The average yield of a crop of miscanthus it is about 15-25 tons of dry matter per hectare of land every year, with peaks of 30 t / ha / year. From the water point of view, the efficiency in the use of water in optimal conditions is higher than that of the common cane (another of the so-called energy crops) with an estimated dry matter production of 11-14 grams per liter of water. 'water. These values refer to the Miscanthus Giganteus genotype.
Optimal production levels of miscanthus were obtained with a planting density of about 20 thousand rhizomes per hectare of land (the figure is from Veneto Aricoltura), even if on average the crops have a density of no more than 12-15 thousand rhizomes per hectare. This mainly depends on the fairly high purchase cost of the propagation material.
The biomass of miscanthus it is preferably harvested in late winter, after most of the leaves have spontaneously fallen to the ground and before the first spring rains arrive. In this period the water content of the biomass of miscanthus it is usually less than 15% and a subsequent drying process is not necessary.
From the point of view of quantity, the annual biomass production of miscanthus it rises in the first four years, and then stabilizes from the fourth year onwards. The biomass produced in the first year, however, is scarce and is usually not collected, preferring to carry out a shredding in the field and leave it on the ground as a layer of mulch that protects the soil from erosion, helps to control weeds, keeps the soil moist avoiding the excessive evaporation and protects the rhizomes from the cold.
As for the fertilizer, the cultivation of miscanthus it does not require particular interventions, which can also be avoided, and in any case it depends on the original content of the soil in potassium and phosphorus. Normally in the first plant the soil is prepared with plowing at a depth of 30 centimeters followed by two harrowing. The rhizomes are usually transplanted with a modified potato transplanter capable of placing the plants to a depth of 15 centimeters.
Some 'technical' problems still unresolved concern the collection of miscanthus. If done with a mower-chopper-loader it involves the collection of leafless material, the biomass is clean because it does not touch the ground but the density drops. Harvesting with the mowing-packing system, on the other hand, allows to collect a part of the leaves that have fallen to the ground, increasing the density but producing a biomass of lower quality because it contains soil particles.
The miscanthus it is part of the so-called energy crops or dedicated crops, that is destined to give biomass for the production of energy, from which second generation biofuels are also obtained. From the botanical point of view, the miscanthus belongs to the grass family and is native to Asia.
Very interesting is theinformation leaflet on miscanthus created by the Agriculture and Food Development Authority of Great Britain, in collaboration with the Agri-Food and Biosciences Institute. The brochure offers a complete guide on all the best practices to be adopted to successfully cultivate Miscanthus and to optimize its yield, during all stages of its production. Also interesting is the estimated miscanthus production costs per hectare up to a simulation of the income statement. Finally, addresses and references of companies and government bodies that can provide more information on the cultivation of miscanthus.