My brother is camping in NW Colorado and had a visit from a state employee telling him that he was on State Trust land and had to move. Yup, he had to move 500 ft to get on BLM land. What I learned is that there is an 85-page brochure on the rules for using Colorado state land. In general: “Lands enrolled in the State Trust Lands Public Access Program are open to hunting and fishing only, and where specifically authorized, wildlife viewing. General recreation such as hiking, horseback riding and dog walking are not allowed under the program.” You need to have a fishing or hunting license to be on State Trust land, but camping isn't generally allowed.
The brochure also covers the rules associated with State Wildlife Area (SWA). To be on SWA land one needs to have a fishing or hunting license, or a State Wildlife Area Pass ($46.48)
FYI My digital property ownership map has the land labeled as STL, in other states it is labeled as State Trust.
The brochure. It is labeled 2021, but this is the one on their web site. lands.pdf (state.co.us)
Gosh, I wish it wasn't so hard to follow the rules with all the various federal lands and state lands each having their own rules.