http://www.fairfaxcounty.gov/code/animals/#
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“Domestic Fowl
Fowl, such as chickens, ducks, turkeys, and geese, may only be kept on lots that are two acres or greater. They shall not exceed the ratio of one bird unit per one acre, with a bird unit defined as:
32 chickens = 1 bird unit
16 ducks = 1 bird unit
8 turkeys = 1 bird unit
8 geese = 1 bird unit
Only fowl six months or older are counted in the ratio"
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