HARVESTING WITH TRADITIONAL MECHANICAL SYSTEMS OF HEMP GROWN UNDER WATER STRESS CONDITIONS, A TECHNICAL-ECONOMICAL EVALUATION

Hemp (Cannabis sativa L.) is a crop characterized by multipurpose applications (fiber, seed, inflorescence) the agronomic crop management and the mechanization system adopted for the harvesting are strategic choices as they definitively influence the final product purpose. In particular, the crop cutting followed by in the field drying/maceration demonstrated their efficacy in obtaining a product suitable for the next industrial fibers separation from the stem. The extremely dry climatic conditions that characterized the Italian agricultural areas during the 2022 spring-summer dramatically limited the development of the plants both in height and in the stems section. From the point of view of harvesting management, this aspect represented the opportunity to evaluate the use efficiency of a mechanized harvesting system that involves the employment of machines commonly used for the haymaking process. The different meteorological conditions that occurred in the two-year period 2021-2022 made it possible to evaluate the behavior of the crop in the different environmental conditions, the biomass yield obtained highlighted the susceptibility to water stress (rainfall absence) in the months of greatest crop development such as June, July and August. The technologies used for harvesting have confirmed their efficiency with low costs of up to 220 euros, including mowing with or without use of specific hemp machine, windrowing and baling. The reduction in yield can represent a limit when the costs per unit of harvested product reach the commercial value of the biomass produced, in the present experience it has reached 142 euro t wet product, a value that is difficult to sustain in the current hemp market.