[tnlynch81]

Sprayed these grassy weeds 3 weeks ago with the medium rate of celsius+some monument(for sedges) and MSO. The weather has finally warmed up to the 80's and 90's. Should I come back and spray at the low rate for round 2 or do you think these guys are on their way out.

 

[Movingshrub]

The info I saw from NC state concerning Celsius was the item will turn red/purple in 7 days and then necrosis followed by death at 14-28 days. If not controlled in 21-28 days, spray again.

I'd say spray again or you can wait until the 28 day mark.

 

[Ecks from Tex]

Sprayed these grassy weeds 3 weeks ago with the medium rate of celsius+some monument(for sedges) and MSO. The weather has finally warmed up to the 80's and 90's. Should I come back and spray at the low rate for round 2 or do you think these guys are on their way out.

Do not touch it if temps are above 90 for more than 3 days in a week. Celsius is rated to 90 unlike other herbicides, but you seriously test your luck if you spray with consistent temps above 90

That being said, you could easily spot spray that and it would probably have minimal loss since it's mostly crabgrass

 

[SCGrassMan]

Touch a foam sponge brush with some glyphosphate to it in the center. Show it who's boss.

 

[Spammage]

@tnlynch81 hit it again, but without the MSO. Use a non-ionic surfactant instead when temps get high.

 

[Rockinar]

I would just lift the leaves up above the grass. Then get some of that "deodorant stick" version of roundup and wipe it on the leaves with your finger tips (with a glove on of course).

 

[dfw_pilot]

Celsius is rated to 90 unlike other herbicides. . . .

Do you have a source for this? Other herbicides are usually limited to 85F. I've sprayed Bermuda with Celsius in 100F degrees without issue. The only warning on the label is for adjuvant or St. Augustine (which has been added in the more recent label updates).

 

[Ecks from Tex]

Celsius is rated to 90 unlike other herbicides. . . .

Do you have a source for this? Other herbicides are usually limited to 85F. I've sprayed Bermuda with Celsius in 100F degrees without issue. The only warning on the label is for adjuvant or St. Augustine (which has been added in the more recent label updates).

It's actually on the page of the label right before your reference (titled "precautions"). The precaution applies only to St Augustine. Bermuda is a stronger grass and can take a herbicide app in higher heat than SA of course, although the safe bet is to not exceed the max for other warm season grasses in my opinion.

 

[dfw_pilot]

I hear where you're coming from, but I disagree because I don't want to read too much into the restrictions for a Bermuda lawn. I think the St. Aug warning is new, too. YMMV.

 

[Spammage]

I've sprayed Bermuda with Celsius in 100F degrees without issue.

+1

 

[Ecks from Tex]

The SA warning was something I saw Allyn Hayne mention in one of his videos a year or two ago.

In general there is a risk applying any post-emergent herbicide when temps are above 90. The risk may be less with Bermuda, but it is still a risk. I completely toasted my lawn two years ago with Blindside (the recommended herbicide (ie, MSM) for warmer apps to SA if absolutely necessary).

 

[SCGrassMan]

I would just lift the leaves up above the grass. Then get some of that "deodorant stick" version of roundup and wipe it on the leaves with your finger tips (with a glove on of course).

That looks fancy... but a tad more expensive than a sponge brush

LOL @ "Deodorant stick".

 

[Topcat]

The SA warning was something I saw Allyn Hayne mention in one of his videos a year or two ago.

In general there is a risk applying any post-emergent herbicide when temps are above 90. The risk may be less with Bermuda, but it is still a risk. I completely toasted my lawn two years ago with Blindside (the recommended herbicide (ie, MSM) for warmer apps to SA if absolutely necessary).

Blindside Will torch your grass above 80-90 degrees. Been there done that. Celsius has proven to work for me in the dead of South Carolina summer with temps well over 90 with no harm to my lawn at all.

 

[w0lfe]

It's been touching near 90 for multiple days here, and I just sprayed my neighbors lawn and everything is dying but the Bermuda.

 

[tnlynch81]

I am going to give it one more week. Fertilized with AMS and Milo yesterday at just under 1lbN/K. Hopefully the growth will choke them out and finish the job. Temps next week are supposed to be low to mid 80's. If another round of Celsius doesn't take what's left of them out I will paint with glyphosate.

 

[dfw_pilot]

If another round of Celsius doesn't take what's left of them out I will paint with glyphosate.

:thumbup: That's what I recommend here for stubborn weeds. And remember, the hotter it is, the better Celsius works. Torch those suckers!

 

[Greendoc]

Celsius is not worth applying in cool weather. Neither are most of the SU herbicides. They work by inhibiting growth of fast growing weeds. Weeds slow down growth wise in response to cold temperatures and lack of sun just like how the turf does.