How is gum arabic harvested from acacia trees?

Gum arabic is harvested from mature Acacia senegal and A. seyal trees, typically between 5 and 25 years old, at the end of the rainy season in sub-Saharan Africa.1

The harvesting process involves the following steps:

• Incisions: Workers make incisions in the stems and branches of the trees and strip away the surrounding bark.12
• Exudation: Over several weeks, the tree produces a gum exudate—a process known as gummosis—which seeps into the incisions as a protective mechanism.12
• Collection: As the substance dries upon exposure to air, it forms a nodule. These nodules are collected every two to four weeks.1
• Drying and Sorting: The collected nodules are dried completely in the sun, then visually inspected and sorted by size before being sold as crude or processed gum.1

While the trees produce this adhesive naturally, the intentional wounding of the bark is the standard method used to stimulate and manage the yield for commercial collection.12