''Elephantorrhiza burkei'', commonly known as the elephant root or sumach bean, is a deciduous

shrub A shrub (often also called a bush) is a small-to-medium-sized perennial woody plant. Unlike herbaceous plants, shrubs have persistent woody stems above the ground. Shrubs can be either deciduous or evergreen. They are distinguished from trees ...

or small tree in the mimosoid clade of

legume A legume () is a plant in the family Fabaceae (or Leguminosae), or the fruit or seed of such a plant. When used as a dry grain, the seed is also called a pulse. Legumes are grown agriculturally, primarily for human consumption, for livestock f ...

s. It is native to southern Africa, where it is found on rocky slopes or ridges, in either woodland, grassland or scrubland. The species is named after the botanist Joseph Burke.

Description

The shrub or small tree has a dense rounded crown, and usually reaches between 1 and 3 metres in height. The grey bark turns brown and eventually blackish as the tree ages. The bipinnately compound leaves measure some 25 cm long, and bear 4 to 8 pinnae with 12 to 23 pairs of leaflets each. Their fragrant, creamy white to yellow flowers appear in early summer, and are pollinated mainly by the

African honeybee The East African lowland honey bee (''Apis mellifera scutellata'') is a subspecies of the western honey bee. It is native to central, southern and eastern Africa, though at the southern extreme it is replaced by the Cape honey bee (''Apis mellif ...

. Mature specimens carry their flowering racemes on branched stems some distance from the ground, and the pods are consequently conspicuous. The flower spikes grow from the leaf axils and are 5 to 10 cm long. Their elongate, flattened, brown to reddish brown pods measure up to 30 cm by 4 cm. The shape of their seeds is variable, from elliptic to almost quadrate.

Similar species

It is most similar to '' E. elephantina'', which has similar aerial parts, but consistently larger seeds.cf. Bothalia 11:252 (1974) Mature specimens of ''E. burkei'' especially, produce their flowering racemes on their branched stems, and the pods consequently appear in conspicuous positions some distance above ground. Seed shape varies considerably in ''E. burkei'', from elliptic to nearly quadrate when tightly compacted and laterally compressed in their pods. In either species the two pod valves will separate from their margin, which persists as a nearly continuous and empty frame, reminiscent of some ''

Entada ''Entada'' is a genus of flowering plants in the family Fabaceae, in the mimosoid clade of the subfamily Caesalpinioideae. It consists of some 30 species of trees, shrubs and tropical lianas. About 21 species are known from Africa, six from A ...

'' pods.cf. Palmer & Pitman, Trees S. Afr. 2:827, 1973 The two pod valves of ''E. burkei'' roll back and persist with their margins for many months, while the pods of ''E. elephantina'' generally disintegrate and disappear more rapidly.

Gallery

Elephantorrhiza burkei 2.jpg, Inflorescences Elephantorrhiza burkei 1.jpg, Green seed pods Elephantorrhiza burkei, peule, Skrikfontein, a.jpg, Seed pod valves separating

References

{{Taxonbar, from=Q15534624 Mimosoids Flora of Zambia Flora of Botswana Flora of Zimbabwe Flora of South Africa