Animal damage to Quivertree

Observation - Animal damage to Quivertree - Southern Africa. Description: Past damage, but by what? Donkeys often chew them for water - presumably so would Zebra, but I dont think any are present. Possibly porcupines??
Past damage, but by what? Donkeys often chew them for water - presumably so would Zebra, but I dont think any are present.
Possibly porcupines??