Some websites say they are poisonous and some not. Jack had his leash wrapped around some of these (or cosmos) when I got home (he has to be tied up or he takes off). I wondered if he inhaled the dust from the plant and it made him sick. Its possible so I better get rid of all of them. I never pull them out so they drop the seeds. I found nothing that said cosmos were poison.
I have some Lily of the Valley but he wasn't by those