Flowering Pollination, Self-Sterility and Seed Development of Chinese Jujube

JUJUBE, tsao, or Chinese date, Zi zyphus jujuba Mill., is a member of the Rhamnaceae, or buckthorn family. A deciduous tree native to northern China, it was cultivated in that country many centuries before the beginning of the Christian era. Although small-fruited seedling jujubes were planted in the United States as early as 1837, large-fruited varieties were not introduced into this country from China until 1908. As trees of large-fruited varieties came into bearing at the U . S. Plant Introduction Station, Chico, California, growers developed an interest in planting them, but interest waned when it became apparent that their fruits lacked acceptable quality and texture. Seeds of some of these varieties, sharply pointed at the apex, were a hazard to cattle and to some extent to man