Cactus fence
Image:Acanthocereus tetragonus fence1.JPG|thumb|Acanthocereus tetragonus, laid out as a "living fence", rural area, Cuba
Image:Cactus fence, Dutch Antilles.jpg|thumb|A cactus fence in Bonaire.
Image:Cactus fence, House of Frida and Diego.jpg|thumb|A cactus fence in Mexico.
A cactus fence is a hedge or fence made of closely spaced cactus plants, sometimes with barbed wire or wood interwoven with the cacti.
Purpose
Such fences are inexpensive to develop in regions where cacti are common, and can provide an extreme deterrent to any but a determined human intruder. Often their primary function is to keep wandering large animals off a private property.Design
Sometimes, cacti are used as barriers without being formed into a structured fence. Prickly pears were imported into Australia in the 19th century for use as a natural agricultural fence and to establish a cochineal dye industry, but quickly became a widespread weed.Closely spaced columnar cacti such as Trichocereus or Mexican fencepost cactus can be used for more structured, space-saving fences.
In the American southwest, ocotillo stems are often set in the ground to form a structure similar to a cactus fence.