The biology of Canadian weeds. 109. Cytisus scoparius (L.) Link

Abstract

Scotch broom (Cytisus scoparius [L.] Link.) is an exotic perennial, leguminous, deciduous shrub, which during the past century has greatly expanded its range along the Pacific and Atlantic coasts of North America, and in Australia, New Zealand, South Africa, Chile, Iran, and India. This shrub rapidly invades disturbed areas, forming dense thickets, which can suppress and inhibit native vegetation, including economically important conifer seedlings. The developmental characteristics whereby Scotch broom invades new sites include specialized stem photosynthesis, prolific seed production, longevity of seeds in the soil, and nitrogen fixation. Human activities such as planting along highways for beautification and prevention of soil erosion have accelerated the problem of rapid geographical dispersal. Various methods of control (chemical, manual, and biological) together with habitat, morphology, reproductive biology, growth and development are discussed. Key words: Cytisus scoparius, Ulex europaeus, Scotch broom, invasive weeds, bioherbicides, Fusarium tumidu