CURLED DOCK or YELLOW DOCK
Rumex crispus

Location
Beyond the helicopter pad south of the Research Building, near the athletic field, and along the path into the woods.

Description
The curled dock has lance-shaped, pointed, lower leaves that are with strongly curled borders.  The three flat wings of the fruit are heart-shaped and are entire, and may be faintly toothed.  The distinctly stalked flowers grow in whorls forming several branched racemes (Newcomb 1997).

History
The Swedish and English settlers used the leaves as greens and are cooked like spinach (Erichsen-Brown 1979). American Indians cooked the seeds in gruel (Duke 1990).

The Cheyenne used an infusion of powdered root for hemorrhage of the lungs and moistened powdered root as a poultice for wounds and sores. The Chippewa used the root for itching and skin problems (Erichsen-Brown 1979).

Historically, the root was used as a cathartic, diuretic, as a treatment for dyspepsia, syphilis, leprosy, cancers, other tumors, and as a dentifrice (Erichsen-Brown 1979). The root has also been used for rheumatism (Grieve 1998, Foster 1990), hemorrhoids, scurvy, chronic enlarged lymph glands, liver ailments, and sore throats (Foster 1990).  It has been used in diphtheria (Grieve 1998) inflammation of the respiratory tract, and for treating sexually transmitted diseases.  It has been used to cause or relieve diarrhea; the effect appears to  depend on dose and  harvest time, which may affect the concentrations of anthraquinones and tannins (Foster 1990). Asian Indians use root preparations to treate toothache, gingivitis and as a tooth powder.  Brazilians have applied the root decoction externally for swollen lymph nodes and internally for fevers or as a tonic.  Chinese have used Rumex as a laxative (Duke 1990).

The seeds were once used for dysentery (Erichsen-Brown 1979).

The leaves were poulticed for ulcers, sore eyes, swellings, itching, and to relieve stinging nettle stings (Erichsen-Brown 1979).

Current Medicinal Uses
Yellow dock root is available in herb teas and preparations in the U.S.; it is used to treat anemia, constipation and other conditions. Yellow dock contains anthraquinones, oxalates, tannins (5%), and vitamin C 30 mg/100g. (Duke 2001). Young leaves are cooked and eaten by various ethnic groups. The use of yellow dock should be avoided because its oxalate content is so high (see Adverse Effects).

Adverse Effects
Serious oxalate poisonings have been reported in sheep and other livestock (Panciera 1990). In humans, overdose usually results in nausea, diarrhea, and polyuria (Foster 1999), but one fatal human poisoning has been reported (Reig 1990).

References
Duke JA. Handbook of Medicinal Herbs. CRC Press, Boca Raton, 2001. (p. 414)

Erichsen-Brown C. Medicinal and Other Uses of North American Plants: A Historical Survey with Special Reference to the Eastern Indian Tribes. Dover Publications, Inc., New York, 1979 (pp. 223-224)

Foster S, Duke JA. Eastern/Central Medicinal Plants. Houghton Mifflin Company, Boston, 1990. (p. 214)

Foster S, Tyler VE. Tyler's Honest Herbal, 4th Ed. Haworth Herbal Press New York, 1999:391-392.

Grieve M. A Modern Herbal. Tiger Books International, London, 1998 (first published in 1931 by Jonathan Cape Ltd):259.

Newcomb L. Newcomb’s Wildflower Guide. Little, Brown and Company, Boston, 1977. (p. 404)

Panciera RJ, Martin T, Burrows GE, Taylor DS, Rice LE.  Acute oxalate poisoning attributable to ingestion of curly dock (Rumex crispus) in sheep. J Am Vet Med Assoc. 1990 Jun 15;196(12):1981-4.

Reig R, Sanz P, Blanche C, Fontarnau R, Dominguez A, Corbella J.  Fatal poisoning by Rumex crispus (curled dock): pathological findings and application of scanning electron microscopy. Vet Hum Toxicol. 1990 Oct;32(5):468-70.