A little more follow-up:
If Glenn hadn't mentioned Seven, and I had learned that my pine had mites, I would have reached for the Kelthane -- a well-known miticide. But it turns out that these pine mites are different from, say, red spider mites, and the treatment is different. My web research found this link:
http://www.ext.vt.edu/departments/e...s/eriophyd.html
which seems to refer to the kind of critters I've got. Interestingly, a stand of pine may have these mites at low levels normally, but they become a problem when a tree is stressed. Perhaps by taking my nishiki pine out of the sun I caused it stress and the mites took off!
Big spraying today, on my other pines as well. We'll see what happens. Again thanks to all for looking in on my problem.
Barry