Productivity and reserves of Heracleum dissectum raw materials in the Khabarovsk region

The purpose of research is to study the productivity and develop accounting standards (productivity and possible collection) and harvesting of dissected hogweed (Heracleum dissectum Ledeb.) on the example of the Khabarovsk Region. The object of the study is the food raw material of the dissected hogweed. The laying of registration sites for the collection of food raw materials of hogweed was carried out on the territory of the Hekhcirskoe forestry of the Khabarovsk Region (5 registration sites 1×1 min size were laid). The study was conducted from 2019 to 2022. Hogweed dissected was evaluated by the method of model specimens. When assessing the yield by the method of model specimens, 2 indicators were established: the number of accounting specimens (plant stems) per unit area and the average mass of raw materials obtained from one specimen, the number of bud inflorescences on the plant was also taken into account. This method was used because individual specimens varied in degree of development. The mass of young shoots was determined by weighing in wet and air-dry conditions. The food raw materials of the dissected hogweed were dried to an air-dry state at 95 °C in a ShS-80-01 drying cabinet. The yield of raw materials in the air-dry state, expressed as a percentage, was obtained by the ratio of the mass of dry raw materials to the mass of freshly harvested. The data were processed using the analysis package of the Statistica application program. The yield of air-dry food raw materials of hogweed was 25 %, and bud inflorescences - 16 %. On one hectare of cenoses with the participation of cow parsnip, the yield of the product with 100 stems is 3-5 t/ha; with 500 stems - 7-8 t/ha. Hogweed dissected is represented by ash-elm, poplar, white birch, aspen and alder formations. Possible collection of hogweed dissected in plantations (0.3-0.4) at a thicket density of 0.5-1.5 pcs/m2 - 99-290 kg/ha; 1.6-2.5 pcs/m2 - 330-550 kg/ha; 2.6-3.5 pcs/m2 - 520-720 kg/ha. Possible collection in open spaces (0.1) - at the degree of density of thickets 0.5-1.5 pcs/m2 - 75-210 kg/ha; 1.6-2.5 pcs/m2 - 300-400 kg/ha; 2.6-3.5 pcs/m2 - 450-600 kg/ha.