Southern African Trees

Wrapping your head around the diversity of plants in many parts of the world can be daunting. In total, there are somewhere between 250 000 and 400 000 flowering plant species, so it is difficult (if not impossible) to learn every one. So, how does one begin to learn the names of so many flowers and trees and shrubs and grasses?

My answer is to try to break the diversity into smaller groups. You could try to learn the names of the species around you, by learning some of the more common or charismatic species, or the one’s that are most useful to us. Another approach is to learn the species that are found in specific regions (i.e. a region’s flora). Many floras still contain far more species than is tractable (usually far more the number of birds or mammals in a region). Then the solution is to become familiar with the most common plant families and try to learn a few species in each group. This is my approach to learning the trees of southern Africa.

Southern Africa is home to many trees: by some estimates there are over 2100 tree species native to the region. This number is more than double the number of bird species (~900 species) and more than five-fold the number of mammals (~400 species). With such a large number it is easy to become overwhelmed by the diversity; to see a sea of green rather than a forest of individual species. Fortunately, there is a surprisingly simple way to wrap your head around southern Africa’s trees. Approximately 1345 species of the region’s tree flora – roughly 65%…about two-thirds…or (ahem) most of the trees – are contained in just 20 plant families. If you learn these twenty families, you can just about call yourself a budding arborist.

The blogposts that I have written here will hopefully introduce you to some of southern Africa’s remarkable trees. I will try to describe the twenty largest tree families in an engaging way: by briefly introducing some of their identifying features, describing commonly occurring or familiar species and some of their uses, and bringing to life some of the unique aspects of their ecology or taxonomy.

Southern Africa’s “top ten” largest tree families:

  1. Rubiaceae
  2. Fabaceae (including the narrowly defined “families” Fabaceae, Mimosaceae and Caesalpiniaceae)
  3. Celastraceae
  4. Euphorbiaceae
  5. Anacardiaceae
  6. Proteaceae
  7. Combretaceae
  8. Ebenaceae
  9. Asteraceae
  10. Phyllanthaceae