Although nothing replaces having your trailer’s soundness regularly evaluated by a professional, to give a preliminary check to your older trailer’s floorboards, try the old cowboy ice pick trick.
To start, take an ice pick and ram it into the floorboards in key areas, such as where your horse stands and where he urinates. If the wood is still sturdy, the ice pick will stand strong like a tree. If the floorboards are starting to rot, you’ll be able to “wobble” the ice pick back and forth and side to side. Test the floorboards from the top and bottom, and remember that old trailers—like old cars—need regular checks, repairs and maintenance.