The Monkey thorn is one of the largest Acacias, this beautiful single-stemmed deciduous tree is fast growing and can reach a mature height of 30m when growing conditions are conducive. The trunk of this long-lived tree 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 twice compound with twelve to forty pairs of fine hairless leaflets. The light green leaves often have a small gland dot 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. This tree also has paired thorns that are short and hooked; the thorns offer protection for nesting birds which often prefer this tree for this reason. It bears creamy to light yellow flowers before the new leaves 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 with enough space 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. It is also a valuable tree to provide shade for livestock and game during the hot summer months. 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 and is ideal for bonsai.
