Virginia buttonweed (diodia v) in St Augustine

fritomd – posted 17 May 2007 18:01

Problem: Dallas Tx St Augustine is being overrun by virginia buttonweed. Any suggestions for eradication? Atrazine does NOT work.

can confront be used on St A despite warnings? How about Spotlight.

Where to buy the tough to find specialty herbicides over the internet?

thanks

murquiza – posted 17 May 2007 20:26

What I did in an area that I have that weed (or very similar) was apply Round-Up with a soaked cotton (use latex gloves!!!!). Fertilize and mow high.

In very little time St. Augustine was taking over the space used by the weeds.

TexanOne – posted 18 May 2007 10:49

I routinely use Confront herbicide on St Augustine to control mat chaff-flower weeds even though it is not recommended to do so. It is possible Confront may damage St Augustine in certain temperature / environmental conditions, but I have never had any problems using it, just make sure you do not exceed the labeled maximum tank mix / ratios. No guarantees – just advising you it works fine on my St Augustine. Good Luck!

[This message has been edited by TexanOne (edited 18 May 2007).]

fritomd – posted 18 May 2007 18:46

Thanks TexanOne and murquiza,

TexanOne I had a feeling that confront could be used and I do understand the potential for St A damage. I just wanted to hear that someone had used confront on St A.

thanks!

TexanOne – posted 19 May 2007 22:14

Fritomd,

Another option you may want to consider is using a commercial-grade herbicide such as Trimec (mixture of 2,4-D, Dicamba, and MCPP). Trimec is excellent at controlling most broadleaf plants in southern turfgrasses with little to no risk of damaging the St Augustine.

http://www.pbigordon.com/professional/page.php?id=301

An interesting note about Confront in St Augustine: I originally purchased Confront to control St Augustine in Zoysia turfgrass, but it did not damage, or control the SA at all – even at 150% recommended tank mix doses. However, it should be noted that herbicides can produce different results with different St Augustine cultivars. My St Augustine is a non-commercial, native Texas-Common variety that seems to be little affected by any herbicides except glyphosate (Roundup active ingredient). If you have a commercially patented St Augustine variety (i.e. – Raleigh, Palmetto, etc), I would recommend you try spraying a test patch to determine the toxicity before wholesale spraying the entire area.

energyrick – posted 20 May 2007 13:04

I have used corsair on SA and centipede with good success. It is slow to kill so be paitient. The buttonweed will discolor before fading on out into the sunset.

wrivers – posted 25 May 2007 11:56

quote:Originally posted by TexanOne:I routinely use Confront herbicide on St Augustine to control mat chaff-flower weeds even though it is not recommended to do so. It is possible Confront may damage St Augustine in certain temperature / environmental conditions, but I have never had any problems using it, just make sure you do not exceed the labeled maximum tank mix / ratios. No guarantees – just advising you it works fine on my St Augustine. Good Luck!

[This message has been edited by TexanOne (edited 18 May 2007).]

TexanOne,

Confront (clopyralid, specifically) is no longer labeled for use on residential turf due to its persistance in clippings and potential to contaminate groundwater. This has been in effect since 2002. FYI.

wrivers – posted 25 May 2007 12:01

quote:Originally posted by energyrick:I have used corsair on SA and centipede with good success. It is slow to kill so be paitient. The buttonweed will discolor before fading on out into the sunset.

energyrick,

At what rates are you using Corsair in St. Augustine? Have you used any tank mixes (Trimec Southern, Certainty, etc.)? Any discoloration? Thanks.

fritomd – posted 25 May 2007 19:15

I have just received my Confront and Spotlight. I plan on testing them against each other in a controlled trial.

Many of us realize that Confront is not labeled for residential uses. A rep at Dowagro confirmed to me in some many words why. Apparently, in the NW USA there is a practice of recycling grass clippings for compost. Confront will breakdown rapidly in soil, but slowly in grass clippings. There were some loses of vegetable plants using the contaminated compost. I have only heard speculation regarding ground water contamination from some “organic” sites. It makes no sense that residential use will conataminate graound water more than use in parks, playingfields, golfcourses, etc.

So, Dawagro changed the labeling to exempt residential uses related to the potential liability associated with grass clipping compost. I am OK with that. Please let me know if anyone has any contradictory information.

I will give followup later on the results of my primitive trial. BTW, I am nearly certain my St A is tex common.

seed – posted 26 May 2007 15:02

Both Confront and Spotlight are harmful to St. Augustinegrass.

Confront has two active ingredients, trichlopyr and clopyralid. Although the ingredient clopyralid (also in the product Lontrel formerly labeled for St. Augustinegrass lawns) does not damage St. Augustinegrass, trichlopyr does damage St. Augustinegrass.

Spotlight, active ingredient fluroxypyr, was once labeled for use in St. Augustinegrass but the manufacturer responded to injury problems by restricting it from use on St. Augustinegrass in Florida.

Phil

fritomd – posted 26 May 2007 18:24

I will let you know what happens.

I am applying the concentrations specified on the label for both products (as soon as the rain subsides).

I do realize Confront is not labeled for St A, however there are eneough anctedotal reports of efficacy without damage for me to apply to a heavily infested area.

I did discuss with the Dowagro rep about the Spotlight labeling regarding Florida St A turf and the lack of warning for St A in other states. He was very noncommittal and just referred me to the labeling which delineates a concentration for St A in states other than FL. My assumption is that floratam is less tolerant of spotlight.

Thanks for the input. Anyone else have any thoughts or experience with Diodia V in St A eradication?

TexanOne – posted 31 May 2007 00:44

Fritomd,

Just to make sure, are you positive you are dealing with Diodia and not some other weed? Matt Chaff flower (Alternanthera sp.) is very similar in appearance and is a serious pest in Texas lawns.

http://en.wikipedia.org/wiki/Alternanthera

fritomd – posted 31 May 2007 18:43

TexanOne,

I am not sure of anything, but I have been trying to figure out this weed for over a year. None of the “experts” in Dallas had any idea except to say that it was a “broadleaf” and could not be eradicated. I finally started posting a photo of the weed on forums until someone ID’ed it. Upon follow up, it sure looks good for Virginia buttonweed. The Alternanthera is not as good a match.

This weed is voracious and has a tremendous survival advantage over St. A. Yesterday the weather cleared and I treated three areas with atrazine, confront, and spotlight. I have also got a half dozen specimens growing in pots and treated three of them also.

I will post follow up in 2,4,6 weeks.

thanks

hankhill – posted 31 May 2007 23:14

Sounds like you need some of TexasOne’s superman strain of St. Augustinethat’s MSMA resistant. Is that stuff on sale yet?

[This message has been edited by hankhill (edited 31 May 2007).]

TexanOne – posted 01 June 2007 03:55

Hank,

I got a kick out of your comment; but even the “super” St Augustine gets weeds from time to time! Matt chaff flower (Alternanthera sp.) is the weed that causes me the most problems. That weed can take over large areas of anything if left unchecked.

By the way, the super St Augustine has developed a slight, non-debilitating case of SAD in the past 9 months and that in itself makes it totally useless for commercial development. I’m still going to keep it despite it’s known SAD susceptibility because it still uses less water than the native Texas shrubs, and looks good doing it. I planted a flat of this stuff at my in-laws lake house at Lake Buchanan and it took off like a rocket and is symptom free. By the way, if you want some of this super stuff, I have a couple of flats to give away – I can’t market it anyway.

The certified Raleigh SA I bought last year has developed symptoms of SAD, though it has reportedly never developed a case of SAD and is supposedly immune. I am beginning to believe any St Augustine can contract the SAD virus at this point. I’m still collecting samples of SA from various places in West Texas (abandoned, non-irrigated yards and fields) and all of them are very promising. I am however, a little more reserved about claiming SAD resistance until a few more years of real-world field-testing. Some people like me just have strange hobbies…

dryoung – posted 02 October 2011 14:06

In case you are still for a good answer, here is a Virgina Buttonweed tip from Randy Lemmon who is a whiz here in Houston:

http://www.ktrh.com/pages/gardenline-virginiabuttonweed.html#