If deer are getting into your garden, and you don't want to make a eight-foot-tall fence, you'll find you can keep them out with a much lower fence as long as the fenced area is narrow. If the area you enclose is only six feet wide, the deer will not jump over even a five- foot fence, because they would feel claustrophobic inside. They need a little room to get a running start even for small jumps and so won't enter small areas. If your area is wider than six feet, you can put a second line of short fence inside the outer fence to discourage the deer. - from the Easier, Faster, Better section of
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