Definition

1. Noun:
   • A shrub native to the eastern and southern coastal United States: This sense refers to a specific plant species, Clethra alnifolia, known for its attractive, fragrant clusters of white flowers.
   • A tree native to the western United States: This sense refers to a different plant species, Alnus rhombifolia, also commonly called the white alder, which is a tree rather than a shrub.

Usage Examples

• Noun:
  • The garden's border was planted with white alder for its summer blooms. (Refers to the shrub Clethra alnifolia.)
  • We sat in the shade of a large white alder by the riverbank. (Refers to the tree Alnus rhombifolia.)

Advanced Usage

• In botanical or horticultural contexts: The term is precise and refers to specific species. Context (geographic location or description as "shrub" vs. "tree") is essential for clarity.
  • The white alder (Clethra alnifolia) is prized for its tolerance of wet soils.
  • The white alder (Alnus rhombifolia) is a common riparian tree in California.

Variants and Related Words

• Sweet pepperbush: A common name for the shrub .
• Sierra alder: A name sometimes used for related alder trees in western North America.

Synonyms

• For the shrub (): summer-sweet, coastal sweet pepperbush.
• For the tree (): California alder, mountain alder (though this can refer to other species).

Notes on Meaning

This is a case of a single common name referring to two distinct botanical species: 1. The primary definition is the flowering shrub, Clethra alnifolia. 2. The secondary definition is the riparian tree, Alnus rhombifolia. The shared name "alder" is misleading, as they belong to different plant families.

Noun

1. shrub of eastern and southern coastal United States having beautiful racemes of spice-scented white flowers
2. tree of western United States