Wood ash – green energy production side product as fertilizer for vigorous forest plantations
Latvian State Forest Research Institute ‘Silava’, Riga str. 111, LV-2169 Salaspils, Latvia
Notable amounts of wood ash containing plant macro and micronutrient elements in balanced proportions are produced in Latvia. If bioenergy production source product is plant material, and facilities are operating well, then ‘side product’ fermentation residues or wood ashes should not contain elements in toxic concentrations. Wood ash contains P and K which are lacking in acidic organic soils and could work as fertiliser as well as a long term liming agent, besides that, all micronutrient elements necessary for physiological processes are present in wood ash. Wood ash could also be used as ‘revitalization agents’ – fertilisers to improve the growth of plantation forests. The aim of this research is to find and describe the positive effect of wood ash fertilisers on Norway spruce (Picea abies) and other economically valuable tree species. Research results show positive wood ash application effect on tree growth and vitality within the first 4 years when used for recultivation and revitalization purposes. Recycling of wood ash (0.5–3 t ha- 1 before planting) for fertilisation of and Picea abies forest plantations are a sustainable and effective solution for the improvement of tree growth as well as an environmentally safe method of utilization of bioenergy production residues.