Wednesday, 22 January 2014

Rolling and Fusarium OSU Trial Update

A few years ago the turf industry in BC was facing a pesticide ban and our association set out to fight the ban successfully. At the time I was worried that we needed to also spend some resources in coming up with alternative pest control measures just in case the ban was enacted. I also wrote to the Western Canada Turfgrass Association with my concerns. Ever since then, alternative pest control strategies have been the focus of this blog.

Last fall I was contacted to by the WCTA to see what I thought would be some things to try. They were already interested in phosphite and Civitas but I also suggested lightweight rolling as I had seen some interesting things on my study green with regards to fusarium.

Just last month I was delighted to read that they had gone ahead with research funding at Oregon State University and had some preliminary results to share! I was also honored to be mentioned in one of the articles.

I won't repeat everything already in the above article so read it for yourself. Basically what they have found is that rolling does in fact seem to have some beneficial effects when it comes to fusarium patch control. They are also testing rolling frequency which is something that I think is important. From my findings 2 years ago it was quite apparent that further benefit was seen from more frequent rolling. This was something that might have been missed in past studies on rolling and fusarium because who would think that more rolling would be any different. Guess what, it is!
My findings from May 2012
It is really cool to see this kind of research being done and I am very proud that my association is funding research of this kind. I think that all members of the WTCA should be proud that not only are they fighting the ban, they are being proactive in funding research that will help us all be better turf managers.

Thursday, 16 January 2014

Fusarium Spread and Spot Treating Questions

Last year I wrote a post about how my approaches has much more disease than the rest of my pesticide free areas of the course. I hypothesized that it could be due to the overlap of fertilizer applications.

This year I was very careful to keep the fertility on my approaches lean and avoid overlap and this is what I got.
I've seen worse
Compared to a typical fairway

There is an obvious difference in the amount of disease even though they are the same species mix of grass, same height of cut and receive the same fertilizer treatments. Tees, Fairways and Approaches are all completely pesticide free.

At the time of writing that post a fellow Superintendent, Jason Hooper, suggested that it could be due to all the traffic the approaches got. At the time I didn't really think traffic had anything to do with it. The problem was is that I was thinking about traffic all wrong. I thought that the traffic would cause the disease by stressing the turf and making it more susceptible which was not an issue in my experience. What I failed to realize is that fusarium is spread by traffic! This is a big difference.

The approaches are run over by fairway mowers, approach mowers, and greens mowers! All of these mowers drag the mycelium around and spread the infection. They get three times the mower traffic than anywhere else on the course and the disease is at least 3 times as bad! Duh

I have some questions.

  • What impact on disease would spot treating individual infection points have on overall disease rates? Would there be a decrease in overall fusarium levels if spot applied early. How would the costs and EIQ differ between spot applications and broadcast sprays?
  • Does the incidence of disease we are seeing have to do more with conditions or the amount of mower traffic? Does more mowing = more disease?
  • Is there a difference in disease spread with mowers vs rollers. The idea being that mowers open the plant up and deposit the fusarium on fresh wounds, Rollers do not. This could be why we see a reduction in fusarium on plots that are rolled daily and cut every other day. Here are my observations and those of OSU on rolling and fusarium. Maybe rolling has no effect on fusarium and it's the lack of cutting that is the difference? I do not see any disease spread from my approaches onto my greens which suggests that the disease is only spread on mowers and not on wheels or rollers. This might also be why I have seen little disease on my greens so far this winter as I have been using Primo Maxx through the winter. I have only cut the greens once in the past 57 days! Maybe this is the sole reason I have seen success with fusarium in the past!?!?
  • Does rolling before mowing make an impact? Does the roller crush the fluffy white mycelium reducing disease spread from mowers?
  • Why are some turf species more susceptible to fusarium than others? Does the shape and mechanics of the leaf blade and how it's cut have anything to do with it?
  • Is it the height of cut or the frequency of cut that impacts disease more?
Oh so many questions.

What I plan on doing going forward is to treat individual fusarium patches on the greens. I will treat spots with a contact fungicide on days that I roll so that hopefully there is little active disease on the greens when I mow.

Now I'm thinking of a sprayer that detects disease spots and and selectively sprays them with the boom. Case in point: I sprayed all active spots on greens today with 3ml of daconil. The total area was 1.5 square meters or .04% of the putting green surface. This is slightly below label rate. This cost $0.08. A broadcast spray would have cost $259. Time will tell if spot treating fusarium on greens is a viable strategy. If I go out every day how long will I be able to keep up before I am overwhelmed?

Of course infection will pop up everywhere. I just think that it is made much worse by mowers...Who knows? Do you? Let me know what you think.

Spot Treatment using a spray bottle. 1.5m2 treated at a
cost of $0.08

Wednesday, 8 January 2014

Sustainable Fertilizer Use

One of the most over-used words in the turf industry the past few years has been "sustainable." People throw it around (and I'm just as guilty) but don't really have much data to back it up. What is sustainable? On the golf course it means using the minimum required resources to produce the expected conditions. This fall I decided to take part in the Global Soil Survey (GSS) to really get a good idea of how sustainable my fertilizer practices really were.

I sent off my samples and received my comprehensive soil test results typical of PACE Turf. Here are my test results.

And here is where the test results differ from your typical soils tests:

As can be seen from the above tables, I don't currently have any nutrient deficiencies according to the Minimum Level for Sustainable Nutrition guidelines (MLSN). I would also have to agree as my greens look pretty good. In Table 2 you basically get a report card of how you are doing. Table 3 tells you how much nutrients you have in the reserves and Table 4 tells what you need to add in case you have any nutrient deficiencies. Pretty Cool!

Now any smart person could probably figure this out. It's a few not too complicated calculations. The really cool thing about the GSS is that the data you submit (soil samples from good performing turf) goes into the database that helps refine the MLSN guidelines! As turf managers get more sustainable in the fertilizer practices we should get an even better idea of what truly sustainable fertilizer practices look like!

These results make it quite clear that I still have some work to do to become more sustainable in my fertilizer practices. Apparently I have been over-applying most elements over the years so for the next year this is what I am required to add as fertilizer.

Yep, that's right. Next year I am required to add almost nothing other than nitrogen to my putting greens! With the GSS we are instantly able to become as sustainable as possible. They give you fertilizer requirements for a wide range of nitrogen rates so you can match it for any circumstance and climate. If I apply nothing but nitrogen next season I will only be applying what the plant needs. This is only made possible, however, from years of over fertilizing and eventually I have to expect that a more complete fertilizer program will have to resume. But for the next season at least, I can ride the coat tails of "half assed and guessy" fertilizer practices of years past.

Disclaimer WARNING! Charts ahead, leave now if you find info-graphics offensive.

Now you might be wondering, how does this actually impact my operation? Here are a few charts.

The following chart shows how the total amount of fertilizer applied to my course has gone down. The biggest improvements have come from using simple source fertilizers instead of blended fertilizer. In 2012 I switched to UMAXX granular on fairways and was able to get rates much lower. In 2013 I got a new sprayer and was then able to apply straight urea to the fairways further driving down amounts of fertilizer required. This not only has an impact on fertilizer cost and environmental impact, but also on shipping costs and the resultant carbon emissions from that process.

The changes to my fertilizer programs have also made a big impact on my fertilizer budget. Some savings came from simply applying less but the biggest savings came from switching over to simple soluble source nutrients. If I am able to get away with the GSS suggested fertility program next year the cost of the soil tests will be higher than the cost of fertilizer for my putting greens! In future years I will expect this to rise as the nutrient reserves in the soil are depleted and I am forced to apply a more complete fertilizer program.

I have also taken into account the total time I spend applying fertilizer. Overall I have managed to keep the amount of time constant even though I am not making much more fertilizer applications. I have managed to do this with experience, and modern sprayer technology. 2012 was a year of big changes and experimentation for me. I also had a small pull behind sprayer that made every application a time consuming and laborious process.

Going forward I can now say with confidence that my fertilizer practices are as sustainable as I can possibly get them. I am not applying any fertilizer that isn't required and the conditions on the course have only improved. I really hope that more people will consider the GSS for their soil testing needs as it really helps add to the database and helps refine and redefine what sustainable fertilizer practices really are.

If anyone else has taken part in the GSS or has similar results to share please feel free to leave a comment below or join the discussion with me on twitter @Pendersuper