Black poplar (Populus nigra L.) and trembling poplar (Populus tremula) are mainly used as medicinal plants. Both plant extracts are mainly used in the field of infectious diseases.
Occurrence and cultivation of poplar
Black poplar and trembling poplar are mainly used as medicinal plants. Both plant extracts are mainly used in the field of infectious diseases. Their wood is soft and easy to work, so it is often used in the field of furniture industry. Poplars grow dioecious with alternate, triangular and undivided small leaves. Often they are also heart-shaped to egg-shaped. The stipules drop off early. Most poplar species record same-sex catkins that droop limply without a perianth. The scales surrounding the flowers are shaped like roof tiles, and the bracts are toothed or slit. A typical feature of the family and genus are the seeds, which have a basal hairy tuft. Quaking aspen is also known as aspen or silver poplar. It has female and male catkins as flowers. The leaves move with even a very slight breeze, which is the origin of the saying “shaking like aspen leaves”. The leaves are rounded to cordate in shape with sharp points, and the leaf margin is evenly toothed. The petiole is thin, long and laterally compressed. Its range extends to the subpolar zone of Alaska and Canada to the warm to hot climates of the southern United States and central Mexico. The leaves of the black poplar grow to 5 to 12 centimeters in size, they are diamond-shaped or triangular in shape, and the leaf blades are long-pointed, with laterally compressed petioles. The buds are reddish brown and glabrous, the young twigs round. The male poplar flowers have 15 to 30 stamens, and the female flowers have two seated stigmas. The black poplar can reach a growth height of up to 30 meters and is widespread. It is native to continental Europe, northwest Africa, the Iberian Peninsula, Iran, Caucasus, China‘s Xinjiang Province, and Siberia. Poplars are popular as fast-growing trees on avenues.
Effect and application
The resinous winter buds (Populi gemmae) and bark (Populi cortex) of both poplar species are used. Less commonly used, on the other hand, are the leaves (Populi folium). The buds, three to eight millimeters in size, are surrounded by stiff-leaved scale leaflets. They are pointed cone-shaped, broad and shiny brown. The roof-tiled scale leaves are pointed, toothed, and unevenly formed. They are partially covered by a shiny, blackish-brown mass. Larger fragments of the buds, brown scale leaves and dry-skinned foliage leaves are used as a cutting drug. The odor is spicy to bitter, reminiscent of balsam and somewhat peculiar. The ingredients are phenolic glycosides in the willow bark with the main component salicin and similar substances. The fresh buds contain 0.27 percent essential oil, in the dried buds this substance occurs with 0.12 percent. This essential oil is composed of about fifty different components. Other active substances include flavonoids, galangin, chrysin, apigenin, rhamnetin, quercetin, isorhamnetin and kämpferol. Both poplar species have wound-healing, antiphogistic (anti-inflammatory) and antibacterial effects. Internal use is mainly based on salicin and salicin derivatives. These are broken down in the intestine into salicin alcohol, which after absorption by the liver and intestines oxidizes to salicylic acid, the actual active ingredient. The medicinal plant is used for hemorrhoids, skin lesions, sunburn and chilblains. Traditionally, poplar buds are used for rheumatism, urinary and respiratory tract infections, and chronic bronchitis. The components of poplar act as diuretics and expectorants (expectorant drugs). A positive effect has been noted in benign prostate enlargement. Homeopathy often uses the American trembling poplar. As a Bach flower essence, the poplar acts under the name “Aspen”. Both natural remedies are used to treat anxieties whose origin is unknown to the affected individuals. These diffuse fears begin with a vague feeling that disaster is approaching, but lacks any real basis.Individuals for whom the administration of Aspen is indicated fear that events will occur that are not good for them. The fears of the Aspen condition arise unpredictably both at night and during the day. Bach flower therapy and homeopathy take advantage of the origins of nature and treat the affected person with an appropriate antidote, which is attributed the same properties as the symptoms that occur. The name trembling poplar reflects very well the discomfort from which the patients suffer, they literally “shake like aspen leaves”. The poplar is very sensitive and reacts even to small drafts, Aspen patients are equally sensitive and very susceptible to all negative influences.
Importance for health, treatment and prevention.
Although the effectiveness is not scientifically proven for these applications, it is based on many years of experience. Both species of poplar are not toxic, but since it is a drug plant, self-responsible experiments are not recommended. However, as processed finished products such as tablets, tincture or drops, the ingredients of poplar are harmless. Interactions with other medications are not known. Contraindications are hypersensitivity to salicylates, perubalsam, propolis and poplar buds, which can cause allergic skin reactions. For external use, a semi-liquid preparation in the form of a tincture containing 20 to 30 percent of the plant components is used. It is applied to the skin, used as a poultice or bath additive. In home preparation, 3 to 6 g of the plant drug is mixed with 300 ml of water. When used as a bath, the plant extract is added to the bath water to treat hemorrhoids. In suppository form, the drug contains a water–ethanol-based thick extract.
