Went to my orchard yesterday and found somebody had left a utility trailer all the way in the back. I called the cops and they said what do you want us to do, if its on your property then keep it or have it removed, we have no reports of any stolen trailers in the area. How do I go about obtaining this legally? I am in California.

Are there tags on the trailer? If so, have you tried to contact the person it's registered to?

Is there a serial number?
I'd record that number, if any, and take it to your local registration agency and see if they can assist. If it has a record, they'll be able to tell.

If you want to OWN it,keep it.

Possession IS 9/10th's of the law.. or so I am told.