Plum Yew – Scale Control
Q: I have some large plum yews that are infested with scale. I have been spraying with neem oil and have not seen much improvement. Is there a remedy to eradicate this insect?
A: Oil insecticides are usually effective on scale insects but plum yew has such dense foliage that I can understand why the neem didn’t work well.
I had the same scale problem on my plum yew and used a systemic drench that contained imidacloprid (click for sources). I got excellent results.