Root of the Problem Traditional Cache

Enjoy your walk down the old river road while you search for this cache.  An easy walk to GZ, the difficulty begins once you arrive! The cache is located in North Park. Park hours are dawn to dusk. Please do not search for this cache when the park is closed.

A bison tube, hidden in a host.  Given that you are in the woods, and we hate micro's hidden in the woods, we thought we'd give you a few more cryptic clues.  After walking a quarter mile to this cache, it's the least we can do!   The cache host is natural.  Naturally, you'll need to figure out what isn't natural.  Good Luck. No spoilers please!