Long roots get the deep moisture

Winter brings drought to the bushveld, reducing the short-rooted grasses to this. The trees, especially those with long taproots, source moisture far below. If the cold does not cause them to slow down into rest, some remain green for longer or throughout the season.

Many bushveld trees are deciduous, however. Some in winter, others in spring just before the new growth sprouts, while still other kinds remain evergreen, not yielding their leaves annually at all.

Individual trees of the same kind even differ in this. In some areas a certain tree species may be evergreen, while in a colder region it regularly goes bare in the winter months. 

And one may find trees of a kind on the same hill, one retaining its leaves, its neighbour shedding them. Cussonia trees on the southern slope of the Magaliesberg are notable for this.