What are these brown blobs on my olive plant?

Dear Max Vernimmen, Possibly these creatures are alive and they suck plant sap, as a result leaves start to first yellowing or chlorotic. Subsequently, the entire canopy may turn to withering appearance. Finally, the plant may die or collapse if the insect fecundity is too high in favourable climate and suitable environment. So, you need to control simply by spraying with dish wash powder dissolved in water to dislodge quickly the creatures. We call these creatures to be definitely Brown Soft Scale. When they start to crawling out and dislodge, you can remove them by a hand brush or in case there's multiple trees pls spray any highly contact poisons like Chloropyrifos or Cypermethrin or Dimethoate. To know about the insect fecundity and control measures, pls ck in plantix library by clicking on green hyperlink and review 😂 Hope that it may be something like make it a better sense to figure out now😁!