In response to Brian Tasseys' question about bear fences...
 
One (possible) way to build them is with standard field fence, 6" x 6" 'woven' wire, that is mounted to a piece of PVC pipe (cheap black plastic works) sliped over a steel fence post as an insulator.
 
Remember that electric fences need good 'grounding' to work properly.  Dry ground may require a bit of help with a grounding grid on the  outside of the electrified fence.  That can be another piece of field fence that is layed flat and pinned to the ground with some simple U shaped pieces of wire.
 
Keep the electrified wires clear of the ground and grass, weeds, etc., get as good a charger as you can, and good luck.
 
Dennis Morefield
Talent, OR, USA
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Dennis Morefield
Sideline Beekeeper, Oregon, USA
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