Willow family – Salicaceae.
For therapeutic purposes, poplar leaf buds are used.
It occurs almost throughout Ukraine (not often in the Carpathians and Crimea). Grows in river valleys (more often in the floodplain), along the banks of oxbow lakes, lakes, on wet sands, mainly in the basins of the Dnieper, Seversky Donets, less often the Southern Bug, Dniester, not often in the Tisza basin. In places along river banks, together with white poplar – Populus alba L. forms groves stretching in strips 100-300 m wide on one or both sides of the river valley for many kilometers. Often planted on roadsides, in parks, within gardens, on the streets, etc. Grows in large numbers in Chernihiv, Kyiv, Poltava, Cherkasy, Dnepropetrovsk, Kharkov, Donetsk, Voroshilovgrad regions.
Stocks of raw materials are large. Dozens of centners of buds and dozens of tons of bark can be harvested annually.
Black poplar is a tree up to 30 m high with a rounded crown. The leaves are almost triangular or rhombic, narrowed towards the apex, blunt at the base, with a serrated edge, dark green above, pale green below. The flowers are small with bracts, unisexual, collected in inflorescences – earrings.
The plant is dioecious. The fruit is a capsule with numerous small seeds and a tuft. Blooms in April before the leaves open. The fruits ripen in late May – early June.
In Ukraine, there are other types of poplars, a particularly large variety of them in culture (planting in forests, on roadsides, streets, parks, yards), but only black poplar should be harvested. During the bud harvest period, plants can be distinguished by their bark and buds.
Harvest buds during flowering (April). To do this, cut off small branches with secateurs or saws and tear off the kidneys from them with their hands. Sometimes they are pulled with hands in mittens, but with all this, the raw material is clogged with flower buds. Harvesting is carried out during thinning.
After drying under canopies with good ventilation, the kidneys are dried in the sun, spreading a thin layer (1-2 cm) on cloth or paper and stirring occasionally. If they
spread out in a thick layer, drying is slow, the kidneys warm up and turn black.
According to OST 4286, the raw material consists of oblong-ovate, pointed, bare, shiny buds of greenish-yellow or brownish-yellow color, 1.5–2 cm long and 4–6 mm wide at the base. The smell is peculiar, balsamic. The taste is bitter. Humidity is not higher than 12%. In raw materials, no more than 10% of other parts of poplar (including flower buds 1%) and 1% of mineral impurities are allowed.
Dry kidneys are packed in bags weighing 35 kg. Store in dry, well-ventilated areas.
The kidneys contain essential oil, glycosides populin and salicin, malic and gallic acids, bitter resin, gum. They are used in ointments and infusions for the treatment of burns, gout, hemorrhoids, hair growth, and an extract from them is used to prepare poplar ointment used in dressings. The essential oil of the kidneys is used in the perfume industry.