Need help Identifying a “Mystery weed”

Jeff K – posted 09 June 2006 16:43

I had about 3,000 sq/ft of my St.Augustine lawn die out last winter. The weeds took over rapidly.This is a pic of the worst offender.I sprayed the whole thing with Roundup and re-plugged St.Augustine.It did die from the Roundup, but it is rapidly coming back. Much faster than the plugs.I’ve drug this weed all around town and get “thats a weed” “thats crab grass” “thats alligator weed”.I have to figure out how to kill this stuff.

http://jkozloski.com/pics2/trash/Weed%20two.JPGhttp://jkozloski.com/pics2/trash/Weed%20two%20.5.JPG

BuckinNC – posted 10 June 2006 05:31

Go to: http://www.turffiles.ncsu.edu/Home/Default.aspx

Click on Decision Aids, select Turf and Weed ID and take it from there. After you have identified your weed(s), go back to Decision Aids, select Weed Management and figure out how to kill them.

hankhill – posted 10 June 2006 23:55

I’m by no means an expert, but from what I have learnedprotecting my St. Augustine lawn, I’d guess it’s crabgrass.

You’ll need a post-emergent herbicide that’slabeled for crabgrass control.

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Grassguy – posted 17 July 2006 00:05

looks like virginia button weed

jr – posted 18 July 2006 18:12

looks nothing like virginia buttonweed for heavens sake. thats clearly crabgrass. tell us what its in and we will tell you how to fix it.

Grassguy – posted 18 July 2006 20:14

from the pic its hard to tell because I cant see the vernation, auricle-(crabgrass has none), ligule or the collar. There are a couple of other weeds that look similar to crabgrass.I forgot to ask JR, Is Buttonweed a dicot or a monocot? And,what where the identifying characteristics that led you to the diagnosis of crabgrass?

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Grassguy – posted 19 July 2006 11:09

Hey Jeff K, what ever it is you can kill it easily if its not growing among desireable turf. Its to hot(atleast in my area) to spray selective herbicides. if its to hot where you are wait till the tems drop to under 85 and spray it with trimec, Drive75, or any selective ester type herbicide. The identifying characteristics used to properly identify a weed are not clearly visible in the PIC, whether its a monocot or a dicot trimec will kill it. its manufactured by PBI gordon. also, if the weed is just growing randomly around the yard and there is no danger in spraying desireable turf spray it with round up. when using herbicides more is not better. when doubling the strength this kills the above ground portion of the plant before the herbicide can move into the root zone for a complete kill, then the weed returns. mix at specified rates.

[This message has been edited by Grassguy (edited 19 July 2006).]