Деревна рослинність дендропарку Херсонського державного аграрного університету

One of the largest objects of landscaping on the territory of the city of Kherson is the Arboretum of the Kherson State Agrarian University (further the arboretum of KSAU). The harsh natural conditions of southern Ukraine caused the poor species composition of aboriginal tree plants. Therefore, on the arboretum territory the process of introduction, adaptation and naturalization of various types of ornamental plants has been carrying out for 70 years. In 1983, the Arboretum was given the conservation status of a park-monument of landscape architecture of local significance. Throughout the history of its creation, experimental research has been conducted on the introduction decorative species of trees and shrubs into the culture. Therefore, a comprehensive analysis of tree plants at the KSAU Arboretum, as well as the development of proposals for the formation of a range of tree plants for inclusion in the investigated object and for greening the city of Kherson are relevant to date.During the inventory of the species composition of tree plants in the Arboretum of KSAU, 126 species belonging to 87 genera, 44 families, 21 orders, 2 classes and 2 divisions have been identified. The Magnoliophyta division (120 species; 95.2%) prevails in the taxonomic structure of the arboretum dendroflor. The division of Pinophyta is represented by only six species (4.8%). The leading families of the given dendroflora are Rosaceae Juss. (32 species; 25.4% of the total species numnber), Salicaceae Lindl. (10 species; 7.9%), Caprifoliaceae Juss. (6 species; 4.8%), Oleaceae Lindl. (6 species; 4.8%), Ranunculaceae Juss. (5 species; 4.0%). The Families of Cupressaceae Bartl. and Fabaceae Lindl. are presented by four species each (3.2%). Other families are represented by fewer species. There have been discovered 10 life forms of tree and semi-tree plants in the Arboretum. The most numerous is a group of single-stranded deciduous trees (51 species; 40.5%) and erect deciduous shrubs (39 species; 31.0%). Most plants are erect and deciduous.The vast majority of species (111 species; 88.1%) are introduced from different parts of the world (Europe, Asia, and North America). Only 15 species of tree plants are aboriginal ones: Betula borysthenica Klok, Populus nigra L., P. alba L., P. tremula L., Quercus robur L., Corylus avellana L., Ephedra distachya L., Amygdalus nana L. and others. The analysis of the ecological structure showed that the groups of scioheliophytes (49 species; 38.9%) and heliophytes (44 species; 34.9%) predominate among the heliomorphs, xeromesophytes (56 species; 43.8%) are quantitatively predominant in the hygromorphs. Thermomorphs are represented by megathermophytes (68 species; 53.1%) and mesothermophytes (60 species; 46.9%). In relation to the trophy of the substrate, plants that grow on poor substrates - oligotrophy (86 species; 67.2%) dominate. Sozological analysis showed that in the KSAU Arboretum has plants from the Red Book of Ukraine: Betula borysthenica Klokov, the endemic of the Northern Black Sea and Syringa josikaea J.Jacq. ex Rchb., as well as species included in the List of Protected Plants in the Kherson Region: Clematis integrifolia L., Ephedra distachya L. and Quercus robur L. The dominant of formation of Amygdalieta nanae - Amygdalus nana L. grows on the territory of the Arboretum.Taking into account the climatic conditions of the city of Kherson, high solar activity during the summer period, low rainfall, temperature fluctuations during the year and seasons, as well as the microclimatic conditions of the Arboretum location, we propose to expand its range of tree plants in the future by including plants that combine decorative qualities with resistance to the environmental conditions: Magnolia soulangeana Soul.-Bod., Liriodendron tulipiferum L., Cornus alba L., Cotoneaster horizontalis Dcne. and C. multiflorus Bunge, Prunus serrulata Lindl., Cercis canadensis L., Picea pungens f. glauca, Acer ginnala (Maxim.) Maxim. and Acer platanoides L., Cotinus coggygria Scop., as well as to expand the range of glacial plants of Metasequoia glyptostroboides Hu et Cheng, Pseudotsuga menziesii (Mirb.) Franco, decorative forms of the genera Taxus L., Buxus L., Quercus L., Tilia L., Berberis L., Thuja L., Juniperus L., Chamaecyparis Spach and others. Decorative species that will grow successfully on the territory of the Kherson State Agrarian University Arboretum can be planted in other landscaping facilities of Kherson City. [ABSTRACT FROM AUTHOR]