The British flora which is representative of a large area of western Europe consists of approximately 3,500 species from 146 families. This list has been scanned for species suitable for biomass production. A number of families, notably theLeguminosae, Rosaceae and the Salicaceae, contain potentially suitable species which have not hitherto been investigated. Because of the importance of maintaining a self-supporting, and hence a renewable system, woody plants have a particular advantage. Financial considerations may be a constraint on long term investment, and hence short rotation forestry is considered a promising choice for the production of a renewable source of energy.