Lad, Orthene is tough stuff. It's highly toxic to bees.I've talked to lots of folks about scale and once it get established it's almost impossible to get rid of. I suggest you contact a good landscape company, one that has folks on staff that are certified in the use of pesticides. There are products on the market that are labeled for use by professionals that are not available to homeowners. I would also contact your county horticulture agent at your county extension. Google county extension along with the name of your county. Good Luck and Happy Yardening, Nancy.