered with dollar spot this summer. No surprises here. The damage was unlike anything I had ever seen....ever! Next year I will either do one big app in last spring/early summer or will add some N into my wetting agent spray apps for the summer. Not sure yet.

This fall I made plans to combat fusarium but none of those included anything to do with nitrogen. When I look back, the biggest difference to my maintenance practices this year was nitrogen rates. This year I had virtually no issues with fusarium patch. A traditional pesticide application was made in late September but my knock out trials showed that this was unnecessary. Ask any of the other superintendents around here and you will hear about the "Fall from hell" as far a fusarium  is concerned. Not here it wasn't.

An interesting aside here about disease and shade. This year I broke my putting green soil tests into sunny and shady greens. Not surprisingly the sunny greens had significantly less nutrients in the soil due to the higher plant metabolism. The shady greens tested at almost double the amount of nitrogen as the sunny greens. Could this be a contributing factor in the disease development? Not only did I have more fusarium in shady spots but I also noticed less yellow patch and dollar spot on the shady greens. Yellow patch and Dollar spot were always the worst on my most sunny putting surfaces! I would really like to see a study comparing plots in shade and full sun with the same rates of N applied to both or rates applied based on the specific growing environments of each site for disease pressure. Would there be a difference? My greens in the sun have been running lean on nitrogen and my greens in the shade have excess nitrogen. Nitrogen is one of those things that if you apply more the plant will use more (to a point) so I wonder if this is having any effect on the disease?
G1689 are the sunny greens. Cool huh! Highlighted are deficiencies according to MLSN! That's right I got a calcium deficiency hahaha.
Not yet realizing the role of nitrogen in IPM I cut off my nitrogen supply in late October even though the GP formula suggested that it was required. This was a mistake as this self imposed nitrogen deficiency gave the home field advantage to the yellow patch! CRAP!

My GP fertilizer calculator takes seconds to use
Next year I plan on pushing my nitrogen fertility program further. I am toying with the idea of tweaking the rates based on the current disease threat. Where normally I would be fertilizing at 100% based on the forecast temperatures I could change this percentage based on different temperature ranges. For fusarium I would maybe run at 80% N or with dollar spot maybe 110%. I'm not sure the specifics but it is definitely something I am going to be playing around with next season. This is another reason to use soluble source of nitrogen so you can constantly tweak it. Slow release n sources rely more heavily on outside influences for their release and therefore give you much less control over what the plant is actually getting.

A good analogy is a carb on an engine. The throttle determines how much gas enters the engine. The throttle is the temperature and the gas is the nitrogen. In turf we cannot control the throttle so we must supply the right amount of fuel or nitrogen. We can tweak the carb to either run rich on fuel or lean on fuel. Depending on the air pressure we need to adjust this setting. In the world of turf, air pressure represents disease pressure. As the disease pressure changes we need to adjust the amount of fuel ever so slightly to make sure that the engine performs accordingly for that specific condition. In turf, just like the engine, there is no point in adding more fuel than the engine can use. Doing so only makes the engine perform poorly. In this case more does not equal better. All too often I hear of turf manager giving a good heavy N application to get things growing quick. Sure this works to a point but if the temps aren't there you are wasting your time and probably creating a bigger problem with the lush succulent conditions. Fusarium outbreak following aeration and heavy N app sound familiar? Wouldn't it make sense to "harden" the plant leading up to aeration to reduce turf injury then increase N rates following all the wear and tear?  Maybe I'm wrong and I'm living in a fantasy world but this is how I am starting to see things.

I know a lot of you will laugh and dismiss my rantings as nonsense but the fact is that for the most part we are guessing how much n our turf needs and how much n we supply to our turf has a very big impact on all aspects of the plant health. By spending more time and effort getting the N rates just right I think that we will be able to produce better turf for less money with little to no pesticides. Of course there will be times when outside intervention is necessary. By focusing on more complex "issues" and completely ignoring something as "simple" and important as nitrogen fertility I think you are creating more problems than you are solving. Part of a good IPM program is making sound management decisions based on science and fact and reducing any guesswork there might be. Let me know what you think.



Wednesday, 12 December 2012

Record Keeping

It's that time of year again. Many of us use the slow winter months to look over our records to analyze this past season and plan for next season. In order for this to work it is important to have good meaningful data. Good data comes from good data collections which can sometimes be a challenge. In the next few weeks I plan on sharing my experience with using Google docs for all of my operations record keeping the past few years and will give step by step instruction on how to setup good meaningful records that will allow you to easily analyze all parts of your operation.

A few years back I was searching for a good record keeping solution. The old way of keeping records on paper had very little use to me as it was clumsy and very difficult to easily analyze the data. For me there is no point of collecting data if it cannot be manipulated to tell a story or paint a picture. I came across many companies that offered record keeping software and tried a number of them out for demo periods. The problem I had with these software packages was that they were very expensive, time consuming to set up, and were not flexible enough for me to make the best use out of them. I needed something that would be tailored specifically to my operation.

Finally I got a computer in the shop and spreadsheets opened a whole new way of keeping track of my records. Data sorting was much easier and I was able to make sense from all that collected data. For me there was still something lacking. With this system I wasn't able to record data directly into the spreadsheet in the field. Data input was also a hassle and I found it very cumbersome (especially when I was busy). Often data collection and input was put off or forgotten about......until I came across a product from Google called Google Docs or Drive. The reasons I chose this service over the many other available options was that it was free, worked on both macs and pc, was accessible from any computer or device with internet access, had most if not more of the features that Microsoft's Excel offered and had the backing of a large company so I was assured that it would continue to remain in service for a long time.

My equipment use record is one of my most valuable records
Basically Google docs is a cloud based system where you can edit spreadsheets  documents or anything else all on a central server that is accessed over the internet. No crazy networks or servers to deal with, just the internet. Added to the ease of use  was the ability to input data directly into a spreadsheet using a form that can be accessed over the net. The possibilities were endless and I immediately went to work.
Knowing exactly what and where was applied is extremely useful

Over the past few years I have made hundreds of spreadsheets for record keeping where a few have stood the test of time and really helped me improve my operations on the golf course.

Over the next few weeks I plan on sharing how I put together my equipment use log, equipment maintenance log, spray record and fertilizer record. I will start very simple and will work up to more advanced spreadsheet work.

If this sounds of any interest to you I urge you to create a Google drive account now and start messing around with what it has to offer your operation.

Thursday, 6 December 2012

Yellow Patch 2 weeks later

Well it has been almost two weeks since my last post about yellow patch. Initially I was panicking due to the many unknowns that I was facing. I had never seen yellow patch (R. cerealis) damage turfgrass. Shortly after publishing that blog post I was inundated with information about the disease from other superintendents. Apparently I'm not the only one out there having difficulty with this disease on my greens!

 7th green Yellow Patch Nov 24
7th green Yellow Patch Dec 06, same location as above picture.
A fellow superintendent suggested to me that I try a nitrogen application. I immediately went out and sprayed an application of Ammonium sulfate at 0.05kg N/100m2 or about 9kg for all my putting greens or about $8 worth of product. This was basically the accumulated nitrogen needs for the turf for the winter months according the the growth potential calculations for my climate. If this proves to be a practical and effective means of control for this disease that would be great as an application of a pesticide runs about $600.
6th Green Nov 24
 Looking back at my nitrogen applications the last application was made on October 24 at about .01kgN/100m2. I had then stopped any further applications as it got quite cold in early November. In retrospect I think I should have applied the heavy "dormant" nitrogen application in late october no matter what the growth rates were doing. Maybe this would have helped my situation. In past years I had always applied nitrogen through the winter months as our climate is quite mild. This year I had reduced N applications significantly to try and combat the fusarium patch which I have been surprisingly successful in doing. Since the N application I have not seen any fusarium show up anywhere (not even one single spot actually!).
6th Green Dec 04
At the time of our discussion and my blog post I had no pesticides in stock. I ordered some as I had no clue if the nitrogen applications would make any difference especially considering the time of year. Well it has been two weeks now and I haven't been able to apply any pesticides to the infected greens. At first it was a shipping error and then heavy rains. Now it is a lack of water to fill my sprayer! I was able to spray some Iprodione on two of my greens but not the ones infected with the yellow patch due to wind. In either case I am now glad that I wasn't able to spray this green.
Incubated infected turf plug. Seems to be recovering.

Two weeks later it seems that the turf is starting to make a recovery. It has helped that the temperatures have risen a little this past week (average temp of about 6C). I am not only seeing signs of recovery on the sunny greens but also the shaded areas. Of course it is still very early and the winter hasn't even officially begun yet. I don't think I would have seen the results I am seeing if the weather was cooler. I will continue to monitor the disease and can now apply something if the disease decides to get nasty! I anticipate that if the temperatures drop slightly I might again have a problem. I can only hope that temperatures drop enough that this disease becomes inactive! Here's hoping for a deep freeze!

Greens in full sun are still synthetic pesticide free 5 months later!