Legal Insight. Business Instinct.


The grass was greener on the other side. Or at least my cows thought so. They jumped the fence, or went under the fence, or perhaps through the fence, and joined my neighbor’s herd. I called my neighbor and told her that it would not hurt my feelings if she fed my cows all winter long. My neighbor laughed, but only briefly and politely. I then promised her that I would fix some fence.

Idaho law dictates what constitutes a legal fence. Idaho Code § 35-102 states that a lawful fence may be any of the following:

Stone Fence: Must be four feet high and two feet at the base and one foot thick on top.

Worm Fence: Must be four feet high and the rails must be well laid.

Post & Rail: The posts must be well laid and not more than eight feet apart. There must be at least three six-inch boards, or rails not less than 2 1/2 inches in diameter. The top board or rail must not be less than four feet from the ground. If rails not less than three inches in diameter are used, the posts may be set 12 feet apart.

Wire Fence: Probably most common, a wire fence must have posts set not more than 24 feet apart with three stays placed at equal distances between the posts. All wires must be securely fastened to the post with not less than three strands of barbed wire. The bottom wire must not be more than 21 inches from the ground and the other wires a proper distance apart. The fence must be at least 47 inches high.

Other: If made in whole or in part of brush, ditch, pickets, hedge, or any other materials, the fence must be equal in strength and capacity to turn stock as the fences described above.

One purpose of these legal fence requirements is to “fence out” cattle and other livestock in an open range. However, in a herd district, these same fence requirements dictate the requisite legal fences that must be built to contain livestock. If you live in a herd district, and if your cows escape through your fence, and your fence is not a legal fence, you may be “per se” negligent and responsible for any damages that may result.

Remember that good fences make for good neighbors, and a legal fence will keep you and your cows on the right side of the law.

– Lance J. Schuster is a lawyer at Beard St. Clair Gaffney. He and his wife raise kids and cattle on their small farm near Idaho Falls. He can be reached at 523-5171 or

Skip to content