These are both very hard puzzles you've found there! I'll admit, I'm not good at them... But a thumbs up for the creativity of those puzzles.
Check out GCB14A and GCJN5Y. These I found while searching for possible cache finds in Hawaii. We were able to solve the 2nd one. LOL Needless to say, we were unable to attempt to find them. They were fun to solve though and sorely regret not trying harder to locate any more than we did.
Silva, of the forest
Beneath you, feel the Earth.
Above you, feel the Sky.
Around you, feel the presence and the Power
of the Trees!