Burke: Rumex obtusifolius

	Rumex obtusifolius
	bitter dock
Habit	Robust perennial from a large root, without rhizomes, the single stem unbranched below the inflorescence, 6-12 dm. tall.
Leaves	Basal leaves with sheathing stipules and long petioles, the blade broadly oblong or ovate-oblong, cordate at the base, 10-20 cm. long; cauline leaves several, reduced upward.
Flowers	Inflorescence a large panicle, the branches ascending, leafy to mid-length; flowers numerous, borne in verticils, the lower whorls several times as far apart as the upper; pedicels slender, recurved, longer than the perianth, jointed below mid-length; flowers perfect, greenish-brown; outer 3 perianth segments 3 mm. long; inner 3 segments ascending, ovate, 5 mm. long, strongly veined, with 2-4 teeth on each margin, usually one segment with a prominent lump on the base; styles 3.
Fruits	Achene 2 mm. long, smooth.

	Rumex obtusifolius
Flowering time	March-September
Habitat	Moist roadsides and wasteland.
Distribution	Occurring on both sides of the Cascades in Washington; widely distributed throughout much of North America. [WildflowerSearch map] [BONAP county map]
Origin	Introduced
Conservation status	Not of concern
Sibling taxa	R. acetosa, R. acetosella, R. conglomeratus, R. crispus, R. dentatus, R. maritimus, R. occidentalis, R. patientia, R. paucifolius, R. persicarioides, R. salicifolius, R. sanguineus, R. stenophyllus, R. venosus
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

Rumex obtusifolius

bitter dock

Habit

Robust perennial from a large root, without rhizomes, the single stem unbranched below the inflorescence, 6-12 dm. tall.

Leaves

Basal leaves with sheathing stipules and long petioles, the blade broadly oblong or ovate-oblong, cordate at the base, 10-20 cm. long;

cauline leaves several, reduced upward.

Flowers

Inflorescence a large panicle, the branches ascending, leafy to mid-length;

flowers numerous, borne in verticils, the lower whorls several times as far apart as the upper;

pedicels slender, recurved, longer than the perianth, jointed below mid-length;

flowers perfect, greenish-brown; outer 3 perianth segments 3 mm. long; inner 3 segments ascending, ovate, 5 mm. long, strongly veined, with 2-4 teeth on each margin, usually one segment with a prominent lump on the base;

styles 3.

Fruits

Achene 2 mm. long, smooth.