Friday, 17 May 2013

Good God It Works

So it has been a while since my last post and it is not because nothing has been happening. It has been busy running a golf course with a 3 person crew including myself. Lately people have been asking me how my battle with disease has been going so I thought I would throw out an update to catch everyone up.

I have continued on with my updated plan that I revised in February  Plans are always subject to change and my disease management plan has continued to evolve this spring. So far the plan has been a great success with no major disease outbreaks to speak of. My applications of Civitas and phosphites every 3 weeks combined with my GP fertility program have really produced amazing results. As of today the greens are full of disease quite uniformly but the severity of that disease is minimal. By minimal I mean that you can see it, but barely, and it's not getting worse. Here is a picture to show just how bad it is.
If you look really hard you can see many disease infection centers but nothing serious. This is the worst I've seen it this year.
As you can see the Poa annua is in full bloom and this is probably one of the reasons I am seeing increased fusarium patch pressure lately. I have adjusted my management program to compensate for this by raising the HOC to .125" and rolling daily. We have also increased the VMC in the greens when irrigating to 25-35% range to keep the poa happy.

Last month we experienced record dry and high temperatures. We went almost 2 weeks without rain and temperatures rose into the low 30's. This combined with the poa going into seed head production worried me. During periods of dry hot weather I have decreased the ratio of ammonium sulphate in my fertilizer applications to further reduce any stress on the poa.

Last year I played around a lot with Civitas and phosphite rates and timings and I think that what I am doing now is the best yet. Currently I am applying Civitas and phosphites every 3 weeks to putting greens only. Civitas at 0.375ml per 100m2 and phosphites at .035kg Phosphite/100m2. The timing is based on the optimum for phosphites as outlined by research done by John Dempsey. I try and apply them on dry days if possible and do not water them in. I really don't like the colour of Civitas as it gives a fake/cheap green appearance to the greens that looks unnatural. Applying it every 3 weeks cuts down on the frequency of the gross green colour and I have found that a light iron application a few days after the Civitas application really helps the colours blend into the surrounds.

Gotta hate the colour of Civitas especially on white Poa
seed head. YUCK
Another thing that I have been playing around with is nitrogen source based on my perceived disease threat. My two nitrogen sources are ammonium sulphate and urea. I adjust the ratio of the two sources as I feel is needed. I apply a higher ratio of ammonium sulphate when disease pressure is higher (cool wet weather) and more urea when it's not. I also increase iron sulphate rates to help with the disease suppression as sulphur has been shown to suppress Microdochium nivale. No I'm not pouring on the sulphur as this has been shown to have a higher EIQ (Environmental Impact Quotent) than traditional pesticides but rather just slightly increase it's content in my weekly fertilizer applications to further help the cause.
My GP fertility planner makes it easy to adjust nitrogen ratios.
So far I haven't really measure any significant temperature differences between putting greens but this could be due to the tree work we have done over the years. So far all fertilizer applications have been consistent for all greens.

This year I did aeration differently than in previous years. I started it in late February and used water to wash the sand into the holes. The thinking behind this was that we had always experienced major disease outbreaks following aeration in April. In February the disease pressure was usually low. By washing in the sand I could minimize the mechanical stress on the plant. This approach worked great and allowed me to get by without having to apply any traditional pesticides. The holes took a little longer to heal over (2 weeks total) but this wasn't a big deal as there were virtually no golfers this time of year.

For my sunniest green (the 8th) I have used only Civitas and phosphites since June 6th, 2012 with absolutely no sign of any disease activity. For the most part this is due to dumb luck but I am now confident that I can do it again with what I have learned. For all my other greens it has been since last November. We had major frost damage to a few of our greens so they received a precautionary traditional pesticide application in February of this year just to ensure their recovery went smoothly. I am still a skeptic (even still) so I don't yet want to rule out the use of other traditional products for disease suppression. I have been learning as I go and every now and again something happens where a fall back to traditional medicine is required.

Speaking of slip ups. Remember the disease outbreak last November? All of the spots that were damaged have filled in with bentgrass that was overseeded last summer. Cool!
Old disease spots now filled with bentgrass.
An anecdotal observation is that as time goes on the greens that have been successful with only Civitas and Phosphites for disease suppression have been the best greens on the course. As time goes on they seem to only get better and better. I wonder if there is something more happening here?

Here's a comparison of my practices the past few years.

From January 1st to May 12, 2012, 7 traditional pesticide applications were required to control Microdochium nivale on my putting greens. This year for the same time period I have made 5 applications of Civitas and phosphites and 1 application of Iprodione to the 3 damaged greens mentioned earlier. The cost of Civitas so far this year totals up to $870 for 1 acre of putting greens and the phosphites add up to about $274. The one application I made of Iprodione to 3 greens cost $209.40! for a total of about $1,353.40 for 5 months of fusarium control on my putting greens. Last year the cost using traditional pesticides only was $2,734 and this was often only for a few greens and not everything. My program for disease control products costs about half of that in previous years, covers all of my greens, and so far has provided complete disease control and better playing conditions.

In 2012 the year to date fertilizer rates applied to greens was as follows:
0.69 Kg N/100m2
0 P
0.38 Kg K/100m2
0.73 Kg S/100m2

This year the totals look something like this using the growth potential formula to determine rates:

0.35 Kg N/100m2
0.27 Kg K/100m2
0.18 Kg S/100m2

As you can see the nitrogen rates are nearly half that of previous years and this is one of the main reasons I think there has been such a big difference. Sulphur rates are also 3x less this year which further reduces the environmental impact of my fertilizer applications. So far fertilizer applications have cost me about $200 per acre for the year. This doesn't include application costs for diesel and my time. I came under fire this spring for advertising I was going out with a $5 fertilizer application or something because that didn't include the cost application etc. For me the cost of applying fertilizer weekly at very low and precise rates is more than made up for by the increase in playing condition quality, reduced disease activity, and the reduced environmental impact of my pest control products used. The precise control also allows me to adjust to freak weather occurrences like the week of 30C+ weather in May! The growth potential went from about 33% to 98% very quickly. I was able to quickly adapt and probably warded off a dollar spot outbreak by increasing nitrogen inputs as required by the plant.  I keep saying this but I highly recommend checking out the growth potential formula developed by PACE Turf and how it can be used for calculating fertilizer requirements.
You can see the fusarium if you look really hard!
I have to say that using the growth potential formula for the first time in the spring was a challenge though. It took all I had not to throw out a high rate of nitrogen to green things up quickly, especially on the greens that suffered the frost damage. With a lot of patients and trust in my plan everything came along very nicely and even the damaged greens have recovered nicely.

Last year I was faced with pushing and pushing and waiting for thresholds to develop which was very stressful. I was often looking at disease pressure like the following picture which was hard day to day.

Where today at about the same time of year I am faced with this:
Last year I had no clue what I was doing. I was driving my pesticide use down by simply increasing my disease thresholds and nothing else really. Now I am doing much more.

I have found a way to make disease control products that are certified organic work without the use of traditional pesticides. I am actively adjusting my fertility program to compensate for changes in weather and disease pressure and in the process have reduced costs and the impact to the environment by using safer products on the course. Give it a try. It's not easy, but it's totally worth it!
I am going to take the almost daily occurance of
amphibians on the greens as a good sign.

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