With this one you've got two choices. First, you can find the Waterfall Trail cache, and the exact coords are written in its log book. (Well, as exact as they get out here.) Or, you can bring your compass, and use just the landmark bearings in the hints to make the find, in which case add a star to the difficulty. In fact, considering the signal quality out here - we did mention 'redwood canyon', right? - you may want that compass anyway.
The name? During the rainy season, this trail hosts more orange-bellied newts than we've seen anywhere else. Watch your step. If you're very lucky, you might also find a patch of chanterelle (Cantharellus cibarius) or black trumpet (Craterellus cornucopioides) mushrooms, both excellent eating! (Do NOT pick and consume wild mushrooms unless you have previous knowledge of the variety and make a positive identification.)
As of 5/9/2014, the cache is an ammo can. Along the way to the cache you will cross two bridges. The decking on the second is partly rotted - don't trust it! Cross on the edges where it's nailed onto the stringers, and you will be fine.