American water-willow
Family
AcanthaceaeScientific Name
Justicia americanaOther Common Names:
water-willow
Synonyms (former Scientific Names):
Justicia umbratilis
Dianthera americana
Dianthera americana var. subcoriacea
Justicia americana var. subcoriacea
Justicia mortuifluminis
Leaves
Arranged oppositely along the stem and are elliptic to linear in outline, approximately 6 inches long. Leaves have a distinctive white midvein that runs the length of the entire leaf.
Identifying Characteristics
The linear leaves with a white midrib, the prominent white lines along the stems, and the colonizing growth habit along shorelines are all characteristics that help to distinguish water willow from most other shoreline plants.
Flower Seed Head
Arranged oppositely on crowded spikes at the ends of long flower stalks (peduncles) that originate from the position between the leaf and the stem (leaf axils). Petals are white with purple tinges. Flowers have a distinctive lower lip that is approximately 3/4 inch long.
Seed Fruit
Stems: May reach 2 1/2 feet in height and are stout with prominent white lines.
Fruit: A capsule that is approximately 1/2 inch long
Where Found
A perennial from rhizomes that is capable of forming large colonies. Water willow is primarily found along the shorelines or in shallow water of lakes, ponds, or streams.
Life Cycle
perennial
Plant Type
Herb