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sooty mold application

Discussion in 'Pesticide & Herbicide Application' started by grassmasterswilson, Feb 1, 2013.

  1. grassmasterswilson

    grassmasterswilson LawnSite Platinum Member
    from nc
    Posts: 4,468

    I've been asked by a local landscaping company to do some applications for sooty mold on a few customers they have.

    I will be applying a mix of hort oil and imicloprid in late winter(late february or early march) to help "wash" and prevent future infestation.

    Am I on the right track? I haven't been asked to provide a price as long as I was in reason. I would just figure time + materials. I Don't do much shrub treatments so are most of you figuring shrub and lawn time to be the same cost? Would you charge by shrub...$5 for large and $3 for smaller?
     
  2. ted putnam

    ted putnam LawnSite Platinum Member
    Posts: 4,531

    Sooty mold is a fungus of turfgrass. One that causes no damage.

    Imidacloprid is an insecticide along with hort oil. Hort oil is great for smothering scale on ornamentals but has no fungicide properties that I am aware of. Imidacloprid works systemically aginst many types of insects in turf and ornamentals.

    Are you talking about mildew that grows on the honeydew that is left behind by feeding insects in ornamentals??

    I'm lost........
     
  3. greendoctor

    greendoctor LawnSite Fanatic
    Posts: 8,802

    Sooty mold is the result of heavy infestations of honeydew producing insects such as scale and aphid. The mold forms on the honeydew. When the insects are controlled, the honeydew stops, the mold is no longer fed and it flakes off. On dormant shrubs and trees, copper or lime sulfur is directly toxic to the honeydew. To prevent the problem next year, those trees and shrubs should be treated with imidacloprid applied as a soil treatment right before the plant resumes active growth.
     
  4. grassmasterswilson

    grassmasterswilson LawnSite Platinum Member
    from nc
    Posts: 4,468

    Thanks. That was my plan to prevent the aphids or other pest. He said that mixing dish soap or oil would help to wash off the mold once it rains. Everything is cold and new growth will start in the next month or so.
     
  5. greendoctor

    greendoctor LawnSite Fanatic
    Posts: 8,802

    I am really not in favor of spraying imidacloprid. It does not last long enough. In addition, repeated sublethal applications due to mediocre spray equipment fosters development of resistance. I have populations of whitefly here that are very resistant to imidacloprid thanks to misuse of imidacloprid.

    Removing sooty mold can be accomplished by soapy water, followed by a rinse. Detergents left on plants can cause damage worse than the problem you are trying to treat. Oil works, but it is because it kills what is feeding the sooty mold. If the plants will tolerate it, you can try Kocide. That is a broad spectrum copper based biocide,
     
  6. turfmd101

    turfmd101 LawnSite Bronze Member
    Posts: 1,268

    Since Imidacloprid absorbs much better in newly developing soft leaf tissue. Mid April to May rains should produce a better introduction into the soft tissue growth, as well as providing a better residual time frame for when insect population will be active.

    If the shrubs are kept sheared heavy during summer growth, keeping the soft tissue ( insects favorite) growth cut. Don't waste your time until late summer or early fall new growth.

    Treating sooty mold is treating an ugly effect from poor management.
    Granular imidacloprid won't be cost effective unless you can charge heavy $.
    Especially if drought, on top of proper irrigation management occurs. Not enough water to effectively break down the insecticide or provide proper growth for successful uptake. JMHO. Plus cutless granular will shut down new tissue growth cutting out desired pest target growth.
    Posted via Mobile Device
     
    Last edited: Feb 1, 2013
  7. greendoctor

    greendoctor LawnSite Fanatic
    Posts: 8,802

    Granular imidacloprid is usually only labeled for Nursery or turfgrass use. Unless you are talking about the now discontinued 2.5G. Label rates on that product were only effective for 6-8 weeks at best. The 0.5 G is labeled for control of white grub in flower beds and ornamental areas. The rate permitted is not even close to what is specified for the 75WP.

    I have had applications of imidacloprid wash out in heavy rains. Leaving me to "splain" why the treatment did not last as long as it should have. I prefer to apply when there is low probability of rain and control the irrigation as specified on the label.
     
  8. turfmd101

    turfmd101 LawnSite Bronze Member
    Posts: 1,268

    Applying merit granules, with knowledge that heavy rain is expected WOULD be foolish. Normal rainfall or adequate rain IS helpful.

    The target pest assumed are easily controlled with less aggressive insecticides. The fact that there has been no discussion on what type of plant material the merit would be used on, would explain the varied responses. Hibiscus vs crepe myrtle. Something with ongoing shoot growth ( always new soft tissue developing) vs season developed growth, shows... We need more info to adequately advise or we are all shooting in the dark. Instead of guessing what type of growth habit plants are being discussed. We are talking IN GENERAL to his SPECIFIC NEEDS. Foolish...

    Merit in any form at its lowest rates will easily kill aphids. Scales, different rates, different AI's and so fourth.

    Rain does not effect residuals of merit unless we are discussing soil insects. Weekly shearing with heavy fertilization effects residuals in ornamental. If an explanation of your failed application is RAIN. With all due respect,,, apply more wisely. In the end, merits main purpose will be to help insure populations will not get to a level of noticeable damage at the same time minimizing the potential for tons of ALL THAT BLACK STUFF.
    Posted via Mobile Device
     
  9. grassmasterswilson

    grassmasterswilson LawnSite Platinum Member
    from nc
    Posts: 4,468

    Thanks for all the info guys.

    Haven't had a chance to go by and look but the landscaper said it was mostly on camellias azaleas and maybe some gardenias. Just got the jobs and need to go look to make sure it is what he says.
     
  10. turfmd101

    turfmd101 LawnSite Bronze Member
    Posts: 1,268

    If you find camellias and gardenias. It will most likely be T- scale. If they are very BLACK. You'll find heavy activity. Most sooty found on azaleas is from some type of arbor raining down honeydew below on them. If you get azaleas black from lace bug, man you missed bleaching sign of things to come. In any case Green Docs hort mix with soap is the best remedy. Merit not great on scale for the $. Malathion will best suit bang for buck.
    Posted via Mobile Device
     

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