The article concludes the issues of expanding the range of woody plants for greening the territory of Siberia and the sustainable formation of the urban environment using the example of the city of Bratsk. As a result, studies were carried out on the prospects of various forms and varieties of mountain pine for use in green construction and expanding the floristic diversity of cities and towns in Siberia. More than 200 specimens of mountain pine of different ages, in different growing conditions, belonging to 17 varieties and small forms of the species were examined. The research into the prospects of mountain pines was carried out from 2015 to 2023 in different areas of urban development, in green areas of various types and purposes. A large number of private collections of dendrointroducers were also examined in country houses, garden plots, and cottage plots. Private gardens in the absence of special scientific institutions offer ample opportunities for introduction studies of many foreign species. During many years of research, the degree of ripening of shoots of forms and varieties of mountain pine, winter hardiness, resistance to sunburn in early spring, ability to reproduce were determined, morphometric data of the studied specimens was collected and systematized, quantitative indicators of annual growth of shoots, which characterize the condition and prospects for the use  of these varieties and forms for landscaping the cities of Siberia were studied. The article provides data on the use of mountain pine in different growing conditions and use in various types of plantings. During the study, a classification  of life forms of mountain pines was developed, which subdivides all studied forms and varieties into full-sized, mediumsized, dwarf and miniature shrubs. This classification most accurately reflects the variational range of biomorphological characteristics of modern mountain pine varieties. Based on the analysis of the indicators of the integral assessment of the success of introduction, each form and variety was assigned a certain class of prospects, characterizing their use in green building. The forms and cultivars that received a high class of prospects as a result of the study are recommended for use in various forms of urban landscaping and private gardening in summer cottages and household plots.

The physiological state of Oregon grape or holly-leaved barberry (Mahonia aquifolium (Pursh) Nutt.) was studied in terms of the content and balance of spare substances in annual shoots. The relevance of the topic is due to the need for consistent expansion and optimization of the range of woody and shrubby plants used in the creation of urban artificial plantings of various functions and designs. The purpose of the study is to identify the content and ratio of starch and fats in the shoots of holly-leaved barberry during introduction to the Nizhny Novgorod region. The object of the study was the same-aged individuals of seed origin who reached the reproductive phase of ontogenesis. They are placed according to the same schemes in the arboretum collection of Nizhny Novgorod State University, whose geographical coordinates were 56°17'57.984"N, 43°58'59.988"E. Methodologically, the work was based on the principle of a single logical difference and was carried out in 2023–2024 using field stationary and laboratory methods. Starch was tested by color reaction to Lugol's solution, fats were tested by Sudan-III preparation. The phenotypic heterogeneity of the compared plants was established by the presence and balance of spare substances in the tissues of their shoots. Its manifestation was recorded both at the intraorganizational level and in the form of intraspecific individual variability. The content of spare substances in gross terms was estimated statistically: starch – from 7.20 ±1.20 points to 13.60±0.73 points; fats – from 6.20±0.663 points to 13.80±1.020 points; the sum of these substances was from 13.80±1.020 points to 23.80±0.875 points. The analysis of variance confirmed the significance of differences in them between individuals of seed origin: the Fisher criterion (F_op = 3.46...6.02) exceeded the tabular values. The effect of individual differences is great: in starch content – 45.10±13.04%; fat – 58.83± 9.78%; the amount of spare substances – 50.11±11.85%. The information obtained allows us to recognize the expediency of continuing the introduction of measures with magonia.

The taxation indicators of clones, families of plus trees of Scots pine and artificial plantations of the species were studied according to the main morphometric features of the trunks. An advantage was revealed in the growth of clone offspring of plus trees, in comparison with family offspring and trees in culturcenoses. Studies assessing genetic variation in Scots pine using ISSR markers revealed different levels of polymorphic loci. In the offspring of plus trees on forest-seed plantations, this indicator ranged from 67,71 to 70,83 %, and it ranged from 60,42 to 63,54 % in the stands of artificial plantations. – The generalized indicators for all investigated forest-seed plantations, by the proportion of polymorphic loci were 82,29 %, artificial plantings – 61,98 %, genetic diversity and Shannon index 0,239 and 0,332, respectively, which indicates a fairly high level of plant variability.

As a result of genetic studies, a high polymorphism of ordinary pine clones was revealed on forest-seed plantations in the Bashkir Сis-Urals. The obtained information on the genetic and phenotypic heterogeneity of clones of plus trees of this species is an important basis for scientifically substantiated selection and selection of valuable genotypes for certification of existing and creation forest-seed plantations of a higher genetic level.

The paper presents arguments about the increasing role and importance of the scientific approach  in modern landscaping, the importance of expanding the range of fast-growing breeds in complex urban planning  conditions.

A selection assessment in the collection of varietal poplar trees in the Arboretum of the Siberian State University named after M. F. Reshetnev was carried out. The arboretum populetum is represented to a greater extent by EuroAmerican black poplar hybrids, subdivided into male and female varieties. These are Euro-American hybrids that are promising for protective, industrial, forestry and landscaping purposes according to available research. Male varieties lead in three biometric indicators out of five (height, crown height, crown length), in terms of the projection diameter of the crown and trunk diameter they are practically not inferior to female varieties. A mass selection of varieties by growth rate was carried out. It was revealed that trees of Serotina variety are characterized by a higher height,  the largest trunk diameter was noted in poplars of Regeneratа variety. The larger diameter of the crown projection  was noted in the poplar of the Regeneratа variety; in terms of the height of the beginning of the crown and the length  of the crown, the Serotinа variety prevails. Individual selection of poplar specimens based on biometric indicators was carried out.

Most specimens of populetum are trees of I and II class height, class III height is singular; the predominant form of the crown is “narrow”, most specimens are characterized by a crown extent class of “long”. Four categories of viability were identified. Most specimens of poplar varieties are characterized by category “2” (weakened), the only variety with observed category of viability “1” (healthy) is Robusta.

The longest growing season was recorded in the poplars of Robustа and Moniliferа varieties (181 and 189 days, respectively). Varieties characterized by early and late beginning and end of vegetation have been established.

It is believed that the basis of heterosis is the genetic diversity of parents in terms of biological properties, structural, morphological, functional characteristics and origin. For the first time in coniferous breeding, the principle of heterogeneity was experimentally confirmed by us when studying the growth of 35-year old subalpine (1640 m above sea level) intra- and inter-belt hybrids of Siberian cedar from Northeastern Altai, tested in the zone of coniferous and broadleaf forests of the Bryansk region. They were obtained by pollination with ordinary, pure pollen from the parents. Individuals with somatic heterosis have been identified in fast-growing families in partner combinations that differ dramatically in several highly genetically determined properties, primarily in the type of sexualization that determines the entire course of body development.

This article presents the results of studies in the southern part of the broadleaf forests and forest-steppe subzone (Voronezh region) of 38-year-old mountain taiga (1100 m above sea level) growth hybrids of Siberian cedar from the Gornoaltai region obtained by pollination with a mixture of parental pollen, differing in the type of sexualization, yield, growth rate, structural characteristics of the crop, pollen productivity. Increased growth and a large number of fastgrowing individuals in families have been established when pollinated with a mixture of pollen from parents of different biological qualities. With significantly the same placement area, they outperform the same–age hybrids from crossing parents of the same female sex type by 1.6–1.8 m in height or by 14–19 %, in diameter – by 32–34 %. A genotype with somatic heterosis was identified: 17 % true, 26 % hypothetical. Its morphological indicators, reflecting the depressing effect of the vigorously growing central shoot on the lateral ones, are the increased number of medium and thin branches in the whorls extending from the trunk at a gentle angle (80–90°). As a result, it was found that a mixture of pollen from trees of different sexual types is an indicator of the biochemical diversity of partners, as the basis of heterotic breeding.

The article considers the methodology of construction of the discharge table of volumes for greenbark maple growing in the second tier of coniferous-broadleaved forests. The research was conducted based on the materials of the state forest inventory. The object of the study was 77 model trees. The regression relationship between height and diameter was studied. The averaged values of heights are expressed in indices relative to the height of the base thickness step. It is described by a 3rd order parabola equation. The height scale is represented by a family of curves obtained from a single centerline by stretching and compressing it. The height table is supplemented with trunk volumes. Stem volumes are defined as the product of height, diameter and empirical species number. The comparative analysis of productivity of plantations of greenbark maple, yellow maple and small-leaved maple was carried out on the basis of GIL materials.

The article provides the analysis of literary data characterizing the feasibility of conducting breeding studies to increase apple tree varieties. A brief description of the varieties used for hybridization on the territory of the Botanical Garden named after Vs. Krutovskiy is given. Apple trees include both summer and winter varieties. Summer varieties include: Arkad stakachchatyy, Bely Naliv, Grushovka Moskovskaya, Zolotoy thorn, Medovka, Papirovka; winter ones include Antipaskhalnoe, Arkad winter, Bismarck, General Orlov, No. 22. These varieties grow in a creeping form in the upper part of the garden (№ 5, 6, 36, 37, 48, 49, 52, 54, 54a, 65, 76, 76a) and in an open form in the lower part of the garden (№ 6-1, 6-3, 7-7, 9-7, 12-1, 19-8, 19-10, 21-3, 29-4). Research was conducted on the fruiting of apple trees and their differences in the size of the fruits (height, diameter, weight), the number of fruits on the tree were established. It was found that fruiting of summer varieties in a creeping form varies from 5.3 to 41.1 kg and from 2.4 to 39.4 kg for winter varieties; fruiting of summer open varieties fluctuates from 2.2 to 30.4 kg, and for winter varieties it fluctuates from 10.6 to 48.1 kg. The height of the fruit of the compared varieties growing in a creeping form, varies from 3.6 to 6.4 cm for summer varieties and from 4.1 to 6.2 cm for winter varieties; the height of open summer varieties varies from 3.7 to 5.5 cm, and for winter varieties it varies from 4.6 to 5.2 cm; The diameter of summer varieties fluctuates between 4.2 and 5.7 cm, while that of winter varieties fluctuates between 5.3 and 6.1 cm. The average fruit weight of summer varieties of creeping form varies between 31.1 and 108.7 g, while that of winter varieties fluctuates between 53.5 and 81.6 g; for open trees, the fruit weight of summer varieties fluctuates between 40.1 and 70.3 g, while that of winter varieties fluctuates between 60.3 and 80.9 g. Trees were selected for their further use in hybridization to develop varieties characterized by increased productivity and large-fruitedness. Specimens that combine two indicators of fruit (productivity and weight) are of great value: № 52 Antipaskhalnoye, № 54a Bely Naliv and № 12-1 General Orlov.

Identification of quantitative and qualitative transformation of ground cover plants under the influence of changes in ecotope conditions during the growth and development of a stand is of great importance for determining ways to restore forest phytocenoses. At this stage, foresters have no doubts about the need for a phytocenotic approach to the study of phytocenoses of natural and anthropogenic origin as a complex biological system. 

The purpose of the research was to study the dynamics of the formation of living ground cover of cultivated soil of forest crops in the northern part of the East European Plain. 

The objects of the study are forest crops of Pinus sylvestris L. and Picea abies (L.) H. Karst. of 2000–2001 years creation.

It is noted that tillage significantly affects the diversity of forest species in the ground cover. Tillage with the PLD1,2 plough leads to a significant reduction in the forest group of plants compared to areas treated with the PLP-135 plough. The greatest changes in the living ground cover were revealed at the site of reconstruction of deciduous young growth with soil treatment by PLP-135. 

As a result of the research, it was concluded that there is a gradual displacement of meadow species by an active forest group of plants. To a greater extent, changes occur due to the reduction of less stable inactive and low-active species, thus, the transformation of the ecological and cenotic structure of the flora occurs after anthropogenic disturbance in the direction of restoring the original structure of the forest environment

Various types of shrubs are widely used in landscaping of Russian cities, and in particular, in Krasnoyarsk, they perform sanitary-protective and aesthetic functions. At the same time, urban plantings located in the zone of atmospheric pollution are weakened, which is manifested in a more sparse crown, small leaves, loss of biological and mechanical viability, premature drying. In addition to the general impact of negative factors of the urban environment, factors are added that should contribute to increasing their stability: incompatibility, mechanical damage, etc. The technogenic load on landscaping objects was assessed as an integral indicator, based on the analysis of environmental factors affecting changes in the phytoenvironment. The study found that plantings grow in “tense” conditions on 2 landscaping objects; “conflict” – on 15 objects and “critical” – on 4 objects – these territories relate to highway spaces in areas of traffic jams, intersections and main highways. In all the studied greenery objects, the smallest decrease in the IHC was noted for Hungarian lilac, which ranged from 15 to 31 % depending on the growing conditions and is explained by both the stability of this species and its location in groups and arrays. The maximum decrease in the IHC in conflict and critical growth conditions from 31 to 42 % is observed for Tatar honeysuckle, these plants mainly grow singly or in small groups. Caragana arborescens, cotoneaster lucidus and currant two-spined have intermediate values, while they are located in this order by the decrease in the IHC. Thus, the choice of plants for creating greenery objects in areas with different levels of technogenic pollution should be based on analysis and scientifically based recommendations. As shown by the studies, the vitality index is a sensitive marker reflecting the impact of the environment on the condition of shrubs.

The introduction of woody plants makes a significant contribution to solving one of the most important problems of the region – improving the comfort of northern cities.

There are various methods of introduction used in practice. The main ones are: the stepwise method, the method of introduction by genus or generic complex, the method of phlorogenetic analysis, etc. In the case of the method of introduction by whole denroflora, the similar climatic conditions of the regions allow us to assume the successful introduction of woody species.

The purpose of these studies is to determine the breed composition and systematic structure of species of North American origin and to characterize them on the basis of a complete inventory assessment of the plantations of the Arkhangelsk agglomeration.

It was revealed that there are 53 species of arboriflora in the plantations of Arkhangelsk, of which 24 are trees and 29 are shrubs. The dendroflora of Novodvinsk and Severodvinsk is represented by 28 and 32 species, respectively.

As a result of inventory work carried out in public plantations, it was found that 11 species of trees and shrubs native to North America grow on the territory of the Arkhangelsk agglomeration.

In the conducted study, Siberian spruce plantations in six districts of Krasnoyarsk were evaluated, which resulted in the discovery of a very low yield of female cones. In three districts, the formation of cones on spruce was not detected at all. In other areas, cones were formed with average seed productivity, but with very poor seed quality, most of which were affected by conobionts. The introduction of full-grain seeds of Siberian spruce into culture in vitro led to the formation of callus cultures. The authors note that the selection of donor trees with high yields is necessary for the induction of somatic embryogenesis. Thus, the key topic of the article is the problem of low yield and quality of Siberian spruce seeds in the conditions of Krasnoyarsk, as well as approaches to improve this situation by introducing full-grain seeds into culture in vitro.