They did not initiate the question but it did arise. My first placement at a local park was about 50 feet up. I did not realize there was another geocache less than 528 feet away (they do not allow them closer that 0.1 miles to each other).
When the reviewer denied my first placement because of that rule I explained it was up in a tree and unless someone knew how to access it there was no conflict. He said they were preventing "cache saturation".
So, there you go....I learned to choose the tree first, get the lat/long, submit that location for approval and THEN climb the tree to place the cache.
Keep us posted, Nicko.