Teacity on a Newer TTTF Lawn

Discussion in 'Pesticide & Herbicide Application' started by Hineline, Mar 12, 2019.

  1. Hineline

    Hineline LawnSite Senior Member
    Messages: 869

    Last year a member posted about gray leaf spot on newer TTTF that had included using Tenacity as a pre. I may have had much the same on a new lawn in Sept, 8 weeks after using Tenacity as a pre. Has anyone else seen any problems using Tenacity on a newer TTTF lawn? I am going to go after poa triv suppression on a TTTF lawn that is about 1 1/2 years old in a larger area of the lawn.

    Moderator, please edit the header to read Tenacity.
  2. Rockbridge Lawn Care LLC

    Rockbridge Lawn Care LLC LawnSite Bronze Member
    Messages: 1,085

    what was your first application rate? then the second?

    I found Tenacity is "OK" with POA...nothing is "great" with POA......
  3. Hineline

    Hineline LawnSite Senior Member
    Messages: 869

    I did one 5K bag of Scotts Starter with pre on about 5 K or the standard rate. You are correct about Tenacity on triv. Not great.
  4. ArTurf

    ArTurf LawnSite Fanatic
    Male, from Ark
    Messages: 5,790

    I'm not a cool season turf guy but I don't see the connection between the fall app of herbicide and grey leaf spot. Are you thinking the Tenacity may have contributed to GLS?
  5. Hineline

    Hineline LawnSite Senior Member
    Messages: 869

  6. Delmarva Keith

    Delmarva Keith LawnSite Senior Member
    Messages: 536

    Never had a problem with Tenacity on unstressed TTTF. Did get some bleaching on stressed areas but no permanant damage.

    To go after poa triv, mix Tenacity with triclopyr. It will burn off the top growth pretty effectively. It will grow back. My guess is you’ll have to spray over and over to deny it carbs to kill it, but you’ll run out of allowable apps before it’s killed.

    Here’s a pic of the burndown from last Fall (it is back now — smaller patch but it is back). Note that the TTTF around the patch is healty and unaffected.

  7. Delmarva Keith

    Delmarva Keith LawnSite Senior Member
    Messages: 536

    Also, I watched the video in the GLS thread. A theory that comes to mind: he sprayed azoxy early on and the GLS is resistant to azoxy. The azoxy wiped out all the competition of the GLS and GLS flourished, killing his juvenile stand of fescue. Hindsight is 20/20 but if he mixed the azoxy with the thiophanate-methyl on that first app and stuck with it until the GLS was dead, it might have worked.
  8. Hineline

    Hineline LawnSite Senior Member
    Messages: 869

    Good analogy!
    Also, the way I am attacking triv is how I attacked bent last year which is to apply the granular version. My supplier carries the pro version of Scotts pre with Tenacity. What I found was a good 3-4 weeks of whitening suppression along with a burst of nutrients for the desired grasses. I just can't get back for a respray on a timely fashion. This worked well on bent so I am moving on to triv next.
    Delmarva Keith likes this.

Share This Page