From the University of Nebraska-Lincoln,

"Prune out heavily infested branches, as appropriate. Dormant oils are not effective, as scales are in the egg stage beneath female shells. Monitor in June to detect newly hatched nymphs and apply oil spray, insecticidal soap or insecticide.

You can try the spray on a branch or two, but I don't think it will work. Prune (and burn the branches or trash them) and then spray the nymphs when they hatch.

Steve

Jace, can we see a picture of your scale? Some species are more treatable than others.

if its ornamental.. and you dont want to do what i suggested in the other concurrent post..

then look into bayer systemic tree and shrub .. which is labeled for scale ...

one shot .... and you are done..

unless you are an artist with the pressure wand.. i dont know how you can do it.. without peeling off all the bark ...

this is an EXTREMELY problematic tree ... with the potential to suffer from all kinds of problems as per the link ...

i dont understand why you are so interested in saving it ... but that is your choice ... fer sure ...

if beech grow in your area .. you would be better off planting a copper or riversii beech and enjoying it carefree for the next 100 years.. rather than dealing with problem tree ... [presuming we are talking about the purple leaf ornamental]

good luck .. play with it.. experiment.. and my point is.. simply.. get rid of it.. before investing too heavily in it

ken

Here is a link that might be useful: link