Willow (Salix sp.) species and clones have been selected in Finland, originally for basket willow husbandry, since 1910s. Screening for biomass willows started in 1973 by the Foundation for Forest Tree Breeding. Biomass willow research for energy started in 1978. The objective of the study was, based on theoretical background, on historical record of Finnish willow research between 1910-1980 and on analysis of the Finnish biomass willow research of the 1980s, a further selection of exotic and indigenous willows for energy and chemicals. Swedish selection of 63 exotics, mainly of Salix viminalis L. and Salix burjatica Nazarov, was screened in Kopparnaes willow research site in the southern coast of Finland, in 1983-1989. Salix viminalis showed both high yield potential and good crop certainty. The yield variations in Salix burjatica were big due to rust (Melampsora sp.) infection followed by lowered winter hardiness. Three recommendable Salix viminalis clones for southern Finland were found: 78-0-183 (Sweden), E7888 (Somero, Finland) and 78-0-21 (Sweden). Finnish indigenous species were screened based on collection (375 clones) in 1973-74 of the Foundation for Forest Tree Breeding and the Finnish 4H-organization (566 clones) in 1978- 79. Test sites were Suomusjaervi, Nurmijaervi, Kannus and Haapavesi. Salix myrsinifolia Salisb. was most productive of the indigenous willows. Five recommendable clones were selected: E6631 Kullaa, K2322 Heinaevesi, E6695 Hartola, V75 Mikkeli and V78 Loppi. The secondmost productive indigenous was Salix phylicifolia L., with most promising clones of E6682 Juva, V766 Pieksaemaeki and V754 Kuru. Based on willow hybridization studies in the Finnish Forest Research Institut, a considerable additional selection effect, boosted by heterosis, was found from the progenies. Further intraspecific crossings of geographically distant clones of Salix myrsinifolia, and selection from the progenies, are recommended. Based on research results from 1910-1990 Salix viminalis is recommended for practical biomass forestry applications in the southernmost agroclimatic zone of Finland. Salix myrsinifolia is recommended for further research and development in the other zones.
232.1 (Auswahl und Erprobung von Holzarten, -rassen usw) 238 (Baumanlagen, die eine besondere Behandlung erfordern (z.B. Pappelpflanzungen, Wurzelholz von Erica arborea usw.). Biomasse. [Einschl. plantagenmässiger Anbau und Schnellwuchsbetrieb sowie Angaben über dafür geeignete Baumarten. (Nur für allgemeine Darstellungen über diesen Sachverhalt. Einzelmassnahmen sind jedoch in erster Linie mit den ihnen entsprechenden Nummern zu klassifizieren, z.B. bei Astung mit 245.1)].) 176.1 (Dicotyledoneae [Siehe Anhang D]) [480] (Finnland)
