I once took a lichen class and it was so inside baseball, I mainly came away thinking "Well I guess I'll never learn how to identify lichen." But every now and again, I'll still try.
After a wet camping trip to the Mt. Baker area this weekend, came back to google the most obvious description of the below two lichen ("cabbage leaf lichen!" "circular black lichen!"), resulting in these as my primary guesses.
Porpidia crustulata? aka concentric boulder lichen? Maybe?
Lobaria pulmonaria? aka tree lungwort aka lung lichen aka lung moss aka lungwort lichen aka oak lungs aka oak lungwort? Perhaps?
If so, apparently it might have medicinal purposes: "A hot-water extract prepared using this species has been shown to have anti-inflammatory and ulcer-preventing activities."
Also: "L. pulmonaria has also been used to produce an orange dye for wool, in the tanning of leather, in the manufacture of perfumes and as an ingredient in brewing."