St. Augustine & Dallisgrass

Van – posted 05 May 2004 15:28

Location: Houston, TXTurf: St. Augustine

Dallisgrass is taking over my back-yard with over 40 clumps in different areas. I tried to dig out some clumps…some of the roots were very deep into the ground? I know I can use Round-up, and then plug in the dead areas.

Is this the best thing to do? Because if I spot treat all the dalligrass…I’ll have dead spots throughout.

What herbicides should I use in the Fall/Winter to control this so I dont face the same problem next year?

Thanks in advance.

ted – posted 05 May 2004 20:00

i’m really concerned about the correct ID on the dallisgrass. there’s dallisgrass, crabgrass, johnsongrass, goosegrass, etc. and guess what? they all have different herbicides that work on them. spot treating is the way to go, however, in this situation. if it is dallisgrass, then there’s no pre-emergent that works on dallisgrass, since it’s a perennial. so you’ll have to spot treat with the appropriate chemical.

cohiba – posted 07 May 2004 07:09

Van, If, in fact, it is Dallisgrass try the old MSMA as a spot treatment on it. There may be more grass than you think, waiting for a hand, under that dallisgrass. Try to ID the weed positively before you treat it saves time, money and aggravation.

Good luck……

Van – posted 11 May 2004 12:48

I think its definetly Dallisgrass. Looking at the pictures of the flowers/seeds….it does have the black silky hairs.

http://www.ppws.vt.edu/scott/weed_id/pasdi.htm

ted – posted 11 May 2004 20:55

great pics. yeah if that’s it, msma is your choice.

Van – posted 14 May 2004 09:46

A few people indcluding a rep from Scotts Lawn service has recommended not to kill it using Roundup and instead proceed on a path of making the grass helathier and thicker and thereby “suffocating” the dallisgrass.

Any thoughts on this?

ted – posted 14 May 2004 21:35

yeah, that’ll work, too. msma or roundup, though will eliminate the weeds- might not be so bad if you did small spot treat of sections. you have to ask yourself, given how thick st. aug. is- how did the weeds get there in the first place?

cohiba – posted 15 May 2004 06:49

Ted,Good point. If it were my lawn, I would juice up the turf and spot spray the dallisgrass with MSMA. Even at a lower rate. The MSMA will knock back the weed enough that the turf should be able to fill in quicker. If the turf is capable of filling in those areas.

Just my 2 cents…..

ted – posted 15 May 2004 15:44

st. augustine in houston, with all of the rain we’ve had, will definitely fill in over small (small!) roundup spot spray areas.