We see a spike of this once in a while out here. They're a European import from who knows when. They like damp partially shaded places and you don't even realize they're around until September when the seed ripen into spikes of brilliant orange-red.
So pretty!
And so poisonous!
The leaf shows up in the winter or early spring - a big arrow shaped thing that will disappear in the heat. Then in the summer, an inconspicuous flower spike will pop up that we don't even notice until it turns red, red, red.