Common hazelnut, also known as filbert, is a deciduous shrub or tree from the genus Corylus in the family Betulaceae. This variety is characterized by high shade tolerance and adaptability to various soils, thriving on clay and sandy soils, and is resistant to wind and frost. Hazelnut bushes form attractive, lush crowns with large leaves, making the plant appealing for use in gardens, living hedges, and slope landscaping. Flowering begins early in spring, before leaf emergence, when golden staminate catkins up to 5 cm long appear on the plant. Hazelnut is monoecious, with both staminate and pistillate flowers occurring on the same bush. Hazelnut fruits are oval or spherical nuts about 2 cm long, enclosed in a light-green, hairy involucre. Each fruit cluster may contain up to 30 nuts, though typically 3–4 are present. Hazelnut bears fruit annually, making it a valuable plant for cultivation. Hazelnuts are widely used in the food and confectionery industries for producing halva, oil, chocolate, and candies. In addition, hazel wood is used to make furniture, baskets, wickerwork, and canes, while bark is used in leather tanning. Common hazelnut is found in mixed, broadleaf, and coniferous forests, where it acts as understory vegetation and grows on forest edges. Due to its resilience and decorative qualities, it is cultivated in many countries, including Turkey, Italy, Azerbaijan, the USA, Greece, and Crimea. Global hazelnut production reaches significant volumes, underscoring the importance of this plant as an agricultural crop and source of valuable nuts.
