Abstract
In Europe, including Ukraine, a serious consideration is given to Pseudotsuga menziesii (Mirb.) Franco, as a prospective species for the creation of various types of plantations. The use of this tree species in plantations looks advantageous. The species composition of rare exotic arboreal plants, including P. menziesii, their representation and state of preservation were studied in the protected territories of the Steppe, Forest Steppe, and Ukrainian Polissya. Presently, it is relevant to study the age-class composition, quantitative and qualitative characteristics of P. menziesii, species condition and representation in various types of plantings in the protected areas of Ukrainian Polissya. The purpose of this study was to determine the distribution, status, biometric indicators, and age-class distribution of P. menziesii in the protected areas of the Ukrainian Polissya. Three research methods were utilized: field (route), analytical, and comparative analysis. In the Ukrainian Polissya, P. menziesii was first introduced in Vozdvizhenskyi Garden Art Park Monument (PMLA) in 1903. Mass introduction of the species into reserves in most locations took place in the 1960-70s. Among the areas that accepted introductions, 53.3% were concentrated in Volyn Polissya, 26.7% in Zhytomyr Polissya, and 20% in Novhorod-Siverskyi Polissya. The results of our research revealed that P. menziesii grew in 14 protected areas in groups, strip plantations, and as a single tree (a total of 107 specimens were found, of which 17% were P. menziesii var. glauca (Beissn) Franco). In the Radomska Dacha reserve district, P. menziesii plantation was created. In the age-class distribution, 53% of trees fell into 41-60-year-old category, with age categories of 1-40 and 61-80-year-old containing 33% and 7% of trees, respectively. P. menziesii produced viable seeds in 14 locations (seed production score varied between 2 and 5 at the maximum score of 5). In one other location trees did not produce seeds because reproductive age was not reached. Three locations were characterized by viable natural regeneration in the amount of 2 specimens per 1 m2 . Among seedlings, 83.2% were in good condition. The obtained results could be used to compare quantitative and qualitative indicators of P. menziesii in various types of plantations created in the Forest-Steppe and Steppe, representing the deciduous forests of Ukraine belt.