I do not know if this is true, but i have read that one should wear a bright blue shirt (like the ugly tarps) in the woods, because that color does not appear anywhere in nature's color scheme, except some flowers.
I'm gonna go with not true - at least the part about bright blue not being on nature's pallet...
I LOVE that picture!
However, blue is a very rare color among natural vegetation, rocks, dirt and lots of other things found in nature. Except for the sky and water, of course...
When I was a kid there was one and ONLY one correct color for anoracks: A bright orange color. Apart from the hunting issue I can see arguments for both being clearly visible and not hurting the eyes of others (or yourself).
My bivy bag (described
here ) is extremely well camoflagued. Which makes sense for hunters, but not really for use in an emergency. After 15 years of wear and tear I'm putting a replacement on my Cristmas Wish list - and I'm considering if that should be a bright orange color. (But that orange color really HURTS my eyes...)
Solution (as others have noted): Bring a reflective vest. New regulations (in Europe, at least) dictates that any vehicle should have a reflective vest easy accessible. Which means that vests are sold EVERYWHERE. Cheap, too, and ultra lightweight.