Burke: Persicaria hydropiperoides vs. Persicaria maculosa

	Persicaria hydropiperoides	Persicaria maculosa
	water pepper, swamp smartweed	heartweed, lady's-thumb, spotted lady's-thumb, redshank
Habit	Herbaceous perennial, up to 1 m. tall, usually decumbent and tending to root freely.	Usually a glabrous annual, simple to branched, erect to spreading, up to 1 m. tall.
Leaves	Leaves numerous on short petioles, alternate, scarcely reduced upward, lanceolate to oblong-lanceolate with an acute base, 5-12 cm. long; sheathing stipules 1-2 cm. long with bristly hairs around the top.	Leaf blades elliptic-lanceolate to narrowly oblong-lanceolate, 5-10 cm. long, usually with a purplish triangular or lunar spot about mid-length, narrowed to a short, thick, non-jointed petiole; stipules obliquely cylindric-conic, never lacerate, bristly along the nerves.
Flowers	Inflorescence of 2 or more spike-like, interrupted racemes; perianth greenish to white or pinkish, 2.5-3 mm. long, 5-lobed half the length, the segments oblong and sub-equal; stamens 8 with short filaments	Inflorescence of crowded, pedunculate, compound racemes; flowers white, usually strongly pinkish-tinged; perianth 1.5-2 mm. long, 5-parted.
Fruits	Achene with three sharp angles, black, smooth and shining, about 3 mm. long.

	Persicaria hydropiperoides	Persicaria maculosa
Identification notes		Achene lenticular, 2-2.5 mm. long, ovate-rotund in outline, black, smooth and shining.
Flowering time	July-September	March-September
Habitat	Moist to swampy areas, often growing in mud, from the lowlands to the lower mountain valleys.	A weedy species, usually on moist, cultivated or otherwise disturbed soil.
Distribution	Occurring chiefly west of the Cascades crest in Washington; British Columbia to Mexico and South America, east across North America to the Atlantic coast. [WildflowerSearch map] [BONAP county map]	Occurring on both sides of the Cascades crest in Washington; Alaska to California, east across North America to the Atlantic Coast. [WildflowerSearch map] [BONAP county map]
Origin	Native	Introduced from Eurasia
Conservation status	Not of concern	Not of concern
Sibling taxa	P. amphibia, P. hydropiper, P. lapathifolia, P. maculosa, P. punctata, P. wallichii	P. amphibia, P. hydropiper, P. hydropiperoides, P. lapathifolia, P. punctata, P. wallichii
Web links	Local floras: BC, CA, OR, WA Local Web sites: CalFlora, CalPhotos, Flora NW, PNW Herbaria WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search	Local floras: BC, CA, OR, WA Local Web sites: CalFlora, CalPhotos, Flora NW, PNW Herbaria WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search

Persicaria maculosa

water pepper, swamp smartweed

heartweed, lady's-thumb, spotted lady's-thumb, redshank

Habit

Herbaceous perennial, up to 1 m. tall, usually decumbent and tending to root freely.

Usually a glabrous annual, simple to branched, erect to spreading, up to 1 m. tall.

Leaves

Leaves numerous on short petioles, alternate, scarcely reduced upward, lanceolate to oblong-lanceolate with an acute base, 5-12 cm. long; sheathing stipules 1-2 cm. long with bristly hairs around the top.

Leaf blades elliptic-lanceolate to narrowly oblong-lanceolate, 5-10 cm. long, usually with a purplish triangular or lunar spot about mid-length, narrowed to a short, thick, non-jointed petiole;

stipules obliquely cylindric-conic, never lacerate, bristly along the nerves.

Flowers

Inflorescence of 2 or more spike-like, interrupted racemes;

perianth greenish to white or pinkish, 2.5-3 mm. long, 5-lobed half the length, the segments oblong and sub-equal;

stamens 8 with short filaments

Inflorescence of crowded, pedunculate, compound racemes;

flowers white, usually strongly pinkish-tinged;

perianth 1.5-2 mm. long, 5-parted.

Fruits

Achene with three sharp angles, black, smooth and shining, about 3 mm. long.

Persicaria hydropiperoides

Persicaria maculosa

Identification notes

Achene lenticular, 2-2.5 mm. long, ovate-rotund in outline, black, smooth and shining.

Flowering time

July-September

March-September

Habitat

Moist to swampy areas, often growing in mud, from the lowlands to the lower mountain valleys.

A weedy species, usually on moist, cultivated or otherwise disturbed soil.

Distribution

Occurring chiefly west of the Cascades crest in Washington; British Columbia to Mexico and South America, east across North America to the Atlantic coast.

[WildflowerSearch map]

[BONAP county map]