I might not know the technical term for a plant with multiple generations in a year. But I now know achaeophyte! That's an organism, like sheperd's-purse, that was pre-historically introduced to an area by humans. This was an Old World food plant back into pre-historical time. Or how about protoparasitic? The seeds of shepher'd-purse produce mucilage. There is a hypothesis that this traps bugs in the seeds, which then provide nutrients when they germinate. It might help explain why shepherd's-purse is so successful in environments like the one shown here. And at times like that. These mature plants were in Grand Rapids, Ohio, on April 20.