[fwdude]

I'd guess that as long as it's accessible to the public without well-posted signs and/or barriers, you'd have a hard time proving trespassing.

[Boogieman]

Yep. If you want it to be private, it’s your responsibility to make a reasonable effort to keep the public out.

[Lonesome in Massachussets]

I'd guess that as long as it's accessible to the public without well-posted signs and/or barriers, you'd have a hard time proving trespassing.

If it's accessible and not posted, an easement had been created and you'll never get to block them, or pretty much anyone else.

[cripplecreek]

I live on a public street that they skipped. Course it doesn't exactly look like a street aside from the street signs.