Viability of common yew (Taxus baccata L.) plants in conditions of Kryvyi Rih

Abstract

Objective – to estimate the viability of Taxus baccata L. by complex of indices in Kryvyi Rih area and the possibilities of its use to green the industrial cities of Right-Bank Steppe.

Material and methods. The investigation objects are the plantations of T. baccata in the territory of Kryvyi Rih city as well as in the arboretum of Kryvyi Rih Botanical Garden of the NAS of Ukraine. These plantations were created over 30 years ago. Investigation methods: visual, morphometric, physiologic and biochemical, statistic.

Results. We ascertained that T. baccata occurs in Kryvyi Rih in the form of curtains or individual plants near administrative buildings, in parks or linear plantings along the highways at a distance of 5–10 m. In the arboretum of Kryvyi Rih Botanical Garden of the NAS of Ukraine, five decorative forms of this species grow successfully: ‘Aurea variegata’ (2 samples), ‘Dovastonii’ (2 s.), ‘Fastigiata’ (1 s.), ‘Globosa’ (2 s.), ‘Hibernica’ (3 s.). They were planted in 1980s. In 13 investigated city plantings, except of one, the form ‘Fastigiata’ occurs as bushes with 2–17 skeletal branches; the diameter of these branches near their bases is 3.39–11.6 cm. The height of the plants varies 1.3–5.0 m, crown diameter – 1.21–5.07 m. Crown needles are welldeveloped, and the proportion of the damaged needles is low. The annual growth rate was 22.2–38.5 cm, and the length, width and thickness of needles changed as follows: 21.3–29.4, 2.3–3.0 and 0.5–1.0 mm. The vital state of the vast majority of plants is good, as well as their decorativeness. The content of chlorophyll and carotenoids in needles of five forms of T. baccata from the arboretum of the Kryvyi Rih Botanical Garden in November varied within the limits: 1.48–2.83 and 0.54–0.92 mg/g of raw matter respectively, and in plants growing in the city: 1.69–2.81 and 0.61–0.89 mg/g of raw matter. The water content in needles was 52.2–60.8 %.

Conclusions. T. baccata in the conditions of a large industrial city of the steppe zone of Ukraine is characterized by high viability and decorativeness. It needs to be used much more widely in landscaping of cities of the Right-Bank Dnieper area.