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Polygonum persicaria - spotted ladysthumb

Scientific Family
Polygonaceae
Synonyms
Persicaria maculata, Persicaria maculosa
Other common names
pale smartweed
spotted knotweed
Plant type
Forbs and Subshrubs
Origin
Introduced
Lifecycle
Annual or perennial
Similar species
Polygonum lapathifolium
Height
1 to 3 feet
Riparian
Yes

Erect or spreading stems which may initiate roots at their lower nodes.

Lower stem internodes not inflated. Inflorescence dense, perianth (sepals and petals) pink, not glandular-pitted. Leaf node sheaths with marginal bristles. Propagates by rhizomes or stolons.

Habitat

Wet places, mostly along water courses.

Plant Community
Riparian
Low elevation
3300
High elevation
7200

Flower Characteristics

Pink to rose colored flowers are borne on dense spikes. The petals are fused into a bell-shaped tube.

Flower color
Pink
Flower shape
Bell-shaped
Tubular
Yes
First bloom month
July
Last bloom month
September
Flower clusters
Elongated

Leaf and Stem Characteristics

Leaves may have a classic pink to purple "lady's thumb" print near the middle. Leaf nodes are conspicuous and sheathed.

Leaf type
Simple
Leaf color
Green
Leaf shape
Narrow
Leaf margin
Smooth
Leaf attachment
Alternate
Leaves clasp
No
Leaf hairs
Leaves
Spines
No

Fruit and Seed Characteristics

Fruit type
Achene
Fruit color
Brown

Flattened and shiny.