Attempts to improve conditions tend to reduce yield. Gum from wild trees is variable and somewhat darker colored than that from cultivated plants. Collected gum is carefully freed of extraneous matter, sorted and sometimes ripened in sun before export. Gum arabic is oderless with a bland taste, yellowish and some tears are vermiform in shape. Ripened or bleached gum occurs in rounded or ovoid tears over 2.5 cm in diameter, and in broken fragments.
Tears are nearly white or pale yellow and break readily with a glassy fracture.
Gum arabic is important export product for some areas in tropical Africa and Mauritania. From Africa some genuine gum is shipped to India then to Europe and America. Biotic Factors Fungi reported on this crop are Cladosporium herbarum, Fusarum sp., Ravenelia acaciae-senegalae and R. acaciocola . Many insect visitors mimic the plant, the buffalo treehopper, Stictocephala bisonia , being a good example. References Cheema, M.S.Z.A. and Qadir, S.A. 1973.