Canopy architecture and PAR absorption of Euphorbia cooperi in the Matobo Hills, Zimbabwe

Euphorbia cooperi, a tree-like succulent found in the Matobo Hills of Zimbabwe, exhibits a unique canopy architecture that optimizes photosynthetic surface area while minimizing water loss. This candelabra growth form allows the plant to expand its branch surface area as it matures, enhancing photosynthesis without significantly increasing transpirational water loss due to its heavily suberized trunk and concave branch morphology. Simulations suggest that while a square cross-sectional morphology maintains a stable surface-to-volume ratio with minimal photosynthetic benefit, deep concave flutes maximize surface area but may increase drought sensitivity. This study highlights the adaptive advantages of E. cooperi's structure in arid environments.

Rundel, P. W., Esler, K. J., & Rundel, T. W. (2018). Canopy architecture and PAR absorption of Euphorbia cooperi in the Matobo Hills, Zimbabwe. South African Journal of Botany, 114, 260–266. https://doi.org/10.1016/j.sajb.2017.11.023