An hypothesis predicting which woody species selected by elephant are at risk of local extirpation is based on an understanding of elephant digestive physiology, foraging ecology, attributes of individual plants and populations, and historical changes in ecosystems. Elephant select items rich in cell solubles relative to availability for achieving maximum throughput per unit time on account of their large energy requirement, hindgut fermentation with limited cell wall digestion, high passage rate, and inefficient recycling of microbial protein. Accordingly, diet is predominantly green grass and herbs in the wet season, green browse in the late wet and dry seasons, and bark and roots following leaf fall. Increased consumption of woody material indicates nutritional stress. Bulls graze more than cows and impact woody plants more when grazing deteriorates. Species vulnerable to extirpation by elephant are those: whose attributes predispose adults to pollarding, uprooting or ringbarking; adults coppice poorly, hence mortality occurs; mortality is not compensated by regeneration and recruitment owing to the impact of elephant and other agents; species have a restricted distribution; and poor dispersal ability constrains recolonisation. Threat of their local extirpation has increased because of an increased probability of encounter with elephant attributed to artificial boundaries that have constrained movement, and proliferation of water points that has reduced spatial refuges for plants and weakened density-dependent regulation of elephant populations. Degradation of grasslands, wetlands and riparian areas has forced elephant to subsist on woody vegetation for a longer period of the annual cycle. A reduction in water points should increase local elephant density and attendant density-dependent effects of increased foraging distance, nutritional stress, calf and juvenile mortality, and predation, and reduce reproduction. Eliminating human predation after 4000 years in some parks has contributed to the problem. Mitigation of the threat of local extirpation should concentrate on configuration of boundaries, water provision, simulated predation, minimum reserve size, and not pursue non-definable notions of elephant carrying capacity. Keywords: Biodiversity conservation, Foraging ecology, Population biology, Savanna, Water provision.