Floristic characteristics and features of use of species included in the genus hawthorn (Crataegus L.)

Hawthorn (Crataegus) is a plant consisting of various species of thorny shrubs or small trees belonging to the Rosaceae family. The genus Hawthorn (Crataegus L.) has 20 species in the flora of Azerbaijan and 20 species in the Nakhchivan Autonomous Republic: Crataegus pontica C.Koch., Crataegus orientalis Pall. ex Bieb., Crataegus meyeri Pojark., Crataegus szowitsii Pojark., Crataegus pentagyna Waldst. & Kit., Crataegus pseudoheterophylla Pojark., Crataegus cinovski Kassymova., Crataegus sanguinea Pall., Crataegus curvisepala Lindm., Crataegus caucasica C. Koch. Hawthorn species are found in various ecological zones, including mountainous, flat and semi-desert areas. The climatic conditions of each region affect the phenological stages of plant development. In the Nakhchivan Autonomous Republic, hawthorn is found in almost all altitude zones (800-2500 m). The greatest amplitude of distribution belongs to the species Crataegus orientalis. It is found in areas from the foothill zone to the subalpine zone (900-2250 m). In the middle zone, the species C. cinovskisii, C. szovitsii, C. Tournefortii, C. pojarkoviae and C. pontica are predominantly common. However, in some cases, the distribution zone of the species C. pontica goes down, and the species C. pojarkoviae rises to the high-mountain zone. The species Crataegus caucasica, C. rhipidophylla, C. pseudoheterophylla and C. zangezura are found almost from the low-mountain zone to the subalpine zone, and the species C. atrosanguinea and C. eriantha are found in the low-mountain and middle-mountain zone. The distribution zone of the species C. meyeri sometimes reaches an altitude of 2350 m. The flower lump of the hawthorn species, which is used as a food and medicinal plant, is used in the treatment of cardiovascular diseases and to regulate heart rhythm. Ripe fruits are also useful for lowering blood pressure in folk medicine. The fruits and flowers of hawthorn are used in medicine to treat cardiovascular diseases, circulatory problems and high blood pressure. The plant is rich in flavonoids, antioxidants and tannins, so it strengthens the immune system and has an anti-inflammatory effect. Hawthorn is also used as an ornamental plant.