General trends in studying of genesis of florae's adventive components

General trends in studying of genesis of florae's adventive component are reviewed. Analysis of adventive flora is connected with a number of difficulties, which are caused by the low level of integrity of the object and by the mobility of its borders. Studying of genesis of the adventive component assumes the definition of florogenetic and invasive status of species. The evaluation of florogenetic status on the territories of different rank has its peculiarities. Invasive status of species in relation to the time scale can be characterized with various degree of detalisation. Special studies of model territories of different levels should be carried out for the development of the concept of historical analysis offlorae's adventive components.