Putievsky, E., Division of Medicinal and Spice Crops, Agricultural Research Organization, Post Haifa, Newe Ya’ar, 31-999, Israel
Ravid, U., Division of Medicinal and Spice Crops, Agricultural Research Organization, Post Haifa, Newe Ya’ar, 31-999, Israel
Snir, N., Division of Medicinal and Spice Crops, Agricultural Research Organization, Post Haifa, Newe Ya’ar, 31-999, Israel
Sanderovich, D., Division of Medicinal and Spice Crops, Agricultural Research Organization, Post Haifa, Newe Ya’ar, 31-999, Israel

Trees of bay laurel (Laurus nobilis L.) grown under cultivation reach the maximum content of essential oil in autumn and the lowest in spring. Young stems and old leaves have the highest content. Bay laurel produces more than 5 kg of fresh matter or more than 50 ml of essential oil per tree per year, from the fifth year of growth. The mono- terpene-hydrocarbons and the oxygenated components gradually change during the year, with a slight decrease in winter and spring. On the other hand, 1,8-cineol reaches its highest level in spring (more than 60% of the essential oil) and its lowest (40%) in summer. The content of 1,8-cineol in leaves and stems is very similar but there are some differences between these parts regarding the other fractions of the essential oil. © 1984 Taylor and Francis Group, LLC.