Current state of plantations of state protective forest strips and problems of protective afforestation in the south of Western Siberia

Background. On the territory of the steppe low-forest areas of Western Siberia, plantations of state protective forest strips perform an important ecological, social, organizational and economic function. They have reached the age of 52-63 years, in some places they have disintegrated or are losing viability, in some places they are successfully developing and, in general, have great cognitive value for the development of protective afforestation.

The purpose of the work is to determine the current state of stands, to identify the most effective methods of their creation and cultivation in broadband plantations on the lands of the arid zone.

Materials and methods. The research was conducted on temporary sample plots using standard methods of plantation taxation, study of old-growth forest cultures and mathematical processing of field observation data.

Results. It has been established that the establishment of plantations with the use of fallow tillage and deep loosening, planting seedlings of the main species in clean rows at 2.5-3.0 m justified itself. The initial species composition has a great influence on their development. In the dry steppe in mixed and complex deciduous plantations there is early growth suppression and loss of the main species: Betula pendula, Populus ×sibirica, Ulmus laevis. Acer negundo and, especially, Malus baccata, introduced during planting both in the inner and downslope rows, are a sharp competition to them. Cutting out these species in middle age does not have a positive effect. Clean stands of both deciduous and coniferous species grow better and remain viable longer. The feasibility of creating wide strips of Ulmus parvifolia, as well as its use as a companion needs further study.

Conclusion. When creating protective plantations in dry steppe, the use of aggressive species as an admixture, undergrowth and edges should be excluded. On chestnut soils the breeding of pure Pinus silvestris cultures has a great prospect, on dark chestnut soils - Pinus silvestris and Larix sibirica. On chernozems of the region, pure stands of both deciduous and coniferous species have stable growth and high viability. Coniferous stands are characterized by greater longevity and marketability.