# Crabgrass tenacity experiment



## g-man

I saw a crabgrass growing in-between property lines. I would normally hand pull it, but I wanted to experiment.

When I threw seeds for the renovation, I was spraying tenacity too. I sprayed this area with just 4oz/acre rate of tenacity with 1g/ksqft carrier. This was a soil application ( no nis).

Day 8



I will resist the impulse to hand pull it and see how it looks next week.


----------



## g-man

@Virginiagal I don't think I've seen mature crabgrass treated with tenacity. I'm trying it out as an experiment. I would guess an application with nis might be more effective. So far it turned it a little white, but it is not dead.


----------



## Virginiagal

Just saw this while browsing. But you named me. Was I supposed to be notified that you were talking to me? Do I need to do something in settings? How do you do that thing, the @ symbol with someone's name in red?

Anyway, someone else had mentioned using Tenacity to treat crabgrass before seeding and I hadn't heard of that. Glad you're experimenting. The good thing would be that there's no seeding delay after using it. However, the dead plant, if it it's big, is still going to interfere with seed/soil contact. It's so spread out low to the ground. Maybe the thing to do would be to spray it to kill it and then hack it out. Maybe just hacking it off without spraying would be enough to set it back enough to not interfere with seeding? it will die anyway soon enough.


----------



## g-man

@Virginiagal in the board preference ensure the notifications for mention are on. 


To mentions someone, start @ and the name. A blue box will show up with names, click the right name. It will insert [ mention] ...


----------



## g-man

Day 14 post tenacity application ( no nis)



I don't think it is dead. It is not growing (lack of chlorophyll). I think someone that has a lot of crabgrass could use tenacity with nis 4 weeks prior to seed and then use it again at seed down.

I'm getting anxious to pull this thing. Let's see if j can wait one more week.


----------



## Virginiagal

@g-man Thanks for the explanations. I fixed my settings and am trying out the notification here, which seems to be working as you described.


----------



## Green

g-man said:


> @Virginiagal I don't think I've seen mature crabgrass treated with tenacity. I'm trying it out as an experiment. I would guess an application with nis might be more effective. So far it turned it a little white, but it is not dead.


I sprayed a fairly large crabgrass plant with NIS today with a hand spray bottle (fine mist). I'll report back when it dies. If I forget, let me know. And we can see how many days it takes.


----------



## pennstater2005

I think the label says up to 4 tillers, correct? Anyway, I've had limited success with Tenacity on crabgrass and I believe most of the stuff I try to use it on is too mature.


----------



## g-man

@Green what rate and carrier?


----------



## Green

g-man said:


> @Green what rate and carrier?


Standard rate, 4-6oz/A. Mixed at least a year ago (Tenacity keeps a long time I've found, even mixed) using my standard dilution, which is 1-1.5 gallons of water per thousand square feet, along with eyeballing 0.5-1oz NIS. I then put that into a spray bottle, which has been sitting since then. I did not mix it up prior to use yesterday, though I probably should have now that I think about it. I set the nozzle on the spray bottle to "spray" and misted the plant enough so I could see it was wet in most places, but not dripping. Sprayed around 5PM. It then air dried. It rained approx. 6 hours later. Dew point was 70.

How's that for detail?


----------



## g-man

24 days since application. 27aug2019

Last update. It survived. A single 4oz/acre rate via soil did not kill it and it seems at day 24 that it is starting to green up again.


----------



## Stuofsci02

I think a 2nd application 2 weeks ago would have taken it down. I believe on the bottle it mentions larger plants may take several apps


----------



## JDgreen18

Not exactly the same but I did a mix of tenacity and speedzone to hit a broad range of weeds with no surfactant because speedzone calls for none. It's been a week and I'm getting a pretty good hit on the crabgrass I sprayed.


----------



## g-man

I was trying to see what would happen if someone just used tenacity and seed at the same time. But the crabgrass survived, so that approach won't work.


----------



## JDgreen18

g-man said:


> I was trying to see what would happen if someone just used tenacity and seed at the same time. But the crabgrass survived, so that approach won't work.


What if you used a surfactant at seed down I wonder if the reduced rate would still get the kill. Or if the 4 oz per acre too low.


----------



## Green

Ok, I'm definitely going to hit mine with a 2nd app based on this...


----------

