Wild Olive Pests

[Namibian Bosman]

I have a wild olive in my garden in Windhoek - Namibia.
It has some strange pests on about 5% of the leaves.

Does anyone know what it is and how to treat it?

 

[Chuck]

I have a wild olive in my garden in Windhoek - Namibia.
It has some strange pests on about 5% of the leaves.

Does anyone know what it is and how to treat it?


View attachment 67714

Will they rub off of the leaf fairly easy?