Biomass analysis of industrial hemp “Felina 32” and the influence of plant height on its quality

Abstract

The “Felina 32” variety of industrial hemp (Cannabis sativa L.) is among the most popular cultivated varieties in Lithuania. In 2020 to 2021, the height of the above-ground portion of “Felina 32” ranged from about 1.37 to 2.52 m. In the less favorable year of 2021, 9.8% lower height and 28.5% lower mass plants grew. However, the impact of meteorological conditions on their comparative indicators was not confirmed. Two critical intervals were distinguished, which essentially influence the dynamics of plant growth: crop density of 90 to 150 plants∙m2 and plant height of 1.9 m to 1.99 m. Lower crop density results in larger plants, and plants taller than 1.9 m gain mass 2.58 times faster than shorter plants. In addition, industrial hemp of different heights is characterized by differences in the development of morphological parts. This directly affects the physical and chemical properties of biomass. It was determined that when the height of “Felina 32” variety changes, the heat value of biomass increases 0.342 MJ/kg, carbon concentration increases 0.70%, and ash content, sulfur, nitrogen, and chlorine concentrations decreased.