# Diquat vs Glyphosate



## Jeremy3292 (Apr 30, 2020)

I apologize if this has been discussed previously, but I couldn't find any good info on it. It seems everyone in the forum is glyphosate over diquat dibromide. Any reasons why? Are they same mode of action? Can't you use both in dormant bermuda to kill off winter weeds?


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## CarolinaCuttin (Sep 6, 2019)

Reward (diquat) can't be counted on to kill a mature and healthy plant. It will burn down the top growth, but it won't kill to the roots. RoundUp QuickPro is glyphosate + diquat and that's a good mix for sure.


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## Jeremy3292 (Apr 30, 2020)

CarolinaCuttin said:


> Reward (diquat) can't be counted on to kill a mature and healthy plant. It will burn down the top growth, but it won't kill to the roots. RoundUp QuickPro is glyphosate + diquat and that's a good mix for sure.


So then wouldn't diquat be good for suppressing winter weeds in dormant bermuda with less risk to damaging the bermuda vs glyphosate?


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## CarolinaCuttin (Sep 6, 2019)

Jeremy3292 said:


> CarolinaCuttin said:
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As long as your turf is dormant there is no threat from glyphosate. It is absorbed by the leaf tissue, same as diquat. Even if bermuda isn't dormant, neither glyphosate nor diquat will kill your healthy bermuda. Many members have tried and even multiple rounds of glyphosate doesn't get it done.


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## Jeremy3292 (Apr 30, 2020)

CarolinaCuttin said:


> Jeremy3292 said:
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> > CarolinaCuttin said:
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Perfect, thanks. What temps can you use glyphosate at in dormant bermuda? Once you get into the 50s bermuda may not be fully dormant, but you don't want to be spraying weeds in the 20s right?


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## CarolinaCuttin (Sep 6, 2019)

@Jeremy3292 I like to do it when I've recently had a frost but I try to choose a day with full sun in the high 40s or low 50s because extremely cold temperatures are likely to impede absorption of the herbicide. Once bermuda goes fully dormant, it isn't constantly popping in and out of dormancy over the winter as you get warm. It's takes a good run of really warm days to get it to start to really pop out, so as long as you haven't had an extended warm spell you'll be fine.


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## Jeremy3292 (Apr 30, 2020)

CarolinaCuttin said:


> @Jeremy3292 I like to do it when I've recently had a frost but I try to choose a day with full sun in the high 40s or low 50s because extremely cold temperatures are likely to impede absorption of the herbicide. Once bermuda goes fully dormant, it isn't constantly popping in and out of dormancy over the winter as you get warm. It's takes a good run of really warm days to get it to start to really pop out, so as long as you haven't had an extended warm spell you'll be fine.


Thanks! Was just trying to figure out the difference between the two - Spectracide only sells diquat which I thought was interesting.


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## CarolinaCuttin (Sep 6, 2019)

@Jeremy3292 There are some supers down south that use diquat before overseeding with ryegrass. It burns down the top growth of the bermuda to allow the seed to get into the canopy and inhibits competition from the bermuda for a period of time after seeding. Diquat will ding things up but I wouldn't count on it to kill a plant with one application.


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## Mister Bill (Apr 12, 2019)

Jeremy3292 said:


> CarolinaCuttin said:
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> 
> > Reward (diquat) can't be counted on to kill a mature and healthy plant. It will burn down the top growth, but it won't kill to the roots. RoundUp QuickPro is glyphosate + diquat and that's a good mix for sure.
> ...


I do not know the difference between what you ask, but I can say with experience that Bermuda never really goes fully dormant in the transition areas where we live. For this reason I quit using any glyphosate type herbicides in the winter, as the application always stunted the Bermuda and slowed green up in the spring taking a while to fill back in. The Bermuda may appear to be dormant, but it usually isn't fully dormant at the crown. I've gone to using ester based 3-ways in the winter as an alternative with much better results. YMMV.


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## Gilley11 (Nov 3, 2019)

I'm not a fan of the Roundup QuickPro mix. The diquat seems to be added just for a visual for the consumer....they see quick results and think it's a good product.

A neighbor of mine bought it and I sprayed it for them. What I saw were results that weren't as good as glypho by itself. I think the diquat killed parts of the plant that didn't have time to fully absorb the glypho and the glypho couldn't fully do its thing.

It seems like RoundUp wanted something out there that there wasn't a generic of so they did this combo. I'd stick with the off brand 41% glypho products and save your money.


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## Mister Bill (Apr 12, 2019)

Gilley11 said:


> I'm not a fan of the Roundup QuickPro mix. The diquat seems to be added just for a visual for the consumer....they see quick results and think it's a good product.
> 
> A neighbor of mine bought it and I sprayed it for them. What I saw were results that weren't as good as glypho by itself. I think the diquat killed parts of the plant that didn't have time to fully absorb the glypho and the glypho couldn't fully do its thing.
> 
> It seems like RoundUp wanted something out there that there wasn't a generic of so they did this combo. I'd stick with the off brand 41% glypho products and save your money.


You bring up an excellent point. I see people using a kicker in a three way to give a fast burn down, but as you point out, this doesn't allow the plant to absorb the three way herbicide mix as well as it could. Instant gratification is rarely the best solution. Excellent analysis.


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## ktgrok (May 25, 2019)

Jeremy3292 said:


> CarolinaCuttin said:
> 
> 
> > @Jeremy3292 I like to do it when I've recently had a frost but I try to choose a day with full sun in the high 40s or low 50s because extremely cold temperatures are likely to impede absorption of the herbicide. Once bermuda goes fully dormant, it isn't constantly popping in and out of dormancy over the winter as you get warm. It's takes a good run of really warm days to get it to start to really pop out, so as long as you haven't had an extended warm spell you'll be fine.
> ...


Well, Spectracide is my least favorite brand of anything lawn related, so..there is that, lol.


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## CarolinaCuttin (Sep 6, 2019)

Bermuda definitely goes fully dormant in the Carolinas. RoundUp gets sprayed on dormant golf courses all the time. That doesn't mean it has to be done that way, but you can absolutely apply it to dormant turf safely.


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## Mister Bill (Apr 12, 2019)

CarolinaCuttin said:


> Bermuda definitely goes fully dormant in the Carolinas. RoundUp gets sprayed on dormant golf courses all the time. That doesn't mean it has to be done that way, but you can absolutely apply it to dormant turf safely.


Year in and year out? I disagree with Bermuda going fully dormant in transition areas, but do agree glyphosate will not hurt fully dormant Bermuda. As said, YMMV. Proceed with caution.


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## Jeremy3292 (Apr 30, 2020)

Does it matter which Roundup glyphosate you choose? There is 2%, 18%, 41%, and higher that I've seen. I believe the lower percentages are already premixed, however.


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## CarolinaCuttin (Sep 6, 2019)

Jeremy3292 said:


> Does it matter which Roundup glyphosate you choose? There is 2%, 18%, 41%, and higher that I've seen. I believe the lower percentages are already premixed, however.


2% is ready to spray and 41% is the standard concentrate. It doesn't matter what you buy, you should let your wallet be your guide here.


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