Anatomical structure of the annual shoots axis of introduced Pterostyrax species due to their winter hardiness

The similarity of the anatomical structure of the axis of annual shoots of Pterostyrax hispida (Sieb. et Zucc.) and P. c o r y m b o s a (Sieb. et Zucc.) has established. One of the possible reasons for high winter hardiness of these plants in the introduction is a thick layer of cuticle, sclerenchyma on the periphery of the stem, and intense lignifications of histological elements of bark, wood and perymedulyar zone.