Used predicatively in phrase to lie shack, said of land so situated as to be liable to ‘shack’.
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the world > food and drink > farming > farm > farmland > grassland > produce grass [verb (intransitive)] > serve as pasture
graze1625
pasture1655
to lie shack1787
1787 W. MarshallProvincialisms in Rural Econ. Norfolk II. 387Shack, stock turned into the stubbles after harvest are said to be at shack. Grounds lying open to common fields are said to ‘lie quite shack’.