In case you did not see the posting at Horse Hill it is closed for Mountain biking and horses due to mud. I had not initially see the sign on the Kiosk and started up the hill and turned back as it was quickly apparent that the ground is no longer frozen and ridelable. There is a sign posted (thanks Matt for putting the sign up). I met one of Horse Hill perserves neighbors (Roland who is a super nice guy) and discussed that maybe another notice can be put up on the trail head sign in case people (like me) miss the sign on the Kiosk.
happy road riding until the mud is gone!! :-)