Tree of the week: Senegalia galpinii – Monkey thorn – Apiesdoring – Molopa

Formerly known as Acacia galpinii, the Monkey thorn is a beautiful single-stemmed deciduous tree that can reach a mature height of 30m when growing conditions are ideal. This long-lived tree is fast growing with a trunk that can reach a diameter of 2m. It grows well in wooded grasslands, open woodlands and along streams. In South Africa, this tree occurs naturally in Limpopo and the North-West province where it is seen as an indicator of sweet veld.

Leaves of S. galpinii are binnately compound with twelve to forty pairs of fine hairless leaflets. The light green leaves have a small gland dot often seen on the petiole, but its position is variable. Senegalia galpinii is often confused with Senegalia polyacantha from which it can be distinguished by the gland on the leaf stalk. The gland is small in S. galpinii and large in S. polyacantha. S. galpinii also has paired thorns that are short and hooked; the thorns add protection for nesting birds which often prefer this tree for this reason. It bears creamy to light yellow flowers in spring and early summer. These are followed by reddish to purplish brown pods ripening during February-March.

This tree is a beautiful specimen for large gardens where there is enough space for it to display its round spreading canopy. The deciduous nature of the tree allows sunlight through in winter, making it ideal for a garden with a lawn and other shrubs that can tolerate semi-shade conditions. Roots of this tree are extensive; hence it should not be planted close to buildings. Senegalia galpinii is frost tolerant but severe frost often kills young tender branches. This tree can tolerate very hot and dry conditions, it makes an excellent shade tree on avenues.