National Arbor Week takes place during the first week of September and as such we are looking at Ziziphus mucronata (Buffalo thorn) and Euclea pseudebenus (Ebony guarrie) that has been designated as our trees of the year for 2017. One common and one rare species are selected to be celebrated for their beauty and importance in the environment.
Ziziphus mucronata is this year’s common species. Medium sized with a rounded, spreading crown, the deciduous Buffalo thorn grows to a height of 4 to 8 m. The foliage is a shiny, dark green and the leaves turn yellow to orange before dropping in autumn. This is an ideal shade tree as it provides coolness in summer, but allows enough sunlight in winter to provide warmth. Small, yellow green flowers are produced from October to April and the nectar will entice many insects and birds to the garden. The fruit takes the shape of a round berry that ripens to yellow and then dark brown. It stays on the tree for a long time, even when the leaves have dropped and is eaten by birds and wildlife alike.
Ziziphus mucronata is one of the most adaptable trees in Africa. It has the ability to withstand intense heat and cold and grows in all types of soil. Drought hardy and frost resistant, the Buffalo thorn can be planted to form an impenetrable hedge and is a good choice for wildlife friendly gardens.
Euclea pseudebenus, also known as the Cape ebony is a rare species that is commonly found in harsh, stony and sandy desert or semi-desert conditions. Growing to a height of between 3 and 9 m, this evergreen tree has slender, drooping branches that are covered with very narrow, bluish green to gray-green leaves. The bark on the stems has a rough texture and is dark grey in colour. These stems are often hidden by the drooping branches which at the same time provide welcome shade in hot conditions. Small, inconspicuous flowers, greenish yellow to cream coloured, bloom from late winter to late spring. Male and female flowers occur on different trees and have a delicate fragrance. Fruit in the form of small, fleshy berries ripen during late summer and the berries turn from green to black as it matures.
The Cape ebony is well adapted to extreme, dry conditions. It has a tap root that reaches deep to collect moisture and the leaves hang down, minimizing exposure to the sun. The tree attracts birds, butterflies and bees and the foliage is often browsed by antelope and domesticated livestock such as goats while providing shelter. It must be noted that this tree is not readily available from nurseries.