June seems to be becoming a wet month in my part of the world. Last year it was consistently wet all month long. This year it started off with a few intense rain events then got decently nice for a week or so followed by an insane week of rain (same weather event that flooded Calgary). The first week of June my original disease management approach fell apart and I was forced to go back to traditional pesticides to regain control of the fusarium. I had to put all my plans on hold (including growth potential fertility) to regain control of the situation and push recovery on the greens. As the weather dried out the recovery was quick. Just as things were getting back into decent shape we got the same rain event that flooded parts of Alberta and that's where it got really bad. The fusarium exploded as the control provided from the Iprodione applied in early June faded. I was unable to apply any corrective fungicides until 3 days after the outbreak as it was raining much to hard. Things got even worse when the weather suddenly got very hot for the July 1 long weekend. The saturated greens were inundated with golfer traffic and they were almost turned into mud. It was very disheartening to say the least. With some stroke of luck I was able to keep everything alive and the greens are now in pretty good shape.
Looking back and after analysing my actions for that month I have made a few observations and changes to my fusarium management plan:
|Heavy golfer traffic on over-saturated greens = bad|
The growth rates in June were out of control. I am still using Primo Maxx to regulate growth but for some reason it just wasn't performing at all. I would get great growth rate control for about 3 days followed by intense growth action! It was so bad that we had to cut 2 times a day and were still scalping. It was this injury that probably made the disease attack worse. What I think went wrong here was that the Primo I was using was no longer working as I had been nursing the same jug since 2007! I had also increased nitrogen rates to push recovery which probably only made things worse. I should probably take my own advise more seriously in the future. Needless to say I bought a new jug of Primo and the growth rates have been much more consistent since then.
|The growth surges are exactly in tune with disease pressure. High growth = high disease activity|
As I had so much success with my Civitas and phosphite program through the winter I had decided to keep on with it through the summer which I now see as a mistake. I was applying these products on a 3 week cycle which worked great until about mid-May. At about this time I would notice an increased disease pressure mounting on the greens starting about 2 weeks after the application. Looking back I should have taken this as a sign. Man, I am dumb sometimes! Obviously as the temperatures warm up the plant's metabolism also increases and these products are used up quicker. Since the last big outbreak I have switched back to weekly applications of both of these products along with my fertilizer applications. In the future I plan on switching to weekly applications in April when I resume my weekly fertilizer applications. I will keep the overall monthly rates the same for now with just different application intervals. If this doesn't work I might try adapting my rates to the growth potential. Light and frequent, light and frequent, light and frequent, say it with me people.
What really clued me on was an application error on the 17th of June where I forgot to put my phosphite product in my spray tank while fertilizing greens. I remembered after I had already sprayed 2 greens but thought "what's the worst that could happen?" Well I was completely shocked to see the difference this product really made to my fusarium management program. I knew it worked, just not this much!
|Missed phosphite application on the left. Phosphites applied on the right.|
|The worst of it, I almost had a heart attack|
|Fluffy white death|
|Are you serious? Don't even start....|
It is months like this that I wish I had more bent in my greens. The bentgrass I had was completely untouched by the fusarium but when you have 95%+ poa and shit hits the fan you just need to grow poa! Fertilizer, water, and pesticides!
All in all I am pretty happy with the outcome of June. I was kicked in the ass but was able to come out of it in decent shape. I leaned a few lessons and should be better prepared come next year. I will also carry these lessons on into September as I once again try to fend off the fusarium as the season winds down. So far I have not been successful in making it through September without traditional pesticides so I hope the things I have learned over the past year will help me accomplish this goal. Fingers crossed!