Common hazel, or hazel (Corylus avellana), belongs to the birch family. Cultivars of hazel, which are of industrial importance in the south of Russia (the Black Sea coast of the Krasnodar Territory), are known as hazelnuts. In the wild, hazel thickets are widespread in southern Russia, in non-chernozem areas, in the middle Volga, in the mountainous regions of the Caucasus. It is also found in Bashkortostan, Tatarstan, the South Urals, the Kirov region, and the Perm Territory.
Fruits are considered a highly valuable product - they contain in a concentrated form all the nutrients necessary for the body: proteins, fats, carbohydrates, vitamins of group A, B, C, D, E, P, K, as well as a number of macro- and microelements (iron, potassium , calcium, magnesium, manganese, sodium, sulfur, phosphorus, chlorine, zinc).
Common hazel belongs to monoecious plants, but with dioecious flowers, that is, male and female flowers are formed on the same plant. Male flowers are collected in drooping inflorescences - catkins, soft, yellow and similar to the catkins of birch, alder. They are laid in the season preceding flowering in June, July and in autumn they are already formed and are clearly visible. They hibernate and bloom in early spring. The pollen is carried by the wind.
Female inflorescences are hidden inside special buds and consist of very small densely spaced flowers. They also form in the previous season. They are not visible. During flowering, the leafy scales at the top of the female inflorescences (having the appearance of buds) move apart and a bunch of bright red or dark red stigmas protrude. It is they who catch the pollen carried by the wind.
The fruits ripen in the second half of August - early September. They are collected in a group of 2 to 5 pieces. The fruit is a single-seeded nut surrounded by a wrapper (ply). The envelope consists of two dissected or lobed leaves on the top, light green, pubescent, goblet. Fruits of various shapes - round, oblong, angular, more or less flat-compressed, mostly small, 10-15 ml in height and larger - 20 mm. At the Sverdlovsk horticultural selection station, selected forms with a fruit height of 18-22 mm were identified among the seedlings.
The wild-growing common hazel is a branchy, root-sprouting shrub with a large number of stems, 10-20 or more, 3-4 m high. When seed propagation, it begins to bear fruit for 6-7 years, for vegetative propagation earlier - for 4 years. To improve cross-pollination, it is recommended to plant at least two plants of different shapes.
Hazel grows on any soil, but it develops more successfully and bears fruit on more fertile soil. Moisture-loving, but does not like excess moisture, requires moderate drainage. It can tolerate a little shading, but it bushes better in an open sunny place and the yield is higher. Winter hardiness is relatively. It can withstand frosts down to -30 ...- 35 ° С. In particularly frosty winters with temperatures below -40 ° C, it can freeze out to the level of snow.
The distance between the plants when planting is 3-4 m. The roots of the seedling are pruned before planting, carefully straightened in the planting pit and covered with earth. They are planted at the level of the root collar, do not deepen, otherwise the bush will grow poorly and the beginning of fruiting will be delayed for 2-3 years. After planting, the plants must be watered and mulched.
With the advent of root shoots, they begin to form a bush. 6-10 of the strongest and most well-located shoots are left. The bush should not be thickened - the illumination worsens, the yield decreases. In subsequent years, in the spring, thinned bushes are thinned, if necessary. With proper care, hazel bears fruit well for 20-30 years, after which fruiting decreases. They begin to rejuvenate the bush. Rejuvenation consists in replacing old skeletal branches (stems) with new ones that have grown from young growth. Such a replacement can be gradual, when, over several years (6-7), the old trunks are alternately replaced in the bush with new ones.When rejuvenating, the stems are cut as low as possible. Rejuvenation and pruning should be done in early spring, before the leaves open.
When thinning, it is not recommended to do very strong pruning. The more branches there are on the trunk, the higher the nut yield. It is also not recommended to shorten annual growths, as fruit buds and catkins are formed on them. Excess growth, when it appears, should be removed as low as possible. The longevity of hazel, due to the intensive formation of overgrowth at the root collar, reaches 100-150 years, is practically unlimited.
Hazel is also used for decorative purposes, thanks to the large dark green foliage, painted in autumn in bright yellow and red tones. Red-leaved forms are popular, but their winter hardiness is lower than the forms of wild forest hazel. Used in high hedges, alleys, single and group plantings.