Addendum

The moth is a Pandora moth. Here's what Shapiro had to say:

Pandora Moth, Coloradia pandora (family Saturniidae). The larvae feed on needles of Ponderosa, Jeffrey and Washoe Pine and occasionally cause widespread defoliation. The life cycle takes two years and some areas have only odd- or even-year populations. The very large caterpillar has stinging spines. It pupates in the ground and in outbreak years the Paiutes would dig pupae by the thousands and eat 'em roasted--they're said to be very nutritious. I've seen hundreds of adults attracted to lights in NE CA and Nevada, usually at remote gas stations! There are a couple of much less common congeneric species, and Pandora also occurs in the Klamaths and the High North Coast Range; I've seen in at least S to Goat Mountain. Cheers...

Also, Sonora Peak is 11,459 feet.  So we made about 2000 feet of gain from the parking lot.  You know, I thought it was higher than 10100.  hmph.