Experimental Study on the Cold Hardiness of Flowering Cherries

Abstract

There are more than 10 species and varieties, and many cultivars, of flowering cherries that grow wild or are planted in Japan. Where as a fairly big number of them are being planted in the middle and the southern districts of Japan, the number decreases in the northern district. This report, which experimentally shows the cold hardiness of flowering cherries, is a fundamental study on their use in cold climates, made as a part of a series of investigations made on the utilization of flowering cherries.
As material for experiments, branches were cut from various flowering cherries that grow at Matsumae in Hokkaido about one month earlier than flowering, were frozen to-5°C, then kept at various temperatures for 4 hours, and were finally melted. Then the branches were put in vessels of water, and the state of tissues and organs were observed as they bud, fl ower, and grow leaves.
The results of the above observation were classified into 3 groups:(1) Those of which the flower buds and the leaf buds survived the temperature lower than-7°C. The camblum and wood of the branch survived-13°C. The branches flower or grow leaves.(2) Those of which the flower buds and the leaf buds could not or could barely survive-7°C, and the camblum of the branch could net survive-7°C.(3) The middle once were between the above (1) and (2). The group (1) is considered to have a strong cold hardiness, (2) weak, and (3) a medium cold hardiness. This conclusion can be an indication, as the actual cherries showed almost the same effects in their planting condition.
The results according to various cherries are as follows: strong “cold hardiness”... Prunus incisa, P. lanneciana “12 cultivars and var. speciosa”. P. nipponica var. kurilensis, midium... P. maximowiczii, P. lanneciana “7 cultivars”, P. verecunda var. yezoensis, P. pendula “2 cultivars and f. ascendens”, P. nipponica, P. yedoensis, P. parvifolia “cultivar” weak... P. yedoensis “cultivar”, P. lanneciana “4 cultivars”, P. miyoshii “cultivar”, P. verecunda “clutivar”, P. jamasakura “cultivar”.