This article is a continuation of a series of publications covering the alien fraction of the flora of the Saratov region and its influence on the formation of the flora of the region. The work presents results of the inventory of twelve herbarium collections of species alien to Saratov region, being stored in the Herbarium of SSU (SARAT). These species are either widespread throughout the Saratov region, occupying extreme habitats, or are reliably known from a small number of locations.

The results of studies on the distribution of 30 alien plant species in the territory of 41 specially protected natural areas in the Bryansk region are presented. The role of invasive species in the vegetation cover of most studied areas is currently insignificant. In all specially protected natural areas, only Erigeron annuus (L.) Desf. and E. сanadensis L. were recorded; Oenothera biennis L., Acer negundo L., Bidens frondosa L., and Echinocystis lobata (Michx.) Torr. & A. Gray were often found. Among the most dangerous invasive species are Acer negundo, Arrhenatherum elatius (L.) J. Presl & C. Presl, Impatiens glandulifera Royle, Solidago сanadensis L., Cornus alba L., Zizania latifolia (Griseb.) Stapf. River valleys are the main natural corridor for the spread of alien species. The minimum number of invasions was noted in forest and swamp ecosystems.

It is for the first time for the Omsk region that the synopsis of alien vascular plants, including 252 species (subspecies) from 49 families is presented. For each species the time of occurrence (and the first record if available) and spread in the region are indicated. The largest number of species belongs to families Asteraceae, Brassicaceae, Poaceae, Chenopodiaceae, Fabaceae, Rosaceae, Lamiaceae and Boraginaceae. According to the time of occurrence, 55 species belong to archaeophytes, and 197 to coenophytes.

The paper provides information on effective modern methods of controlling the dangerous invasive species Heracleum sosnowskyi Manden. The «strengths» and «weaknesses» of the proposed methods are examined, the range, degree and effectiveness of their impact on the growth and development of this species are described. The proposed annual work plan to control H. sosnowskyi make it possible to effectively use human and economic resource potential, and will also allow controlling this invasive species quickly and avoiding extra costs.

In the territory of southeast Kazakhstan, 71 species of alien plants have been registered (42 taxa of woody, 29 herbaceous plants). Fungal diseases were previously found on 14 species of woody plants and on 7 herbaceous species. During additional mycological survey of the territory in 2021–2023, additional data were obtained for the mycobiota of alien species of vascular plants in the southeast of Kazakhstan. Diseases caused by fungi were found on Amorpha fruticosa L., Juglans regia L., Malus domestica (Suckow) Borkh., Ribes aureum Pursh., R. nigrum L., Lapsana communis L., L. intermedia M. Bieb., Symphytium сaucasicum M. Bieb. One more species of phytopathogenic fungi was identified on еach species: Acer campestre L., A. tataricum L. and Betula pendula Roth.

The habitats of Impatiens glandulifera Royle, Pistia stratiotes L., Vallisneria spiralis L., found in 2004–2021 in the city of Samara, are described. Impatiens glandulifera was registered for the first time for the flora of the Samara region among local coastal plants in 2004 on one of the ponds of Samara on Mirnaya Street. Pistia stratiotes was found for the first time for regional flora on September 17, 2006 in a city pond (near school No.154 of Samara) among thickets of Elodea canadensis Michx. and Typha latifolia L. growing at depths up to 50 cm. Vallisneria spiralis was first discovered within the region in the territory of Samara in September 2020 among thickets of aquatic macrophytes in the water area of cut-off lake of the Sok River.

Invasive plants threaten biodiversity and functioning of ecosystems all over the world, cause significant economic, ecological and social losses and even full-scale ecological catastrophes. In this regard, it becomes particularly relevant to develop methods for studying the peculiarities of plant distribution to identify patterns of phytoinvasions. The aim of the study was to analyze the results of the peculiarities of alien species distribution in various regions obtained using multivariate statistics methods. Promising application of data visualization methods for revealing the peculiarities of alien species distribution and invasion on macroecological data level (Western – Eastern Europe, Trans-Siberian Railway) and regional one was shown.

The results of studying the flora of solid waste landfills in six cities of the Yaroslavl region in 2000–2023 are presented. 177 alien plant species of 42 families were identified, among them 23 species recorded for the first time. The most representative were the Asteraceae family (31 species), Rosaceae (21 species) and Poaceae (16 species). The species richness rates vary from 35 to 118 alien plant species in different landfills. The spread of alien species is analyzed in 7 solid waste landfills.

One of the characteristic features of urban floras is their homogenization, synonymous with the loss of regionally unique species and reduction in functional diversity. In our work we examined the species composition of alien species in the flora of Russian cities to identify the contribution of this fraction to the homogenization and differentiation of urban floras. Alien species were classified into archaeophytes and neophytes according to the time of introduction (i.e., before or after 1800). The differentiation between the floras was quantified using the Simpson dissimilarity index. Archaeophytes reduce the beta-diversity of urban flora in the investigated region. Neophytes on the contrary contribute to the differentiation of the species composition of the studied urban floras. Species similarity of urban flora depends on the distance between cities – the more is the distance between cities, the lower is their species similarity.

The study of alien species, including invasive or potentially invasive ones, has been one of the important areas of fundamental and applied work in recent decades. The aim of our work was to identify alien species of woody plants in the natural communities of Almaty region, alien and invasive species saturation of the study region and to evaluate their potential invasive aggressiveness. The objects of research were the natural ecosystems of the Almaty region, confined to the Balkhash-Alakol and Zhongar-Alatau floristic districts. 37 species of alien woody plants have been identified in natural ecosystems, including two transformer species and 22 aggressive species with the ability to naturalize with a high capacity for seed and vegetative reproduction.