This as in 2013. Maybe for reasons you mentioned and just because there is so much which states cannot afford to maintain.
This is old: https://www.sfgate.com/news/article/National-parks-pot-farms-blamed-on-cartels-2560508.php
Thanks. I live in the west and the fed owned land is a huge problem. Lots of poverty surrounded by land which cannot be touched. So, lots of dope growing and crime.