Consumption of flowers by the following four browsing ruminant species was monitored for two years in a southern African savannah: giraffe (Giraffa camelopardalis Linnaeus), kudu (Tragelaphus strepsiceros Pallas), impala (Aepyceros melampus Lichtenstein) and steenbok (Raphicerus campestris Thunberg). Flowers of Acacia nigrescens Oliver are an important food resource to giraffe in the late dry season. This is not necessarily deleterious to the reproductive potential of the plant however, as most or all African Acacia species bear high proportions of sterile flowers. Factors such as inflorescence structure and colour, pollen morphology and thorn structure suggest that one group of African Acacias could be pollinated by ungulates. Timing of flowering in A. nigrescens, and a close association between A. nigrescens and giraffe, indicate that giraffe could well be a pollen vector for this species.