Pacific NW woolly bear help needed

[Allyn Weaks]

Seattle, WA.  Last month I posted about hatching some caterpillar eggs
that had been laid on himalayan blackberry, Rubus discolor.  Well, they've
turned into a handsome set of woolly bears.

I tried raising 4 on thimbleberry (Rubus parviflorus), and 11 on
blackberry.  One from each group either died or vanished.  The ones on
thimbleberry are surviving but not thriving.  They're only about 2/3 the
size of the vigorous blackberry bunch, and not nearly as woolly.  The
average size of the blackberrivores is about 5 cm, and they're now eating
about 1/2 of a good sized leaf per 'pillar per day.  They're a nice
cinnamon color, with varying amounts of black at the front, roughly
through the thorax segments.  Heads are yellow to cinnamon, no prominent
markings.  I'm not certain that I've counted all of the instars properly,
because there is some spread between individuals and they mostly eat their
old skins, but I think they're 6th instar.  Unfortunately I don't have a
way to get decent pictures, especially of proleg details (there are 8 red
crotchets in a row, if that helps) and warts.

>From _How to Know the Immature Insects_, and counting warts on the 6th
through 8th abdominal segments (in addition to the general woolly bear
appearance), they're clearly Arctiinae.  But I haven't had much luck
getting further than that yet.  Haven't found anything on the net about
tiger moths in the pacific NW, and the university of washington library
system set us back to about 1985 when they moved to a web-based interface
that doesn't let you search for combinations of fields, either for books
or the journal databases.

I need some help to know what to provide for them to pupate if that's how
they overwinter, and how to overwinter them (seems a little late for
another generation this year, but maybe not impossible--it's often warm
into october.)  They certainly can't count on being frozen here!  I don't
want to just turn the caterpillars loose in a briar patch, because I
really want to see the adults, and probably send one somewhere for an ID
to species.  Pointers to references, be they books, journal articles, or
web sites, would be great.

Many thanks!
-- 
Allyn Weaks  allyn at teleport.com  Seattle WA, USDA zone 7/8
Pacific NW Native Plant Gardening: http://www.teleport.com/~allyn/natives/
My email address is in WA State.  If you don't want to pay me the 
$500 I can legally collect, don't send me UCE/spam.