Growth features of Juniperus excelsa M. Bieb. in the conditions of field vegetation experiment and in greenhouse on the Southern Coast of the Crimea

¹ The Nikitsky Botanical Gardens – National Scientific Center of the RAS, Laboratory of Phytomonitoring, 52 Nikitsky spusk st., Nikita, Yalta, 298648, Russian Federation
² The Nikitsky Botanical Gardens – National Scientific Center of the RAS, Department of Natural Ecosystems, 52 Nikitsky spusk st., Nikita, Yalta, 298648, Russian Federation

^* Corresponding author: a.v.pashtetskii@gmail.com

Abstract

Different climatic conditions of the greenhouse and open ground determine the growth characteristics of Juniperus excelsa M. Bieb. During the studied vegetation period, three periods of trunk diameter growth were observed in the field vegetation experiment: in March–May, two growth peaks – at the first peak – 1% (0.68 mm), at the second one – 8.83% (3.72 mm). In July-August by 4.74% (1.69 mm), and in SeptemberOctober by 4.9% – (1.53 mm), the increase in the trunk diameter for 2019 was 18.96% or 7.62 mm. In greenhouse conditions, there were two growth peaks: in March-July, the first peak was an increase in d,% by 7.12% (1.11 mm) – while there was a slowdown in growth (April, 28 –May, 27) and (July, 13 – July, 25). The second peak is an increase in d,% by 5.06% and a slowdown in growth (November, 05 – November, 14). Total increase in d,% was 12.18% (1.899 mm). The increase in d,% in the conditions of vegetation experiment is 6.48% more than in the greenhouse conditions. Optimal and limiting values of the studied parameters of the environment and d,% for both research variants are found, and equations of nonlinear dependence between them are constructed. An increase in air temperature to 30-35°C causes a decrease in growth intensity. The research made it possible to determine the optimal and limiting conditions for the growth of this species in the conditions of the Southern Coast of the Crimea and the possibility of its introduction to other regions.