B. nigra may refer to:

• Ballota nigra, a perennial herb of the family Lamiaceae
• Betula nigra, a species of birch native to the eastern United States from New Hampshire west to southern Minnesota, and south to northern Florida and east Texas
• Brassica nigra, the black mustard, an annual weedy plant cultivated for its seeds, which are commonly used as a spice

See also

• Nigra (disambiguation)

Topics referred to by the same term

This disambiguation page lists articles associated with the same abbreviated species scientific name.
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