St. Augustine problem

Discussion in 'Pesticide & Herbicide Application' started by Stonewall, May 3, 2007.

  1. Stonewall

    Stonewall LawnSite Senior Member
    Posts: 280

    I have several instances of St. Aug. turning yellow then slowly dying. After a while, some of the runners will pull up easily, similar to chinch bug damage in that way. I don't see any evidence of insect problems, etc. Any ideas?
     
  2. RAlmaroad

    RAlmaroad LawnSite Silver Member
    from SC
    Posts: 2,185

    Stone: Is this happening NOW. I've seen it happen later in the season because of: I. Overwatering, 2. Over fertilization, 3. Lack of Iron.
    Tell me a little more as far a schedule, how much water, etc. Maybe I can help.
    Roy
     
  3. Stonewall

    Stonewall LawnSite Senior Member
    Posts: 280

    Yes, it's happening now. The ones I have in mind aren't irrigated so I don't think that's the problem. One I've fertilized and the other has had any fert. since last year sometime.
     
  4. RAlmaroad

    RAlmaroad LawnSite Silver Member
    from SC
    Posts: 2,185

    That's difficult--There is something called St. Augustine Decline (SAD). I do not know anything about it. Why don't you run it by the County Extention Agent.
    St. Augustine needs to be overdressed with some organic material such as a cow manure and compost mix. Chemicals deplete the soil of organic material by killing the organism that produce it (Small bugs, etc) Thatch build up could promote some fungas problems by roting the roots through heat buildup and moisture. I sorta link it to the SAD

    Finally, St. Augustine really likes its nitrogen during May, June, July. You've got to feed it 1lb.N/K. You might feed it and add about 10% Fe.. There is a warm earth relationship to cold temp that could cause the yellowing but in MS, I don't think it would be a problem. Try the Nitrogen and Iron and let me know if any help.

    Try this also on a small piece--sprinkle some ant crystals and water them in--Let me know the outcome
     
  5. Bigolbigun

    Bigolbigun LawnSite Member
    Posts: 11

    Ditto to what RAlmaroad said but you might want to try aerating also. I have seen the problem you have mentioned and have resolved it by aerating the yard.
     
  6. RAlmaroad

    RAlmaroad LawnSite Silver Member
    from SC
    Posts: 2,185

    Aeration gives those stolens someplace to grow. Just think about the habit of the grass. Great. How long had it been since you areated. Some say about three years. I generally have my few to bag their clipping instead of throwing them out to the side of the mower. Thatch buildup in the heat equals mold, fungas, and root rot.
    Keep posted,
    Roy
     
  7. txgrassguy

    txgrassguy LawnSite Gold Member
    Posts: 3,083

    I aerify all of my St Augustine residential sites a minimum of twice per year.
    Followed up with a Jrco spring tine rake mounted on a mower to break up the cores. The Navigator follows, bags everything and the customers really appreciate a soil turd free yard.
    On my really high end customers, I follow this whole process with a chelated iron application and these sites really stand out.
    However, these customers pay for the results.
    On troublesome St Augustine sites I pick up as new customers, insects have proven to be the initial cause of the turfgrass decline these customers are complaining to me about.
    Once I address the insect problem, the corrective course is what I described above.
    One benefit is that I am spraying contact fungicides much, much less now than I had been before.
     
  8. RAlmaroad

    RAlmaroad LawnSite Silver Member
    from SC
    Posts: 2,185

    Tex--I've used a product with Micro-nutrients with iron a couple of years now. Just trying it on the St.Augustine. Hopfully it will do as nice a job on it as it does the fescue. Overdressing with organic material should yield organism to attack the fungas--Don't know for sure, but I'm trying that approach. I'm trying to avoid as much contact stuff as possible as it will surly kill a lot of the organism that produce a healthy soil. Sand is such a B-ich to build up.
    There was a guy on the turfgrass site that wanted to know what were those long "stems" with St. Augustine leaves on them
     
  9. Roigator

    Roigator LawnSite Member
    Posts: 9

    I deal mainly w/ St. Aug. What you're describing can be many things. I would check for mole crickets. Sometimes a low population will cause such symptoms. Also check the pH of the soil. Make sure that it's btwn 6.5-7. It may also be take all root rot of st. aug. This can be treated w/ Azoxystobin (Heritage), or better yet Azoxy. + propiconazole (Headway). If the problem is seasonal and decline is very slow, you may have a plant-parasitic nematode problem.
     
  10. Stonewall

    Stonewall LawnSite Senior Member
    Posts: 280

    What are ant crystals?

    I will send off a sample this week. Isn't it a little early for mole cricket damage? I didn't see any tunnels.
     

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