Question
what is the best way to treat scale in my hollies, they are infested with scale, will they recover, they are presently leafing nicely. but a presence of black residue covers the leaves with white lines also present. thank you

Answer
Don:
There is an insecticide that you may try called BAYER ADVANCED GARDEN TREE AND SHRUB INSECT CONTROL.  It comes in a blue container, mixed with water and applied to the soil under the plant-according to the directions.  The black residue (called sooty mold)sounds like the result of the insects. Check in with your garden cneter/nursery for the specifics.

Regards

Steve