West Africa constitutes a hotspot region for both land use change and climate change. Land use change, and highclimate variability in this region negatively affect tree growth dynamics, ecosystem functioning and services. In the presentstudy, we assessed the impacts of climate variability on tree growth of Detarium microcarpum Guill. & Perr. and Tamarindusindica L., two Fabaceae woody species with high socio-economic significance in West Africa. In total, we collected 18 stemdiscs from dead trees of the two species in the South-Sudanian phytogeographic zone in Burkina Faso. The studied speciesshowed well-defined growth ring-boundaries demarcated by marginal parenchyma bands. Cross-dating was successful withindisc and within species, and enabled the construction of statistically robust tree-ring index chronologies. The chronologiesspanned 45 years (1974 − 2019) and 30 years (1990 − 2019) for D. microcarpum and T. indica, respectively. We found asignificant variation in tree growth rates (p-value < 0.05) between D. microcarpum (1.711 ± 0.491 mm year−1) and T. indica(2.613 ± 0.473 mm year−1). Pearson correlation analyses showed that the standard ring-width index for both species posi-tively correlated with total annual precipitation amounts (p-value < 0.05) and major seasonal precipitation (p-value = 0.05).However, no significant correlation was found between ring-width index and temperature related variables. These findingssupport that precipitation controls tree growth of D. microcarpum and T. indica in the semi-arid savannas of West Africa.Consequently, a decrease in mean annual rainfall in West African region may negatively affect tree growth rate and standdynamics of the studied species.

Savanna trees · Growth patterns · Climatic factors · Rainfall variation · Sudanian region · West Africa