This was interesting and seemed worthy of sharing. This tree, owned by a client, was originally Rocky Mountain juniper. It had some of the worst scale infestation that I’ve ever seen, the Rocky Mountain foliage was so covered with it that it looked nearly white from a distance.
When we decided to graft on it I did warn my client that I was not sure of our success because the stock was weak. I think we did about 8 veneer grafts with itoigawa scions and 6 took. So we were happy and a bit surprised. What happened following that was even more curious.
I should say that we did not graft to get rid of the scale but to get rid of the bad foliage type. I do wish I had earlier photos of this so you’d be more likely to believe me, but none of the itoigawa grafts ever got scale. Not a single one. The itoigawa was even touching the infested original foliage, but the scale never transferred in the couple of years we were slowly cutting back the original foliage.
We also are approach grafting new roots on this tree, just to remove a long, boring section of lower trunk. That’s what the blue tape wrappings are about, holding the approach graft in place. That graft is taking well.
I hope this does not send the message ‘Got scale? Graft!’—for that would be a bit extreme. It was just a surprising benefit of what we wanted to do anyway. Spraying oil in May and June is usually a better (and somewhat less complicated) control for scale…