Yield structure of energy willow as affected by cultivation technology
Authors: Sinchenko V. M. , Fuchylo Ya. D. , Hanzhenko O. M. , Melnychuk H. A. 
Published: December 2024

Purpose. Determining of the biomass yield structure of willow varieties ‘Ternopilska’ and ‘Tora’ as affected by technology of their cultivation under the conditions of the Right-Bank Forest-Steppe of Ukraine.
Methods. Field, laboratory, statistical. Experimental energy plots were established using cuttings of ‘Tora’ and ‘Ternopilska’ clones, planted in paired rows with a distance between them 0.75 m and distance between paired rows 1.5 m and 2.5 m. Three options of planting density of cuttings were used: 12, 15 and 18 thousand plants per hectare. The soil type for the experiment was fresh leached coarse chernozem. The investigated characteristics of the plants (height, diameter of shoots, mass of plants and their individual organs) were determined according to the commonly accepted methods in crop production.
Results. At the end of the first growing season, the viability of cuttings of the ‘Tora’ variety ranged from 88 to 93%, and ‘Ternopilska’ variety from 89 to 95%. The average number of shoots ranged from 2.2 to 2.3 per plant in ‘Tora’ and from 4.1 to 5.0 in ‘Ternopilska’. This index remained virtually unchanged during the study period and was not significantly affected by planting density or planting design. The average height of the plants in the first three years in all variants of experiments was higher in ‘Tora’. In particular, after the third year it varied from 524 to 604 cm, against 414–557 cm in ‘Ternopilska’. In both varieties, higher altitudes were observed at a row spacing of 1.5 m. The yield of three-year dry biomass in ‘Tora’ ranged from 25.1 to 34.7 t/ha, and in Ternopil from 16.0 to 27.9 t/ha, or on average for the year respectively: 8.4–11.6 and 5.3–9.3 t/ha. The dry matter content of willow biomass is influenced by the structure of the biomass, in particular, the proportion of second-order branches in it. The percentage of branches in the biomass of ‘Tora’ varies from 13.7 to 28.0%, depending on the variant of the experiment, and from 15.3 to 17.2% in ‘Ternopilska’. In addition, dry matter content decreases with decreasing planting density. The maximum yield of energy from 1 ha (up to 631.9 GJ/ha in the first three years) was obtained in ‘Tora’ under the 0.75 x 1.50 x 0.75 m planting layout and planting density of 15 thousand cuttings per 1 ha. Conclusions. On the leached chernozem of the Right-Bank Forest Steppe of Ukraine, of the two studied willow varieties, ‘Tora’ marked higher growth and productivity indicators. After the third year of cultivation, the average height of the plants in its experimental variants varied from 524 to 604 cm, and in ‘Ternopilska’ from 414 to 557 cm; yield from 25.1 до 34.7 t/ha, and in ‘Ternopilska’ from 16.0 to 27.9 t /ha, which averages 8.4–11.6 and 5.3–9.3 t/ha, respectively. The maximum output of energy per 1 ha (up to 631.9 GJ/ha in the first three years) can be obtained by growing ‘Tora’ variety under planting design 0.75 x 1.50 x 0.75 m and the planting density of 15 thousand cuttings per 1 ha. With the decrease in planting density in the biomass of willow plants, the moisture content of the biomass and the percentage of branches increases, which negatively affects the dry matter and energy content.