CARACTERÍSTICAS BIONÓMICAS DE LAS MALAS HIERBAS DE ORIGEN AMERICANO EN FRANCIA

Abstract

The species from America which are naturelized or subspontaneous in France settle mostly in pertubed areas. Anual type seems to be the most adequate. The comparation between species which have become weeds or no, shows that there are some prevalient characteristics such as: summer cycle, photosynthetic pathway in C4, previous weedy comportment in America. Though some species in C3, which are disseminated by wind and have a high seed production , may also be successfull. Fecundation type and level of ploidy do not seem to be of much importance to explain invasion.