We will not consider all subspecies, but basically, it is a large tree, which tends to reach 1.5 m in diameter. On old trees, the bark is thick, with deep folds, dark gray in color. Crown wide, round or oval. Young shoots are bare, hairy at the tips. Leaves lanceolate or narrowly lanceolate with pointed ends, finely lobed. Spikes up to 5 cm long, which open in April-May, at the same time as the leaves or a little later. White willow has a well-developed and plastic root system. White willow does not have a central root, so the lateral roots are better developed and form the base of the tree. The roots reach a depth of 2.5-3m, the wetter the soil, the less the root system develops.
It is good to know that white willow, together with other willow species, often forms various hybrid species, which are often difficult to distinguish from the basic species.
The following species are used for medicinal and pharmaceutical purposes in different countries: Salix acutifolia Willd., Salix babilonica L., Salix aurita L., Salix caprea L., Salix fragilis L., Salix cinerea L., Salix elegantissima Koch., Salix viminalis L., Salix purpurea L., Salix triandra L..
For medicinal purposes, the bark of the white willow is used, which is collected from two-three-year-old shoots, in the spring, during the juice extraction, because it is during this period that it is easiest to separate the bark from the wood. For collection, cut or pick the shoots, which are then peeled. The bark is dried in shaded places on sieves or hung on a string. If necessary, drying can also be done in forced dryers not exceeding 50C. The drug is ready when it remains hard and brittle.
The inside of the rind should be smooth with no wood remains, a soft straw, light pink or light brown shade. The drug has no smell. Bitter or astringent in taste.
White willow bark is also recognized as an official medicinal plant. The drug is stored in closed paper bags, in well-ventilated rooms, preferably for no longer than 2 years, although theoretically it does not lose its effectiveness for up to 4 years.
White willow bark is rich in various biologically active compounds, the most important of which are phenolic glycosides, salicylic acid derivatives and flavonoids.
Glycosides of salicylic acid have been found in the barks of various species of willows, including salicin, a glycoside that breaks down as a result of enzymatic hydrolysis into saligenol alcohol, which is further hydrolyzed into salicylic aldehyde and salicylic acid. Therefore, willow bark contains salicylic acid in its pure form. Apart from salicylic acid itself, other salicylic acid glycosides such as salidroside, salicoside, salireposide, fragalin, salicortin, triandrin, vimaline, tremuloidin and other compounds are also found in the willow bark and leaves.
White willow bark contains not only salicylic acid glycosides, but up to 5% flavonoids are also found in the bark and leaves, among which anthocyanins and their glycosides - purpurinidin, cyanidin 3-glucoside, delphinidin 3-glucoside, catechins (+)-catechin, epicatechins, gallocatechins , apigenin flavonoids 7-0-(4-0-n-coumaroyl-glycoside), salipurposide, isosalipurposide, salidroside, narcisin.
Willows of various species also have a considerable amount of tannins in their bark. There are no tannins in willow wood, they are basically only in the bark and leaves, according to various information sources, their amount is on average 2-8%. White willow and gray willow have the highest tannin content, up to 20%.
Medicinal significance
Willow bark preparations have the following medicinal properties: anti-rheumatism, antiseptic, disinfecting, astringent, diaphoretic, antipyretic, diuretic and bile-repelling, hypotensive. In addition, willow bark preparations are able to increase the secretion of bronchial glands and digestive glands, resulting in increased secretion of mucus, gastric and pancreatic juices.
It has also been experimentally determined that water-alcohol extracts and solutions of willow bark work as an anti-inflammatory, temperature-reducing and pain-relieving agent. Bark extract enhances blood clotting. It is important to know that other parts of the plant have completely different effects. Alcohol and water extracts also have strong antiviral properties.
Salicin glycoside, which is relatively abundant in willow bark, when it enters the body, is split into saligenol alcohol and glucose under the influence of enzymes. Saligenol is an unstable compound, so it gradually hydrolyzes, initially to salicylic aldehyde and later to salicylic acid, which is also the main substance responsible for the healing properties of willow.
It is the salicylic glycoside that has a temperature-reducing effect, increasing the release of heat from the body. Under the influence of salicin, the blood vessels under the skin expand and sweat increases, moreover, the effect of salicin is weaker than that of salicylic acid.
Pharmacological studies have shown that the biologically active substances of willow bark, specifically salicylic acid glycoside, dilate coronary vessels and increase the amplitude of heart contraction, slightly reducing the heart rate.
Alcohol and water extracts from the bark have antiviral effects. The phenolic salicin glycoside, which is up to 7% in the bark, is the main element that provides the healing effect of willow bark, it has antifebrile, diuretic, analgesic and diaphoretic properties. Thanks to salicylates, the release of uric acid increases, so willow can also be used in gout.
Galenic preparations from willow bark and leaves are used in clinical settings. Most often, they are used to reduce the temperature and create a pain-relieving effect in case of colds and rheumatism.
Bark decoctions are also used in case of aggravated respiratory diseases to reduce inflammations of various etiologies.
As an astringent and anti-inflammatory agent, use willow bark in case of stomatitis, gingivitis and upper respiratory tract catarrh. Willow bark is often found in bile, urine, and sweat-repellant mixtures. In clinical medicine, willow bark is also used to stop bleeding.
Willow bark contains compounds of catechin tannins, which have an antispasmodic and choleretic effect, so the bark can be used for the treatment of various stone diseases.
Due to its high content of tannins, willow bark is used to stop bleeding of various origins, to rinse diarrhea and female genital organs, in case of various inflammations. A decoction of willow bark is used for conjunctivitis and blepharitis to rinse the eyes.
A decoction of willow bark is used to rinse the throat and mouth, in case of gingivitis and angina. These properties are due to the astringent effect of tanning agents.
Vītola mizu lieto arī ārīgi, vannās, kāju vannās, lai
mazinātu to svīšanu, kā arī lai ārstētu ādas slimības. Mizas pulveri izmanto
aplikāciju veidā, vai sajaucot to ar neliela daudzuma ūdeni, liek uz pūžņojošām
brūcēm.