? About glyphosate (round up)

Discussion in 'Pesticide & Herbicide Application' started by nt1, May 2, 2007.

  1. nt1

    nt1 LawnSite Senior Member
    Posts: 298

    How long after application does it take for round up or glyphosate to be effective?

    We had a wave of heavy storms and rainfall come through about 3 to 4 hours after an application to st. augustine.

    Grass is growing fast and temperatures were in the low 80's.
     
  2. indyturf

    indyturf LawnSite Bronze Member
    from Indy
    Posts: 1,873

    how long ago did you apply? I have sprayed round up and thought it wasn't working almost a week after applied, then you go out the next day and every thing has turned brown. it really depends on temperature and the weather.
     
  3. nt1

    nt1 LawnSite Senior Member
    Posts: 298

    The round up was applied today & and heavy rainfall came about 3 to 4 hours later.
     
  4. indyturf

    indyturf LawnSite Bronze Member
    from Indy
    Posts: 1,873

    should be ok, but you will know for sure in a week! was it roundup pro? I think its rain-fast in an hour and works faster than regular roundup.
     
  5. nt1

    nt1 LawnSite Senior Member
    Posts: 298

    Yeah, the label states rain or water will not decrease effectiveness after one hour.

    Still find that hard to believe, quess I will know in a week.

    I am scheduled to put in some flower beds next week where the round up was applied ( 900 sq ft. ).

    I do not want to postpone this job for another week If I have to reapply again next week then wait another week and so on.
     
  6. ampeg76

    ampeg76 LawnSite Senior Member
    Posts: 297

    looks like texas temps are going up within the next week, so if sufficient chemical was applied you will know by then!

    did you use a adjuvant?
     
  7. teeca

    teeca LawnSite Bronze Member
    Posts: 1,202

    i've applyed in the rain and it worked fine, indyturf is correct, it does take a GOOD week before you see any resualts. the round up pro has diquat add and it gives visual resualts in a day. i use the regular round up and add my own diquat (reward, or weed plex if you shop at lesco) to it.
     
  8. Ric

    Ric LawnSite Fanatic
    Posts: 11,957

    Teeca

    What is the ratio of your Diquat to Glyphosate? Too much Diquat and you loose the systemic effect of Glyphosate. I will post if your ratio is the same as the ratio I use or different. However most people I talk with, I believe are using too much Diquat in their mix ratio. It takes a very little Diquat to speed up brown out of weeds. Monsanto researched this mix very long before coming up with the granular formulation of Quick Pro that works. BTW I am not sure my mix ratio is the best for total systemic kill.
     
  9. teeca

    teeca LawnSite Bronze Member
    Posts: 1,202

    i use round up @ 2.5% (3-3.5oz per gal) in a 4gal backpack sprayer and add 1oz reward and 1-2oz of a surfactant.
     
  10. Ric

    Ric LawnSite Fanatic
    Posts: 11,957

    Teeca

    Just as I am guessing. IMHO your high rate of Diquat is blocking the Glyphosate from being systemic. You could drop the Glyphosate and still get the same response from that mix. At one time I was using 0.5 oz of Diquat and 3 oz of Glyphosate and was still blocking the systemic action. Diquat burns the plant so fast the the Glyphosate doesn't have a chance to get in. BTW the Surfactant is helping the Diquat and not the Glyphosate. Just about all Glyphosate brands already have Surfactant in them. Aquatic Glyphosate is the most common not to have any surfactants.

    In a 25 gallon spot sprayer I am mixing 75 oz of Glyphosate, 3 oz of Diquat and 4 lb of Ammonium Sulfate. I see a response in 3 to 5 days. No this is not as fast as Scythe but it is a lot faster and a more complete kill than you get with either Diquat or Glyphosate as stand alone or mixed products at your present mix rate.
     

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