Knobthorn
Senegalia nigrescens

Family: Fabaceae

What it is like

A tree. It has knobs on the trunk. These have hooks. The tree grows 18-25 m high. It loses its leaves during the year. The leaflets are roundish and the leaves are twice divided. There are 3-4 pairs of divisions (pinnae) with one or two pairs of leaflets on each. The leaflets are 2 cm long by 1.5 cm wide. There are small hooked thorns on the branches near the leaves. The flowers have a sweet scent. They appear before the leaves. The whole tree is covered with creamy-white flowers. They are in spikes 9 cm long. The fruit is an oblong pod. It is green but turns a dark black or brown. It splits open after it falls off the tree.

There are about 1,350 Acacia species. Over 1,000 occur in Australia. This legume tree forms nodules. Also as Mimosaceae.

Where it is found

It is a tropical plant. It grows on flood plains in woodland. Plants are sensitive to frost. It grows in areas with a rainfall above 500 mm. It grows between 40-1,600 m above sea level. It is most common in the lowlands. It re-grows after fire. It can tolerate drought. It can grow in arid places.

Countries/locations it is found in

Africa, Botswana, East Africa, Eswatini, Malawi, Mozambique, Namibia, South Africa, Southern Africa, Sri Lanka, Swaziland, Tanzania, USA, Zambia, Zimbabwe

How it is used for food

The leaves can be cooked and eaten as a vegetable. The gum is eaten as a snack.

They are a famine food.

Edible parts

Gum, leaves, vegetable

How it is grown

Plants can be grown from seeds. The seeds can be soaked in cold water for 2 days then planted. They can be treated with hot water for a shorter time.

Trees are very slow growing. Trees can live for a few hundred years.

Its other names

Local names

Ajam, Caia, Cananga, Chinanga, Chubunge, Gakaunga, Isinanga, Katopa, Mkunkhu, Mokoba, Muguhunga, Muhotohoto, Mukaya, Mukuu, Mukwamba-nziba, Munanga, Mungandu, Mupumbu, Muzoo, Nachiculia, Namuno, Nhlope, Umkhayamhlophe

Synonyms

Acacia nigrescens Oliv.; Acacia passargei Harms; Acacia schliebenii Harms; Acacia pallens (Benth.) Rolfe;