From 2006 to 2009, block template experiments were conducted to evaluate the biomass yield of four crop species-Amur silvergrass, Giant Miscanthus, Virginia fanpetals, and two Basket willow clones-at the University of Life Science, Lublin, Poland. The dry matter (d m) yields and number of shoots were determined each November, while biomass moisture levels were determined every November and March. The averages of the 4-year research datasets indicated that Giant Miscanthus produced the greatest biomass (16.5 t ha(-1) d m), while the two Basket willow clones (8.8-10.2) t ha(-1) d m, and Amur silvergrass (6.2 t ha(-1) d m) produced the lowest biomass. The mean yield of Virginia fanpetals was 13.0 t ha(-1) d m. The largest number of shoots per one m(2) were produced by Miscanthus species (55 units), with Basket willow and Virginia fanpetals producing half this amount (24-28 units). Similar moisture levels were obtained for Basket willow biomass harvested in autumn (49.5-54.6)% and winter (48.4-49.7)%. The biomass moisture levels of the other species in March was approximately two times lower (14-29)% than that in November (27-70)%. In a second experiment, the effect of varying plant density (10 000 and 30 000 plants per ha) on the yield of Giant Miscanthus was investigated. Double the biomass yield was obtained in crops with a density of 30 000 plants per hectare compared to 10 thousand. The higher yields were accompanied by larger, heavier, taller, but thinner shoots. (C) 2013 Elsevier Ltd. All rights reserved.