Acidiovorax catalina...aka Bacterial Wilt...

We have been dealing with an extremely rare case of bacterial wilt on our greens. I remember when we first started seeing symptoms of the problem. It was around the time we thought our applications of primo were wearing off and the plant was exhibiting vigorous growth as the chemical degraded. Primo is a plant growth regulator that slows vertical plant growth. We have had professors from Michigan State, Clemson, and NC State (possibly other schools as well) visit. We have had visits from Paul Latshaw Sr. (he is a very prominent superintendent). We have sent samples to Rutgers, Michigan State, and Colorado State; all coming back confirming that it is a bacterial wilt problem. The only downside is no one has any proven recommendations as to what we can do to solve the problem.

You can see the turf elongating in this photo, this was the very early stages of the problem

So basically we have been mowing the greens every other night to reduce mowing stress. We have raised the height of cut from .110" during the tournament with green speeds near 12.5', to .125" after the tournament with green speeds near 10.5' to .145" with green speeds near 9.0' and now we have just raised the height from .150" to .155" with green speeds near 7.0'. Along with our mowing at night and frequent syringing, we have been spraying the greens with different experimental chemicals. We have different test plots on nearly every green. We have done so many sprays with different products, I do not even know what has worked and what has not.
Here is one of the test plots on the chipping green

What the bacteria does: The bacteria lives inside the plant. It is thought to enter the plant when the blade is cut with a mower. When inspected under a microscope, the bacteria streams out of the xylem with like a "fire hose". The bacteria causes the plant to elongate. We would then mow the elongated plant causing the plant to be scalped. The scalped turf would be put under increased stress causing root reserves to be spent to aid turf recovery. Currently we have very short roots. There are areas on the edges of the greens where the mower has caused severe scalping. In these areas turf has been lost and the areas are filling in with algae and the bermuda grass is intruding. I have read on the internet, the problem will persist until day temperatures return to mid 70's.

"Rod Shaped" bacteria fill the veins in the plant

"Rod Shaped" bacteria exiting the plant

The plant is etiolated- thinning and elongating
You can see how the turf is elongated in this photo

Bermuda intrusion on the edge of the green

You can see how the turf is deteriorating here in the clean-up pass on the green

The best solution to the problem would be to rebuild the greens. The soil needs to be replaced, becasue we think it is a soil-bourne problem-simply re-sodding the areas would not help. I think we will try to continue to overseed the greens to get more bentgrass to grow. I would like to see the greens next spring to see what they do to get them in shape for the tournament.

We tried to plug the bad areas out of the green, but the bacteria infected the plugs and killed them rather quickly