drift fence
A fence built in open rangeland not to enclose an area but to direct the movement of livestock, channeling them toward water, corrals, or a specific part of the range. Drift fences work with the animals' natural tendency to drift with the wind or toward water — they don't confine, they guide. Remnants of old drift fences mark the desert and grassland landscape of the West, their posts weathered to silver.
Etymology
English compound — a fence that manages the drift of cattle. "Drift" here from the Old English drīfan, to drive.
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