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Tenacity on St Augustine ?

26K views 28 replies 9 participants last post by  kb02gt  
#1 ·
Anyone ever try this. I've read the label and it says it can be used on st Augustine when growing as did. I don't really see what the difference is however?

If that the case I'm guessing a 1/2 rate app on st Augustine should be okay ?
 
#6 ·
Then I think I'll go in at the recommended rate. I guess it really won't matter as it's like a 12 x 5 foot area of crabgrass. Then will go ahead and spray some of the surrounding area as well especially since it's in the backyard and the growing.

I did pickup some "Garden Weasel Crabgrass Killer" as well. Not sure if its a gimmick or not but hey it's worth a shot too. Starting to learn there is a lot of experimentation involved in lawn care.
 
#7 ·
kb02gt said:
Then I think I'll go in at the recommended rate. I guess it really won't matter as it's like a 12 x 5 foot area of crabgrass. Then will go ahead and spray some of the surrounding area as well especially since it's in the backyard and the growing.
Just realize it's not going to be a one-and-done thing with the Tenacity. I've seen CG recover from Tenacity if only one app is done. I have no idea though how well St. Aug. tolerates multiple apps, or if it tolerates the 4oz/A rate well, as I have no experience with that grass type other than looking at it and walking through it. Tolerance may also very by cultivar. But one good thing about Tenacity if you can swing 2 apps, is that it can help kill Crabgrass that is in the medium tiller stage. Also, you can try following up with a standard crabgrass herbicide once the Tenacity turns it white if you can't swing for a 2nd app of Tenacity. Good luck.
 
#10 ·
Green said:
kb02gt said:
Then I think I'll go in at the recommended rate. I guess it really won't matter as it's like a 12 x 5 foot area of crabgrass. Then will go ahead and spray some of the surrounding area as well especially since it's in the backyard and the growing.
Just realize it's not going to be a one-and-done thing with the Tenacity. I've seen CG recover from Tenacity if only one app is done. I have no idea though how well St. Aug. tolerates multiple apps, or if it tolerates the 4oz/A rate well, as I have no experience with that grass type other than looking at it and walking through it. Tolerance may also very by cultivar. But one good thing about Tenacity if you can swing 2 apps, is that it can help kill Crabgrass that is in the medium tiller stage. Also, you can try following up with a standard crabgrass herbicide once the Tenacity turns it white if you can't swing for a 2nd app of Tenacity. Good luck.
Hmmmm, thats good point. Well if the st. aug dies in that area then i'll just have to replug it, sigh. But will only go in with the 1 app, maybe 1/2 rate. Thing is, i'm not so sure how far these products travel down the st. aug stolons. I've just hit the CB with a heavy dose of atrazine 2 days ago, and then the weasel will be this weekend. Followed by Tenacity the following weekend. That should take care of it for sure. I should take some before and after pictures now that i think of it. I'll also monitor the Bermuda in that area to see how it is affected as well. Next year will get a few test beds going to try out different things/products.
 
#11 ·
@kb02gt, minimum rate won't do much against crabgrass. I'd use the full 4oz rate, and only spray where you have to.

Here's the thing. Even cool season grasses turn white temporarily when you do that. Some types more than others. Doesn't mean it's dying. It can recover. Even Crabgrass can, if not hit twice or with an additional mode of action like you are doing.

I love Tenacity. If I had St. Aug. I'd be trying it out on it for sure.

We use Tenacity here to hurt Zoysia where it's an undesired component of a lawn, among other things. My neighbor said it kept it from spreading last year. Zoysia is not labeled for it, of course, unlike St. Aug. We don't really have other warm season turf grasses up here...just Zoysia.
 
#13 ·
Greendoc said:
Tenacity + Atrazine or Simazine on St Augustine is an approved combination by Syngenta. It reduces bleaching and increases toxic effect on the weeds. Use the lowest label rate of Tenacity and half the label rate of Atrazine. This may be repeated in 14 days.
@Greendoc do you have any information to link about this Atrazine+tenacity combination. I would love to read up on this
 
#14 ·
Well am pausing on the Tenacity for now. The garden weasel I will still try since I have it. However I've picked up a bottle of Dismiss NXT which is supposed to kill everything (except Bermuda of course 🤔) , torpedo even after a few apps, and not harm the st Aug so will see. We have a lot of rain forcasted for this week so will have to wait till the next.
 
#15 ·
I have used tenacity at 4oz per acre on centipede and SA. It does turn the SA white. Did not seem to impact the centipede. Someone above made a comment about it hurting zoysia. What zoysia I hve in my yard did not seem affected by it. The SA did not all turn white, but what turned white a while back is still white, but also spreading.

Edit - early march was when it was applied
 
#17 ·
Midget said:
@kb02gt- I would NEVER go against Greendoc, but, I would rather try a "natural" product before a 3 chemical mix. Having used Garden Weasel and since you have it, please try it first! Again, be sure to wet the area - the white powder should turn yellow after applied...
I'm pretty sure this weekend I'm going to take a section, small one, and try this mixture.
I'm using tenacity and atrazine to what effect it has on Bermuda grass only.
 
#18 ·
Midget said:
@kb02gt- I would NEVER go against Greendoc, but, I would rather try a "natural" product before a 3 chemical mix. Having used Garden Weasel and since you have it, please try it first! Again, be sure to wet the area - the white powder should turn yellow after applied...
I agree as well and with the feedback i've seen on the "Garden Weasel" i will be giving it a shot. But it will have to wait till next time. The main reason for this is that while i was out there spraying i was in such a rush that i forgot to leave a chunk of crabgrass to test the garden weasel with. However i do have a combination of torpedo, crabgrass, nutsedge, and killinga over a large area. And also because it cost over $100 bucks for the little bottle, lol, then it might as well just be blanketed. As for the Dimiss NXT, was going to wait till the rain forcast was better but i could not wait and have taken my chances. Looks like it is rainy ready in 4 hours, so 2 more hours left. Hoping for no rain. Did a blanket spray at .32oz/gallon (blue dye included, sigh.....) which is a little heavy and covered just 3500 square feet. The smell to me was awful and probably should have worn a mask. As for the Bermuda, im going to see how the Floratam fairs against it as it seems to be emerging through the bermuda now that spring is almost here, but thats a battle that might have to wait till next year. At this point the garden weasel will be more of a spot spray. But yeah if GW could kill all of the above and be used to blanket the lawn, and be safe and healthy, then that would be my first choice for sure :thumbup:
 
#19 ·
CenlaLowell said:
Midget said:
@kb02gt- I would NEVER go against Greendoc, but, I would rather try a "natural" product before a 3 chemical mix. Having used Garden Weasel and since you have it, please try it first! Again, be sure to wet the area - the white powder should turn yellow after applied...
I'm pretty sure this weekend I'm going to take a section, small one, and try this mixture.
I'm using tenacity and atrazine to what effect it has on Bermuda grass only.
Have a really good feeling about that combo. I almost wonder if that is what was included in the "special sauce" no one knew about. https://www.lawnsite.com/threads/i-killed-bermuda-in-st-augustine.300032/page-10
May want to start from page 1 however. I've not read the whole way through it, but apparently there was once a formula mentioned on the UFAS site for killing Bermuda in St. Augustine. But it was eventually taken down.

A really good link that came from the discussion was this one: http://www.realgreenlawns.com/austin_tx_texas/burmudafromstaugustine.htm

This one i found out on the net as someone here claims asulox can work: https://turfgrass.com/get-bermuda-out-of-st-augustine/

Seems the necessary tools do exist, i guess its just a matter of finding the right combination which is no walk in the park.
 
#21 ·
Greendoc said:
That special sauce was a combination of Assulox, Atrazine, Basagran and Prograss(Ethofumesate).
:thumbup: :thumbup: :thumbup: :thumbup: :thumbup: :thumbup: :thumbup:

Thank you (times a million)

Just spoke with one of the lawn care guys this morning. Discussing products, etc. Really cool guy, and learned a little about spraying technique, etc. He mentioned the ratio of Atrazine to knock out Bermuda was 25oz/150gallons i had to use my memory to remember it. Does that sound about right to you? (this was for Atrazine by itself) Also mentioned that Assulox was banned which i had not realized :( . Hmmmm, never heard of Basagran . Will definitely be looking into this. Based on the results @CenlaLowell had with Prograss and Atrazine, i can only imagine that adding the other 2 would for sure annihilate the Bermuda.
 
#22 ·
kb02gt said:
Greendoc said:
That special sauce was a combination of Assulox, Atrazine, Basagran and Prograss(Ethofumesate).
:thumbup: :thumbup: :thumbup: :thumbup: :thumbup: :thumbup: :thumbup:

Thank you (times a million)

Just spoke with one of the lawn care guys this morning. Discussing products, etc. Really cool guy, and learned a little about spraying technique, etc. He mentioned the ratio of Atrazine to knock out Bermuda was 25oz/150gallons i had to use my memory to remember it. Does that sound about right to you? (this was for Atrazine by itself) Also mentioned that Assulox was banned which i had not realized :( . Hmmmm, never heard of Basagran . Will definitely be looking into this. Based on the results @CenlaLowell had with Prograss and Atrazine, i can only imagine that adding the other 2 would for sure annihilate the Bermuda.
I can tell from the experience I had you will need much more atrazine. That guy must have been spraying the atrazine that farmers use which has a A.I of 41%. Ours is not near that potent, so last time I sprayed I used 64 oz to 16 gallons of water.
 
#23 ·
Basagran was the second component of a Premix marketed by BASF. Called Prompt. It contained Atrazine and Basagran. Prompt was a convenient way to get turf labeled Atrazine in the 1990s. Assulox was allowed on residential turf until 2000. Manufacturer decided not to submit the data to keep it as a residential turf herbicide.
 
#24 ·
Greendoc said:
Basagran was the second component of a Premix marketed by BASF. Called Prompt. It contained Atrazine and Basagran. Prompt was a convenient way to get turf labeled Atrazine in the 1990s. Assulox was allowed on residential turf until 2000. Manufacturer decided not to submit the data to keep it as a residential turf herbicide.
Interesting..., i wonder why the would do something like that. It seems to me that a product also labeled for residential use would drive down costs for everyone while selling more product. The only 3 reason i could come up with is 1) the production of the product was the bottle neck or 2) possibly they wanted to keep any overhead costs to a miniumum, or 3) The key buyers of Assulox do not want to lose market share to the homeowner. Just looked and it seems domyown.com will sell it to Florida although there are many other states they will not sell it to.
 
#25 ·
CenlaLowell said:
kb02gt said:
Greendoc said:
That special sauce was a combination of Assulox, Atrazine, Basagran and Prograss(Ethofumesate).
:thumbup: :thumbup: :thumbup: :thumbup: :thumbup: :thumbup: :thumbup:

Thank you (times a million)

Just spoke with one of the lawn care guys this morning. Discussing products, etc. Really cool guy, and learned a little about spraying technique, etc. He mentioned the ratio of Atrazine to knock out Bermuda was 25oz/150gallons i had to use my memory to remember it. Does that sound about right to you? (this was for Atrazine by itself) Also mentioned that Assulox was banned which i had not realized :( . Hmmmm, never heard of Basagran . Will definitely be looking into this. Based on the results @CenlaLowell had with Prograss and Atrazine, i can only imagine that adding the other 2 would for sure annihilate the Bermuda.
I can tell from the experience I had you will need much more atrazine. That guy must have been spraying the atrazine that farmers use which has a A.I of 41%. Ours is not near that potent, so last time I sprayed I used 64 oz to 16 gallons of water.
:eek: Wow, that seems like a lot of Atrazine. Wishing i had thought to ask for the percentage.
 
#26 ·
kb02gt said:
CenlaLowell said:
kb02gt said:
:thumbup: :thumbup: :thumbup: :thumbup: :thumbup: :thumbup: :thumbup:

Thank you (times a million)

Just spoke with one of the lawn care guys this morning. Discussing products, etc. Really cool guy, and learned a little about spraying technique, etc. He mentioned the ratio of Atrazine to knock out Bermuda was 25oz/150gallons i had to use my memory to remember it. Does that sound about right to you? (this was for Atrazine by itself) Also mentioned that Assulox was banned which i had not realized :( . Hmmmm, never heard of Basagran . Will definitely be looking into this. Based on the results @CenlaLowell had with Prograss and Atrazine, i can only imagine that adding the other 2 would for sure annihilate the Bermuda.
I can tell from the experience I had you will need much more atrazine. That guy must have been spraying the atrazine that farmers use which has a A.I of 41%. Ours is not near that potent, so last time I sprayed I used 64 oz to 16 gallons of water.
:eek: Wow, that seems like a lot of Atrazine. Wishing i had thought to ask for the percentage.
Yeah it is a gallon doesn't cover very much. Atrazine for homeowners is at 4%.