PRELIMINARY RESULTS REGARDING YIELDS OF VIRGINIA MALLOW (Sida hermaphrodita) AND CUP PLANT (Silphium perfoliatum) IN DIFFERENT CONDITION OF EUROPE

This paper presents the results of a field study on the growth and yields of two innovative energy crops, Virginia mallow (Sida hermaphrodita L.) and cup plant (Silphium perfoliatum L.) tested during the SidaTim project in Poland, Germany, Italy and the UK. Both plants are originally native to North America and they are perennial energy crops. Both species flower over a long period in summer and provide abundant pollen and nectar for pollinating insects. During SidaTim, both were tested for biomass yield in different agro-ecological conditions and as a biogas substrate. Biomass production varied substantially depending on the site. The biomass produced by Sida and harvested for direct combustion, after all growth had finished, ranged from ca. 7-10 Mg ha-1 in the second year to ca. 6-11 Mg ha-1 in the third year of growth. The biomass yield of Sida harvested at the beginning of the flowering period for biogas production varied between ca. 9 to 20 Mg ha-1 in the third year of growth. Silphium tended to yield greater biomass for biogas production than Sida. The yields for Silphium were between 10 - 27 Mg ha-1 depending on the year of growth and the site.