ADVENTITIOUS ROOT PRODUCTION AND SURVIVAL OF PURPLE LOOSESTRIFE (LYTHRUM-SALICARIA) SHOOT SECTIONS

Purple loosestrite, Lythrum salicaria, notorious for successful wetlan d invasions, is a target of control measures including methods which p roduce shoot fragments. We document rejuvenation of purple loosestrife shoot sections and discuss the potential for vegetative reproduction through these fragments. Cut shoots (5, 10, and 15 cm long) were maint ained in a greenhouse for four weeks. Approximately 80% of the shoots survived with production of adventitious roots and lateral shoots. Qua ntitative production of root biomass and lateral shoots was dependent on shoot length. Survival was not dependent on shoot length. Survival was greater among plants from drier habitats (100%) than from wetter s oils (53%) and could not be predicted by pigmentation changes or necro sis, From a management perspective, fragment removal must follow mecha nical eradication attempts in order to eliminate these vegetative prop agules and prevent incidental recolonization.