When trying keep bears out of bee yard. You must have serious fence charger. Really good grounding. Bottom hot wire has be almost touching soil. Keep grass weeds etc clear. I ended up adding 4 more runs of hot wires and moving wires down as you can see bear was going under wire. Also was told put aluminum foil with peanutbutter on hot wire so bear touches get shocked. Kinda crazy idea but bet it works. Bears very sneaky and destructive. Much worse nuisance than pigs. Also dont have bee yard under or around tree. Beer will climb tree and drop into bee yard. Then destroy everything. Knock bee hives onto hot wires shorting out. One bee yard i fastened metal fence on ground around yard and bonded ground to fencing on ground also. This way there standing on metal when touch hot wire. Resolved issues. No digging etc.