Black sugar ants

Seeing these guys lately, they seem to be going to the buds to feed. Not scavenging dead bugs and no aphids that i can see. They just seem to wander around this plant in particular. Ferts were big bloom then tiger bloom. Some btk a couple weeks ago. Northeast locale, cool and overcast. No damage, anybody know what they are up to?
They are all over one of mine. Has all these brown sucker things on it too, idk if that had to do with it or not but they didn't really touch the other five out there.