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white powdery oval (worm shaped) on back of leaves

Posted by gardenaire 8a Vancouver BC (My Page) on
Sun, Jul 28, 13 at 21:03

I have a shrub in the yard that has masses of white fuzzy (powdery) shapes on the back of the leaves. I suspect there may be a bug under the fuzz but haven't seen one yet. When I rub the leaf the white shape rubs off like powder.
As well, and I'm not sure if it is connected....there is a black residue/mold? on the tops of the leaves. I've done a ton of google searches and image searches and have found nothing that matches.
Does anyone know what this might be and how to deal with it?
Many thanks!! Deanne

Follow-Up Postings:

RE: white powdery oval (worm shaped) on back of leaves

Looks like wooly scale

RE: white powdery oval (worm shaped) on back of leaves

This is cottony scale, a plant sucking plant pest.
The white stuff are egg sacs, each one filled with many tiny eggs.
The scale insect is probably dead by now -- it's the small tan thing at one end of the egg sac.

The black stuff is sooty mold. It's an everpresent fungus which colonizes the sticky stuff the scale insects excrete while they are feeding.

Direct hits of insecticidal soap can help limit the scale insects and help loosen the sooty mold so that you can wash it off with a forceful water spray.

RE: white powdery oval (worm shaped) on back of leaves

Thank you ians_gardener and jean001a! I appreciate your time. I checked both insects online images and we definitely have the cottony scale. I will apply the insecticidal soap and hope for the best.

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