Combretum zeyheri

Combretum zeyheri, the large-fruited bushwillow or Zeyher's bushwillow, is a species of flowering plant in the family Combretaceae, usually found growing on acidic or sandy soils in tropical African savannas. A small to medium-sized tree, its roots are used as a source of material for making baskets and as a traditional medicine for haemorrhoids. Two interlocking wooden logs from a large-fruited bushwillow, connected by a notch, comprise the Kalambo structure. Located at Kalambo Falls, Zambia, and dating to roughly 476,000 years ago, the Kalambo structure is the oldest known wooden structure.