Brown Scale. Bayer systemic, and spray with Neem oil solution. (If it was a nut bearing tree you wouldn't be able to eat the nuts after applying systemic insecticides).
An early stage of Scale insects includes wings if the plant they are hatched upon is overburdened with brethren. Your's is. They then fly to a new host. At that stage they are very tiny and just visible to the naked eye. Spraying is in order to suffocate those in-place and to get any loose critters. Systemic is to poison those feeding on the host, especially, those hidden from view and spraying. They are hermaphrodites: if one escapes death, he/she/it can re-arrange its sex and fertilizer herself. Hence, miss a single one and you have a new population.
Or, take it outside and set it on fire.