Nature's Pharmacy: Ancient Knowledge, Modern Medicine

Salix alba
Willow

Despite the 300 species and hybrids of Salix alba, the appearance of the tree offers little variety. Salix alba is a deciduous tree that grows from 75-100 feet tall and 50 feet in width. Its branches are flexible and bend toward the ground, giving the tree its nickname "weeping." The branches are golden yellow to dark brown in color. The dark green leaves have a shiny look with a white underside. Each leaf is serrate with 7-10 glandular teeth that come to a single point at the end of the leaf. The leaves are 4-10 cm long and 1-2.5 cm wide.

Salix bark has a glossy outer surface with older bark being rugged and younger bark being smooth or slightly wrinkled. The bark appears as a brown-gray to greenish color on the tree. The bark's underside differs with its yellow-red or brown surface. It contains up to 13 percent tannin as its primary constituent. It also possesses 2.5-11 percent salicin.

Salix reproduce with spiked catkins-seeds attached to a fluffy white substance. The seeds are released into the air when ripe. Female catkins grow on leafy branchlets with a yellowish-green color. Salix trees flower in May and fruit in early June.

Salix alba flourishes in wet areas, absorbing and transpiring immense amounts of water. Most Salix trees grow in the northern hemisphere, usually along rivers and streams in the United States, and in North Africa, central Asia and Europe.

History
The bark of Salix alba has been used to relieve pain and reduce fever for over 2,000 years. In the 5th century B.C.E., Hippocrates, a Greek physician, prescribed it for the pain occurring in childbirth. Biblical scriptures reflect the use of willow bark as a "tea," which had an aspirin effect.

In mid-18th century England, the Reverend Edmund Stone tasted white willow bark and found its bitterness similar to that of cinchona bark, the source of quinine. He wrote of the "success of the bark of the willow in the cure of the agues (fever)." Reverend Stone had reached this conclusion based on the willow's growing in damp areas. He reasoned that agues abound in damp areas and therefore the willow bark possessed properties appropriate to curing feverish conditions.

Salicin, the active ingredient in willow bark, was discovered in 1827. In conjunction with Reverend Stone's theories, it was first used in 1875 to treat rheumatic fever. Later uses included the relief of joint inflammation and reduction of uric acid in the blood of patients with gout. In the 1890s, the Bayer company used Salix bark in the development of aspirin. Aspirin, containing salicin, was introduced in 1899. The bark's salicin content made it useful for such conditions as pain and fever. Around 1987, physicians began to prescribe aspirin to prevent clotting in the coronary arteries.

Gathering and Preparation
Salix bark is stripped from the tree in spring when it is moist with sap. The bark is then prepared in a variety of ways. Salix as a liquid extract can be prepared by soaking one teaspoon of bark in cold water for 8-10 hours. The bark is strained and removed from the water. One cup of this extract equals a low dose of aspirin (about 60-150 milligrams.) Liquid extracts can also be prepared with alcohol and taken at a dosage of 1-3 milliliters. These extracts are generally used for cold symptoms, but can be used simply as teas. When consumed as a tea, sugar or honey is added to sweeten the bitter flavor of the bark. Preparations for decoctions include soaking or boiling 1-3 teaspoons bark in 1 cup of cold water for 2-5 hours. The liquid is bitter and taken unsweetened. The dosage is 1 cup per day, a mouthful at a time. Although the bark is the most commonly used part of the salix tree, its leaves can also be eaten. This produces results similar to the bark as the leaves contain a concentration of salicin.

Warnings

• May cause upset stomach, nausea and vomiting
• Avoid if you are pregnant or breast feeding.
• Consult a physician before using salix bark to prevent heart attack or stroke.
• Avoid if you have an ulcer.
• Avoid if you have asthma or tinnitus (ringing in the ears)
• Avoid if you are allergic to aspirin.
• Do not give willow bark to children as it may cause Reye's syndrome. Although rare, the syndrome is potentially fatal and damages a child's brain and liver.

Current Medicinal Uses
Due to its versatility, salix alba can be used to ease a variety of medical problems. It is used to decrease the discomfort of cold and flu symptoms. Salix also reduces fevers that accompany these conditions. It can also be used as a gargle.

Salix is used to ease inflammation and pain caused by carpal tunnel syndrome, arthritis or rheumatism. Since no gastric or intestinal upset is associated with the use of Salix, it is sometimes prescribed instead of aspirin. Salix bark may also have the same blood-thinning effect as aspirin, although there is no evidence to prove this theory.

Salix bark can be used to aid digestive disorders. It has been used to ease such conditions as indigestion, chronic diarrhea and dysentery. External uses include deodorizing washes for sweaty feet, washes for sores, burns, or wounds, and as a skin moisturizer.