Spot Spraying with Tenacity....What's next?

[Smolenski7]

So the long and short of it is I just spot sprayed a second application of Tenacity to what I think is both Poa-Anua and Triv around my yard. The first app. was 2 weeks ago and much (not all) of what I sprayed turned white. I just sprayed again at the same rate.
1. What should I expect after the 2nd application?
2. If I'm not happy with the results, when (or should?) I spay again?

[northeastlawn]

The first thing to realize is that tenacity kills slowly and everything that turns white does not necessarily die. You gotta think “control” vs some magic spray that just kills poa-a and triv. It defiantly doesn’t kill triv and even some mature stubborn poa-a varierties can survive it. It does suppress it though and if you have KBG, that’s enough to make the lawn better. It really becomes a slow gradual yearly process of less poa-a.

With that said the poa-a turns white, then starts to thin and brown out. It almost wilts or melt away.

If you have a lot of cold wet weather, poa-a can easily out grow the tenacity. If we have a dry warm spring, the poa-a takes more of a beating and you will get a better kill ratio. But some will come back.

[Smolenski7]

So, how much is too much? I've sprayed twice, separated by 2 weeks. Some spots have definitely turned white, while others are white......just not as much. Should I spot spray again? If so, how long should I wait?

[northeastlawn]

You will kind of notice a pattern….

4oz/ac rate 10-14 days a part
2oz/ac rate 7 days a part
1oz/ac 3-4 days a part

In the spring the studies I see mentioned say that more frequent intervals of tenacity in the spring give you a better chance at control.

But a lot depends on the weather, cloudy and rainy, and the poa-a gets through the tenacity just fine

Dry and warm and the poa-a browns and dies in a few spot sprays. We had a week of mid 70’s and no rain, the poa-a suddenly all bleached and browned.

The weather conditions and your annual tenacity limit will limit how long you can keep spraying.

It’s become a yearly thing for me, I never totally control the poa-a, just slow it down and hopefully kill some of it.

After Memorial Day I may try xonerate on mature poa-a, but it’s expensive and the kbg seed heads I have now make distinguishing the poa a lot harder.

[Irisbergamot]

This season I hit it with 4oz rate every 3 days.
Of course this was wrong.

The study said to hit it with 2oz rate every 3 days.

Thank God my fescue/kbg are ok. The poa looks like lightning.