Can anyone give me an ID of this plant? It is growing wild in a potential restoration site. It looks somewhat Petasites but I can't seem to pin it down. It is about 4 feet tall, with very large leaves (foot and a half). Also - I assume it is a non-native to Washington State and wondering if anyone has seen it become a problem (spreading, weedy, etc).
Yes, Petasites japonicus var. giganteus (and here, too). On a restoration site, I'd do my best to get rid of it. It can be very aggressive along watercourses.
Thanks - That is what I thought it was. My problem is that the japonicus seems to have a different shaped leaf. This one the stem is attached to the center of the leaf (see another photo I've attached), whereas japonicus seems to be attached on the side with a kind of heart-shaped lobe around it (for example where the guy's hand is being 'eaten'). What do you think? Perhaps it was just some individual variety that I was looking at.
Hmmm... right you are. I missed that detail when first looking at it. How far is this site from some sort of disturbance (e.g., residential neighbourhood, power-line right-of-way)? I've had a look at the native Petasites species, and those can be ruled out. That inflorescence growing beneath the leaves sure reminds me of Petasites, but I've never seen one with a peltate leaf before.
It is in an area of past disturbance. The property has recently switched hands and the current landowner doesn't know the plant. It is actually growing on the edge of a small bamboo plantation where the prior landowner was harvesting bamboo. It is in a wetter area near a small ephemeral stream. The bamboo and this plant definitly give the area a tropical asian feel. I am assuming (perhaps wrongly) that this plant was planted as an ornamental. Maybe I'll try to track down the prior landowner. I agree that it definitely looks Petasites and the size is japonicus. Hmmm. No matter what it is - being a restoration site and non-native - I will try to control it.
I'd considered Astilboides tabularis, but the inflorescence seems to be off (if that's indeed the inflorescence of this plant in the second photograph). Would it be possible to get a scan / better photo of the inflorescence?
I just had a look at both plants outside my office - the petioles aren't smooth on either of the two, though rougher on the Astilboides. Seems to me that the Astilboides petioles would capture the light in a photo in a way that's been shown here. And, on third glance, I'm not certain that the inflorescence in image 2 belongs to this plant. So, I'm now leaning toward what saltcedar and levilya suggested.
Those ideas look good to me. I'll take a closer look at the inflourescence next time I'm in the area. Thanks for all the help.
