Comparative analysis of the weed composition of a new energy crop (Elymus elongatus [Host] Runemark subsp ponticus [Podp.] Melderis cv. Szarvasi-1) in Hungary

A new energy crop (tall wheatgrass: Elymus elongatus subsp. ponticus cv. Szarvasi-1) has recently been introduced to cultivation in Hungary providing biomass as solid biofuel for energy production, without sufficient information for developing its proper weed control system. The characteristic species composition as well as abundances of weeds on energy grass fields were determined and were compared to other arable crop cultures. Weed-crop competition was also investigated in different soil conditions. As our results suggested, weediness of energy grass fields is more similar to that of perennial cultures like alfalfa than to other annual ones (cereals, row crops). Diversity of energy grass fields was comparatively low. Although no herbicide treatment was carried out, in each experimental plot cover of the energy grass increased significantly year by year with decreasing weed cover and species number. By the second year, the average weed cover dropped from the first year's value 48 to 17% and in the third year it did not exceed 4%. Different soil types had different effect on the temporal variation of weediness.