Cat Picket Fencing

Erica sent me this picture of cat fence pickets. They look easy enough to make. The problem is where would I put them?

Perhaps I could replace the hemlock trees in the front of the house by the road. Our sewer backed up last week and the rotor rooter man found the pipe filled with hemlock roots. It cost me $400 to fix and the cellar is still full of stinky muck.