Disease or insect issue with cherry laurels
Two of our cherry laurels are losing foliage and appear on a trajectory toward death. The cause appears to be something - disease or insect - that presents as white spots on the branches. Included with this message are two photos, one taken of an entire shrub, the other showing the white spots. Can we treat the problem or do we need to pull out the infected shrubs to prevent this from spreading?
Montgomery County Maryland
This is white prunicola scale which occurs on cherry laurel and flowering cherry, too. Scales are insects with protective covers like a turtle shell. Wait until the shrub is dormant, then use a stiff-bristled brush (not wire) to knock off as many of the scales as you can. This also serves to rip the covers off the scale, exposing the scale’s body underneath to pesticide spray. Spray with a dormant oil. If you see the tiny salmon-colored crawlers (juveniles) in June, spray with insecticidal oil or soap.