Productivity of six varieties of basket willow in a three-year cycle of biomass harvesting

Purpose. To choose varieties of basket willow that are most suitable for cultivation in the Right Bank Forest Steppe and to find out the peculiarities of their accumulation of energy biomass. Methods. Measuring and weighing, mathematical and statistical. The results. The article presents the results of the study of growth characteristics and three-year biomass productivity of six willow varieties (ʹTordisʹ, ʹIngerʹ, ʹWilhelmʹ, ʹ1047ʹ (Gigantea), ʹ1057ʹ (ʹMarzencinskiʹ) and ʹ082ʹ (′Warm-maz′) on the leached chernozems of the Right Bank Forest Steppe of Ukraine. The highest average height of the plants was 517 cm in the cultivar ‘1052’. The cultivars ʹ1047’ (470 cm) and ′Wilhelm’ (445 cm) also had the highest average shoot lengths: 365 cm, 352 cm, and 377 cm respectively. The largest average diameter at the base of the shoot was in plants of the ′Wilhelm′ variety — 21.4 mm, in ʹ1052ʹ — 18.4 mm and in ʹIngerʹ — 17.9 cm, while the smallest diameter was in the clone ʹ082ʹ (15.4 mm). At the middle of the length of the shoots, the largest average diameter was also in the variety ′Wilhelm′ — 12, 3 mm, while the smallest (10.2 mm) — in clone ʹ082ʹ. Bushes of the studied cultivars on average had from 4.5 shoots in the variety ʹVilhelmʹ to 12.8 shoots in the variety ʹ1052ʹ. The biomass of the average bush was the highest (4.635 kg) in the variety ʹ1052ʹ, which is characterized by the maximum number of shoots per 1 bush. The lowest average weitht of one bush was in the variety ʹTordisʹ (1.475 kg), which has low indicators of mass of shoots and their number per bush. It was the number of shoots that had the greatest influence on the average weight of plants and, in general, on the productivity of plantations. Conclusions. The highest yield of dry above-ground biomass of three-year plants was in Polish varieties ʹ1047ʹ — 27.81 t/ha and ʹ1052ʹ — 26.06 t/ha, and the Swedish variety ʹIngerʹ — 23.77 t/ha, which indicates the prospects of their cultivation for energy biomass in the region of research. The biomass productivity was much lower in the varieties ′Wilhelm′ (13.61 t/ha) and ′Tordis′ (8.85 t/ha), the use of which is less appropriate in the studied region. It is advisable to continue the study of willow cultivars in order to clarify the dynamics of their yield during the entire period of plantation exploitation.