I maintain poa on the Eastern Shore of Maryland, and it's a very common occurrence for us. After my third year many things said below have helped me improve things dramatically. They are:
Michael Wagner said: I know this is a little late but the best anthracnose control I've seen is "Signature".
Agreed here. Briskway is also a nice tool to use, but hella expensive. I would add to keep 5 # / A of chlorothalonil in every tank you spray.
Jason Knuutila said: Frequent light top dress,no need to drag it in. It thickens the sheath protecting the crown, I almost think I could eliminate fungicides.
Daniel Shay said: I have found that DR Bruce Clark out of Rutgers has some of the best info on Anthracnose preventative and curative and has really helped me control Anthracnose.
Dr. Clarke is the man. Learn from him.
Michael Wagner said: I have noticed that when my mowers are sharp and adjusted properly anthracnose is far less severe than when the grass is being chewed off.
This x 100.
I would add:
Get a fan if you don't have one. A fan will turn your worst green into one of the best. If you don't have one set a buffalo turbine out and let that thing blow all day when it gets over 85. A fan is the great equalizer if your greens are shaded and have 0 air movement.
Check soil moisture and hand water exclusively if possible. Don't ever let them wilt hard, especially in the summer. This is one thing that kills me and really seems to set off anthracnose and melting out on my poa. We make sure they have a touch more than we think they need for the day. Doing this has kept my low areas clean as well.
Use a smooth roller on your mowers if possible. Use a walk mower. We also mow every day and stop rolling. Basically I want the canopy as tight and dry as possible. Normally we triplex, but I back off on 4 or 5 greens end of June and go to a walk mower. It's a hassle but it's helped a ton.
Venting is good, but be careful about overdoing it. Every 3 weeks is good for us.
I would make sure you aren't nuking your poa with N. We have so much nitrate release in the summer that I almost have to take it out of the tank. If your poa is getting too much N, back off so it's not out of control. On the flip side a lack of N would contribute to the Anthrac as well. It's a tough balancing act. I keep primo in the tank too.
For reference I've used the following fungicide rotation past 2 years: DMI's in spring every other spray (propi, tebu, triticonazoles) Disarm, Affirm, Iprodione/Tmeth alternates. Dac Action in the late spring. Summer is Signature/Tmeth/Iprodione (sans fertilizers) 3 times, briskway, tartan, insignia all with light chlorothalonil with every spray.
Good luck. Cultural > chemical is the way to go.