The problem with the 'stashing the pack' approach is 1. I don't trust it 2. Mice ARE a big problem and can easily chew through a pack to get at the oatmeal 3. Hanging packs is actually a lot of fun.  

I use the horizontal rope, two pulley approach described elsewhere on this site.  Tip - I toss a drilled baseball with light parachute cord to thread the hanging rope over the branch.  Easier and safer than trying to tie a rock to a cord.