Water-hemp or waterhemp is a common name for several plants and may refer:
In the genus ''
Amaranthus'':
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Amaranthus australis
''Amaranthus australis'' is also known as southern amaranth or southern water-hemp. The plant usually grows from in height, though some have been known to grow up to high. The stems can be up to 30 cm in diameter. It is a herbaceous annual ...
'' - southern water-hemp
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Amaranthus cannabinus'' - salt-marsh water-hemp,
tidal marsh water-hemp or water-hemp pigweed
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Amaranthus floridanus'' - Florida water-hemp
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Amaranthus tuberculatus'' - rough-fruit water-hemp or tall water-hemp
In other genera:
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Ayapana triplinervis''
{{Plant common name