Yields from commercial short rotation willow plantations

There have been many studies concerning the actual yields from short rotation willow plantations. In Europe up to now, only Sweden has developed a large enough programme based in willow biomass production for bioenergy, covering around 16 000 ha. Those are not research plots, but commercially managed plantations, and offer the first large enough sample of yields as well as a lot of information and experience about the development of such crops.

This is what we have studied in this publication "Yield models for commercial willow biomass plantations in Sweden" published last year in Biomass and Bioenergy. The most important finding has been the large effect that management practices have on the productivity. Also, we have found that cereal yields can serve as a good proxy for the prediction of willow productivity. We will continue this line of research, and any feedback is very welcome.

MOLA-YUDEGO B, ARONSSON P. 2008. Yield models for commercial willow biomass plantations in Sweden. Biomass and bioenergy 32(9):829-837.

Abstract

A yield model for willow plantations for bioenergy production in Sweden was developed based on recorded production of 2082 commercial plantations during the period 1989–2005. The model predicts yield for the first, second and third harvest using oats (avena) production as agro-climatic index. The mean annual yields were 2.6, 4.2 and 4.5 oven dry tonnes (odt) per hectare during the first, second and third cutting cycles, respectively. The yield correlated inversely with the length of the cutting cycle. The results of the study show significant differences between growers, which suggest the importance of proper management in the establishment and tending of the plantations. Model estimates for 25% of the best growers vary from 4.0 to 6.3 odt ha−1 yr−1 in 5-year-rotation plantations during the first cutting cycle, and from 5.4 to 7.1 odt ha−1 yr−1 in 4-year-rotations for the second cutting cycle. The proposed model can be applied in policy making and for management planning.

Keywords
Growth and yield; Bioenergy; Mixed models; Management