POLYMORPHISM OF HAZEL SHOOTS IN THE NATURAL POPULATION OF THE NORTH-WESTERN CAUCASUS

In the population of common hazel in the north-western Caucasus, we studied the polymorphism of shoots by their shape, average diameter of the three main trunks, number of shoots up to 4-year-old and older, and according to growth rate of annual shoots. The plants grew at an altitude of 250–1 500 m A.S.L. Total of 450 individuals were examined. In the population, the species was dominated by straight – 47.88 % and curved shoots – 41.43 %; cranked and weeping were less common – in 10.69 and 0.22 % of cases. In hazel bushes, the number of shoots under the age of 4 inclusive reached up to 98 pieces, of which 79.14 % had from 7 to 20 shoots. The number of shoots aged 5 in 92.91 % of cases was 5–25 pcs. There are also bushes with a single trunk. Their share was 0.79 %. The vast majority of plants 83.07 % have an average diameter of 3 main shoots (3.42–8.69 cm). Some individuals develop a diameter of up to 28 cm. The length of growth of annual shoots varied from 3.4 cm to 21.6 cm, the coefficient of variation was 42.87 %, which indicates a significant variety of the trait.