Spotlight on Yellow Dock: Soothing, Anti-Inflammatory, and Cleansing

Now that the fall colours have passed their peak and most of the leaves have fallen, things are going to look a little barren until everything starts growing again in April. This is a time of rest for the plant people. But it is not yet a time of rest for herbalists. Harvesting season starts in April, peaks in June and July and then slows down a fair bit until it peaks again from late October until the end of November.

This is the time when we harvest most of our roots and rhizomes. Although they look somewhat like roots and grow under the ground (or occasionally along the surface), rhizomes are not actually roots. They are underground stems that allow a plant to spread out laterally along the surface of the ground. Nevertheless they are harvested the same as roots. When we harvest the roots and rhizomes of herbs it’s important that it is done after most or all of the aerial parts of the plant have died back. This is when they are at their greatest potency. At this time the life force of the plant has withdrawn into the roots and rhizomes. This is also when they are full of important chemical constituents that the plant has stored to help it survive through the winter.

In my practice I try to limit the number of root herbs that I harvest because harvesting roots usually necessitates killing the plant. As a result, I tend to minimize my use of root herbs if I have several alternative species that can be substituted in formulations. This isn’t always possible and it is fortunate that there are many plant species that like the kinds of changes that we humans make to our environment. Most of these plants are alien species that have naturalized in North America. They tend to be common wherever people are common and it is very difficult to overharvest them.

One herb that falls into this category is yellow dock. The common name “yellow dock” has been used to refer to three different medicinal plants that are used interchangeably. In medicinal herb books it primarily refers to curly dock (Rumex crispus), but it sometimes refers to bitter or broad-leaved dock (R. obtusifolius) and acute dock (R. x acutus). The latter was once thought to be a distinct species but is now recognized as a hybrid between the first two species that sometimes occurs where their ranges overlap. These species are all called yellow dock because of the yellowish colour of their roots. Traditionally they were believed to have almost identical therapeutic actions, which is not surprising for plants that are so closely related that they can readily hybridize. However, curly dock is usually used more by herbalists.

The Rumex species are members of the Smartweed family. This family includes a number of other medicinal plants such as sheep sorrel (Rumex acetosella) and Chinese rhubarb (Rheum officinale and R. palmatum), as well as edible species such as garden sorrel (Rumex acetosa), garden rhubarb (Rheum rhaponticum) and buckwheat (Fagopyrum esculentum).

YELLOW DOCK HABITAT AND HARVESTING

Curly dock grows in a wide variety of habitats, from open fields to transition areas where it gets direct sunlight only part of the day. Although it prefers slightly moist soils, it can tolerate dry rocky or sandy soils as well. In drier conditions it tends to produce seed and die back earlier in the year, in August or September depending on how dry it is. In hot, dry summers it is best to harvest this herb in areas where it receives direct sunlight only part of the day as the soil conditions in these areas will be more moist. In cool, wet summers it is best to harvest curly dock in open areas with good drainage. Curly dock is primarily distinguished by its leaves which have elongated blades with curly margins from which it gets its name. In Ontario it is the most common species.

In contrast, broad-leaved dock thrives in a much narrower range of conditions. It only grows in relatively moist soils and doesn’t like too much sun. It is most common in open woodlands and transition areas near streams, bogs and other sources of water. The leaves of this species have shorter, wider blades that are heart-shaped at the base. It is less common than curly dock.

Acute dock primarily occurs in transition areas where the ranges of the other two species’ overlap. Its leaves are intermediate in appearance between those of the other two. Acute dock is not very common in Ontario.

All three of these species produce branching taproots that grow about two to three feet deep and tend to spread laterally to a radius of about eight to twelve inches. The root will tend to be larger in sandy soils and smaller in clay soils. The roots should be harvested after the flowering stalk and most of the larger basal leaves have died back. That can be as early as September when the conditions are dry, but is more typically late October to the end of November as with most root herbs which leave a dried stalk that is easy to recognize after the aerial parts of the plant die back. It is the roots of the three to four year old plants that are preferred. Plants this age tend to produce two to three flowering stalks, whereas two year old plants produce one, and older plants usually produce more than three in any given year.

YELLOW DOCK TINCTURES AND INFUSIONS

A tincture can be prepared from the fresh or dried root of yellow dock, or it can be used as a decoction. Decoctions are necessary when using the harder, denser parts of herbs (i.e. roots, rhizomes and barks). To make a decoction, add 1-2 teaspoons of the chopped, dried root to 350 ml (1.5 cups) of room temperature water in a pot with the lid on and slowly bring it to a boil setting the element or gas burner at medium heat. As soon as it comes to a boil, turn the heat right down so that it is only slightly simmering. Simmer the root for 5 minutes, then turn off the heat and let it steep for another 15-20 minutes. Strain it and drink it. This is one dose.

Although the method for making a decoction that I have given above minimizes the use of heat, I prefer not to use decoctions because the continuous application of heat to herbs results in the break-down of some of their active constituents. Instead, I prefer to grind the herb to a coarse powder and prepare it as an infusion. Simply grind 1-2 teaspoons of chopped root and add it to a cup of freshly boiled water. Place some kind of cover on the cup and allow it to steep for 15-20 minutes, then strain and drink it.

It’s important that we use herbs that are stored in the “cut and sifted” form (in small chunks) and grind the plant material in unit dose amounts each time we use it because storing the herb as a powder promotes greater oxidation of its active constituents, which also reduces the potency of the herb. Since 1-2 teaspoons of root is too small an amount to easily grind with a small spice or coffee grinder, it is best to grind it with a mortar and pestle.

Although yellow dock root tea is quite effective, the tincture is the most effective way to use it, especially when prepared from the fresh root. The unit dosage depends on the strength of the tincture. I usually prepare 1:5 fresh root tinctures, which means that there is the equivalent of one gram of the fresh root in every 5 ml of tincture. At this strength the typical adult dose is 2.5-5 ml or 0.5-1 teaspoon.

As with most herbs, the typical dose for yellow dock is 3-4 times per day taken on an empty stomach. The best times are 15-20 minutes before meals and 30-60 minutes before bed. When using the tincture, add it to 25-30 ml (one ounce) of water and hold it in your mouth for 20-30 seconds before swallowing.

YELLOW DOCK MEDICINE

Yellow dock is most often used for its ability to facilitate detoxification. It aids with the removal of toxins from the tissues by supporting lymphatic and blood circulation, and ultimately with their removal from the body by supporting liver, colon and kidney function. As a result, yellow dock is an excellent herb for treatment of all chronic inflammatory conditions that are at least partially related to tissue toxicity. These include acne, boils, eczema, psoriasis, seborrhea, rheumatoid arthritis, other forms of rheumatism, gout and fibromyalgia. In treatment of toxicity-related conditions it combines well with burdock root or herb (Arctium spp.), cleavers herb (Galium aparine), yellow bedstraw herb (Galium verum), elecampane root (Inula helenium), sweet clover herb (Melilotus spp.), dandelion root, leaf or flower (Taraxacum officinale), red clover flower (Trifolium pratense), stinging nettle herb or rhizome (Urtica dioica) and blue violet herb (Viola spp.).

Yellow dock is also very effective for treatment of chronic constipation and to help support specific channels of elimination. It helps with poor lymphatic drainage, swollen lymph nodes, inflammation of the spleen, liver and gallbladder congestion, and for treatment of inflammatory conditions of the urinary tract, especially when they are due to high levels of toxicity in the urine.

Yellow dock helps to improve digestion. It will also improve appetite for people who are convalescing and with anorexia. It helps to reduce inflammation in the digestive tract such as in gastritis, colitis and irritable bowel syndrome, and will reduce diarrhea as well.

Although yellow dock has a mild influence on the respiratory system and some ability to reduce fever, it is rarely used in the treatment of acute respiratory infections except for the treatment of swollen lymphatic tissues such as in tonsillitis. It is also effective for treatment of mouth ulcers.

Yellow dock has a history of being use to treat fibrocystic breasts and uterine fibroids. It can also be effective for the treatment of tumours. However, it has a more supportive role in the treatment of cancer. It is not one of the more potent anticancer herbs.

GUIDELINES AND CAUTIONS

Although yellow dock root is relatively non-toxic, its use does have a couple of minor limitations. Firstly, it is a moderately astringent and should not be combined with other moderately to strongly astringent herbs. Secondly, yellow dock contains oxalates. These constituents are mildly irritating to the urinary tract with long-term use and, if other predisposing factors are present, could contribute to development of urinary stones. As a result, this herb is best combined with other herbs at a proportion of 20-25% of the formulation.

Although some authors recommend using yellow dock root in pregnancy because it’s a good source of iron, it’s best not to use this herb in pregnancy or while nursing because these are not good times to be detoxifying. Yellow dock is also not recommended for anyone with a history of kidney stones or where there is any kind of bowel obstruction.

Yellow dock is a great example of an herb that has a symbiotic relationship with humans. At this time, many wild North American herbs are becoming rare or endangered due to habitat destruction, competition with alien species, imported diseases or pests, and sometimes by over-harvesting for medicinal purposes. Fortunately, there are many excellent herbs such as yellow dock that are readily available and very adaptable. These herbs allow us to rely less on more sensitive native species of plants. Many of them are also easy to find and recognize and are perfect herbs for beginners and more casual herb enthusiasts to work with and learn from. November is our last opportunity to do this. If you’re looking for a great excuse to get out into Nature this month and learn about or even harvest some herbs, yellow dock is an excellent choice. Enjoy!