Laurel.. Black stuff on leaves

Discussion in 'Trees, Shrubs and Roses' started by chloe3789, Sep 28, 2011.

  1. chloe3789

    chloe3789 New Seed

    Joined:
    Jun 24, 2011
    Messages:
    28
    Likes Received:
    2
    Location:
    Canada
    I have a Laurel tree by our front door, and it has black flaky stuff on a lot of the leaves. At first I thought it was dirt, but now I am not sure.
    I`m wondering what I can do to cure it, or if it`s diseased and should be cut down.
     
  2. Loading...


  3. lukeypukey

    lukeypukey In Flower

    Joined:
    Feb 11, 2011
    Messages:
    610
    Likes Received:
    224
    Location:
    grimsby uk
    it could be leaf blight which alot of laurels suffer from and is a kind of fungus. unsure on how to treat this as i've never had too. im sure there will be info on the internet somewhere. hope this helps
     
  4. eileen

    eileen Resident Taxonomist Staff Member Moderator Plants Contributor

    Joined:
    Feb 7, 2005
    Messages:
    29,088
    Likes Received:
    6,277
    Location:
    Scotland
    Your Laurel could be affected by Sooty Mould Chloe. It is frequently noticed on leaves of evergreen shrubs such as camellia, rhododendron and laurel. This is the excretion of laurel aphids, soft-bodied, pale-green insects that damage leaves by blocking light and reducing photosynthesis. They suck sap from the leaves and secrete a sweet honeydew which drips onto the foliage and the sooty mould grows on the secretion.

    I know it is essentially a fungal problem but it doesn't need to be treated with fungicide. Sooty mould actually indicates there is an insect pest, such as white fly. These are often found on the underside of leaves, especially during the cooler weather.
    To treat white fly use an oil based spray. Use about a cup of ordinary cooking oil, a half a cup of water and a tiny amount of ordinary washing-up detergent. This is known as white oil. Put it in water, so it's about 40 parts water to one of this mixture. Stir it up and spray it on.
    Remember to get good coverage of the leaves so that you get the white fly. It smothers them and they die. For a smaller white fly problem you could try a commercially available, yellow, white fly sticky trap. White fly are attracted to yellow and they stick onto the trap. To make your own use a yellow ice cream container and smear it with Vaseline or cooking oil.
    I hope this helps you out a little.
     
    Frank likes this.
  5. carolyn

    carolyn Strong Ash

    Joined:
    Apr 13, 2011
    Messages:
    9,332
    Likes Received:
    4,855
    Hi Chloe, I agree with Eileen, check for an insect infestation. My first guess is aphids. they excrete a sweet sugar like residue that mold grows on and then the leaf looks black and dirty. You could try spraying a soapy warm water spray on the bush and then spraying it off with a garden hose to get rid of the "dirt", also. This will also help to get rid of any pests on the bush if you spray a fairly hard spray of water on the bark, in crevices and on both sides of the leaves. I have seen a fair number of white fly this fall and they leave immediately if the plant is disturbed and then settle back in as soon as you go away. So they are a little harder to really see when you go to look for them. The sticky traps are a good idea, to put up, to quickly notice when there is a problem starting. aphids don't really move unless they are in the wing stage of their life. Most of the ones that you see are in the nymph stage and easy to identify. Good luck.
     

Share This Page