The Fever Thorn Tree is a very common tree in the African bush. According to WILDwatch.com the trees are often found in poorly drained clay soil next to lakes and rivers and has a fairly shallow root system that reduces the possibility of water-logging.
The thorns on these trees are long and extremely sharp - I've been stabbed several times. The amazing thing though is that elephants pull the leaves off the tree to feed to their young, and themselves eat the pods and branches (reference). Wow! Imagine eating one of these branches - especially without thumbs! :D