Occasionally, a fence is not enough to keep out intruders.
However, a cactus enhancement will certainly do the job!

This photo was taken by a Hasselblad 500C medium format film camera with a Carl Zeiss Distagon 1:4 f=50mm lens and a Hasselblad/63 1xHz-0 drop in filter using Kodak Portra 160 film, the negative scanned by an Epson Perfection V600 and digitally rendered with Photoshop.