Lack of data on water use of key species of drylands constitutes an obstacle to understanding their role in hydrological processes in this environment. To elucidate seasonal variation in water consumption by Vitellaria paradoxa, the dominant species of parklands of the semi-arid areas of West Africa, we've measured its transpiration using heat ratio method (HRM) and seven potential explanatory variables. Sap flux was found to be significantly different among years with 0.64, 0.59 and 0.67 L h− 1 dm− 2 in 2008, 2009 and 2010, respectively. Sap flux was significantly higher in the dry (0.73 L h− 1 dm− 2) than in the wet season (0.53 L h− 1 dm− 2). Nighttime sap flux during dry season (0.48 L h− 1 dm− 2) was significantly higher than that of the wet season (0.20 L h− 1 dm− 2) and it contributes on average to 26% of daily sap flow with a maximum reaching 49%. The mean …

Nighttime sap flux  Physiological response  Sap flux  Shea tree  Vapor pressure deficit