curly dock (Rumex crispus)
SCIENTIFIC SYNONYMS: There are no scientific synonyms for
CONFIRMATION STATUS: Pending confirmation.
TAXONOMY: The currently accepted scientific name for curly dock is
Rumex crispus L. Rumex crispus hybridizes with many other species of
Rumex ssp. Hybrids with Rumex obtusifolius (Rumex × pratensis Mertens
& Koch) are the most common in the genus, at least in Europe, and have
been reported for several localities in North America. Rumex crispus ×
Rumex patientia (Rumex × confusus Simonkai) was reported from New
Some eastern Asian plants differ from typical Rumex crispus in having
somewhat smaller inner tepals, longer pedicels, lax inflorescences with
remote whorls, and narrower leaves that are almost flat or indistinctly
undulate at the margins. These plants, originally described as Rumex
fauriei Rechinger f., are now treated as Rumex crispus subspecies fauriei
(Rechinger f.) Mosyakin & W. L. Wagner; the subspecies was recently
reported from Hawaii and may be expected as introduced in western
NATIVE STATUS: Introduced, United States and Canada.
GENERAL BOTANICAL CHARACTERISTICS:
Habit: This adventive perennial plant is 1–3' tall and little branched,
except where the flowers occur. Initially, it consists of a rosette of
basal leaves about 1' across. A flowering stalk bolts from this rosette
during the late spring. This stalk is round in cirumference, hairless,
Leaves: The alternate cauline leaves are up to 6" long and 1" across
(excluding their petioles). They are oblong- lanceolate, hairless, and
dull green. Their margins are crisped and undulate up and down.
Their petioles are up to 2" long, becoming broader at the base. The
basal leaves have a similar appearance, except that they are some-
what larger in size, their petioles are longer, and their margins are
less crisped or wavy.
Flowers: The inflorescence consists of a panicle of whorled racemes;
it is about ½–1½' long. Each plant has perfect (bisexual) and pistillate
(female) flowers; they are pollinated by the wind. Each yellowish or
reddish green flower is about 1/8" long and consists of 3 inner sepals,
3 outer sepals, 3 styles, and an ovary. Perfect flowers also have 6 sta-
mens. There are no petals. Each flower has a drooping pedicel about
¼" in length. There is no floral scent. Each flower matures into a dry
fruit about 1/6" long that contains a single seed. The inner sepals be-
come larger in size and membranous (at this stage, they are often call-
ed 'valves'). Each membranous sepal is cordate-oval in shape and only
slightly indented or well-rounded at the base. There is an elongated
tubercule that is about 1/3–1/2 the length of the sepal. The margin of
each sepal can be smooth or irregularly undulate, but it lacks conspic-
uous teeth of any kind.
Fruit/Seeds: The fruit and stems of curly dock become dark brown with
maturity. The rather large seeds are dark brown and 3-angled, tapering at
their tips. They are distributed to some extent by wind or water while ad-
hering to the membranous wings of the fruit.
Roots: The root system consists of a stout taproot that has a pale yellow
REGENERATION PROCESS: Curly dock propogates itself by reseed-
HABITAT TYPES: Habitats include seeps, glades, weedy meadows
(including areas prone to occasional flooding), pastures and fallow fields,
vacant lots, roadside banks and gravelly areas along railroads, edges of
yards and gardens, and miscellaneous waste areas. Disturbed areas are
preferred. Once established, curly dock can be difficult to eliminate.
SITE CHARACTERISTICS: Curly dock occurs at sites with full sun,
moist to dry conditions, and soil containing loam, clay-loam, or gravelly
material. It withstands drought, temporary flooding, and occasional mow-
ing. The seeds can persist in the ground for several decades (at least 50
years) and remain viable; this is one reason why curly dock, once estab-
lished in gardens or cultivated areas, can be difficult to eradicate.
SEASONAL DEVELOPMENT: The blooming period occurs during
the summer and lasts about a month.
GENERAL DISTRIBUTION: Curly dock is found in all states and
provinces in the United States and Canada. It reaches into nearly all
regions north to the Arctic Circle.
SKY MEADOWS DISTRIBUTION: To be determined.
IMPORTANCE AND USES: Few insects visit the flowers because they
are wind-pollinated. The foliage and other parts of Rumex spp. (Docks) are
eaten by the caterpillars of Lycaena spp. (Copper Butterflies) and various
species of moths. In particular, the caterpillars of Lycaena phlaeas ameri-
cana (American copper) occasionally feed on the foliage of curly dock,
although they prefer Rumex acetosella (sheep sorrel). Various upland
gamebirds and granivorous songbirds eat the seeds of Docks, particularly
during the winter. Meadow voles eat the foliage, while white-footed mice
eat the seeds. Other mammalian herbivores, however, tend to shun the
foliage of Docks because of its bitter taste and mild toxicity.
Curly dock has been used for a variety of folk and homeopathic remedies;
however, this is not recommended due to its toxicity.
Dock leaves are claimed to be an excellent source of both vitamin A
and protein, and are supposedly rich in iron and potassium. Because of
this, curly dock can be used as a wild leaf vegetable (particularly when
the plant is young); however, the toxic oxalic acid in the leaves should
be removed. Once the plant matures it becomes too bitter to consume.
If eaten, curly dock should only be consumed in moderation as it can
irritate the urinary tract and increase the risk of developing kidney stones.
Crooked Run Valley