Research of Growth Dynamics of Selected Deciduous Trees for the Needs of Landscape Architecture

Abstract

The main target of the research was to compare the growth dynamics of woody plants in relation to their age, specifically in individuals up to 10 years after planting. Five fast-growing species (Fraxinus excelsior, Populus alba, Populus nigra, Ulmus laevis, Ulmus minor) and four control species (Acer campestre, Carpinus betulus, Prunus avium, Tilia cordata) were selected. The model site is part of the regional biocentre in Brno. It is a warm area with an increased groundwater level. The planting took place in 2011. Evaluation was done at the turn of 2016/2017 and included measuring the following attributes: the overall height of the specimen, the annual increment of the terminal shoot and the annual increment of six lateral shoots. The highest average values were observed in Populus nigra which, in the context of close results of individual specimens, can be attributed the overall highest growth dynamics. The average terminal shoot increment exceeded 50 cm in all species except for Tilia cordata; in Populus alba and Populus nigra it exceeded 100 cm. Generally, the values of Carpinus betulus, Prunus avium and Tilia cordata were mutually comparable and at the same time lower than the values of woody plants labelled as fast growing. The results for Acer campestre were close to the category of fast-growing species. It follows from the measured figures that Populus nigra showed the highest growth dynamics, Tilia cordata the lowest. On the whole, the species classified as fast growing (Fraxinus excelsior, Populus alba, Populus nigra, Ulmus laevis, Ulmus minor) reached higher results than trees with a standard speed of growth (Carpinus betulus, Prunus avium, Tilia cordata). An exception was Acer campestre which was with its results closer to Fraxinus excelsior and Ulmus laevis. For instance, the comparison of the average height of the slowest growing representative of fast-growing woody plants (Fraxinus excelsior 2.81 m) with the fastest growing species from the second category (Prunus avium 2.51 m) showed a difference of 30 cm in favour of the fast-growing category. The average height of Acer campestre amounted to 3.27 m. When comparing the maximum length of annual terminal shoot increment, the fast-growing woody plants exceeded 146 cm (Fraxinus excelsior), whereas in the control plants a maximum of 103 cm was reached (Carpinus betulus). The maximum length in Acer campestre was 170 cm. Despite this, only one of the used resources (Belke and Gaida, 1991) ranks this species among fast-growing woody plants.