Beauty
Appearances are deceiving; the most beautiful of things can be deadly.
The flower was called Nerium oleander, one of the most poisonous in the world, and Ironhide was seriously regretting the 'no harming humans' rule, because he wanted to kill the idiot who decided to use the flower as a centerpiece in the rec room.
Annabelle, who had recently learned that some flowers were edible, had mistaken the dangerous flora as something she could consume.
Ratchet had been able to concoct an antidote almost immediately, but Hide was still in a terribly foul mood, and probably would remain so until the medic released Anna from the sick-bay.
He wondered if Optimus would allow him to at least horribly terrify the moron whose fault it was, because he most certainly would find that out.