Try mesotrione plus triclopyr. If it is creeping bentgrass, it will get smoked. If it’s not, I’m out of ideas (does look like creeping bent).

 

Try mesotrione plus triclopyr. If it is creeping bentgrass, it will get smoked. If it's not, I'm out of ideas (does look like creeping bent).

Any certain time of year to apply? How many treatments, one time will nuke it?

 

I did it In late Summer a couple years ago. Several bad patches. Full label rates of both the meso and triclopyr. Smoked it, one and done. If the meso and triclopyr don’t do the job, then it’s not bentgrass.

(Keep in mind the three week wait between the app and seeding for triclopyr if you plan to seed — for us here, three weeks from now would be on the getting late side of things for seeding fescue)

 

Thanks, will try it.

 

Mesotrione--Tenacity. And you are lucky--couple years ago--no chemical was available for invasive bent.

https://u.osu.edu/athleticfieldmanagement/2017/04/06/selective-creeping-bentgrass-control/

 

What did you guys do back then? Glyphosate and reseed?

 

Spot treatment of Meso and starter. Meso shuts down the bent for 3-4 weeks. The fertilizer supercharges the existing turf in the invasive spots. Been doing this for three years. Retreatment until gone.

 

Bentgrass is shallow rooted and my experience with it is it likes wet, poorly drained areas, at least in the climate here. I see it alot from over-irrigation too. If you don’t fix the why of why it was able to establish and outcompete the fescue, it will tend to come back. If that’s not how it got there to begin with then carry on .

Cultural practice for prevention would include ensuring reasonably good drainage, establishing an irrigation plan of no more than twice a week and irrigation amounts that allow keeping surface soil on the dry side between irrigation events (which also helps keep alot of other weeds in check too). Kill it, get your fescue thickened up where it was and implement cultural practices that help prevent it returning.

 

Getting the PH up over 6 helps also. I've renovated many lawns that were basically taken over by bentgrass. Once it has established itself for decades, there is always a chance it will return. That's why we keep meso and starter on the truck. It's a battle but it can be controlled. Keeping the lawn mowed at the highest level possible is a major help. If it establishes, there is a wall of defense until its treated.