Re: Lower Mountain Fork
#20 or so. I have never had to go smaller. But there are times you need #22 ish according to locals.
Other Terrestrials.... There are few hoppers. Plenty of crayfish<= (hint hint)
Wooly buggers work well..... In olive.... DUH. But I wouldn't be afraid to take a whole box a little more brown(what i have seen in the creek).