Jeez, the meanings are not that different and they both describe the shape. Plume refers to a feathering shape, and bloom refers to a plant like shape. Picky as snot, if you want to start rifling through agates telling me one is more featherlike than treelike. Plume, bloom, dadgum English majors, ha ha. Don't you guys have some tables to bus or something?
Honestly, I don't care what we call it. It's like my wife when I refer to the Fermosa trees (the Southern trash tree that has the pretty pink Dr. Seuss looking blooms/plumes), she always tries to correct me that they are mimosa trees. I Googled it on one of our walks, and showed her where both words referred to the same damn tree. Sure, sure, the scientists call them Mimosas, but I'm an artist. I don't walk to the beat of the same fascist drummer. I'll call them flamingo trees if I feel like it. :
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