The article discusses the effects of human-controlled florogenesis on stability and development of species composition in trees and shrubs in Southern Volga Uplands. The possible factors are studied. Based on analysis of various academic resources, it is stated that the research of species composition of new woody plants on the territory in question needs more careful attention. The article demonstrates the data on 86 new woody plants (trees, shrubs, woody vines) in Southern Volga Uplands found to the present date.