It's an Arisaema of some sort.....like a jack-in-the-pulpit.

Pinellia ternatea, aka Crowdipper. An aroid, like jack in the pulpit. From Japan. Turns up in New Jersey from time to time. Does not seem to be terribly invasive. Interesting little species.

Interesting. This plant is a major invasive around Philadelphia, but in New Jersey it's not mentioned on any of several lengthy NJ invasive plant lists. I've only seen it once. I'll have to tell the locals to watch out for it.

I can't even begin to describe my hatred for Pinellia ternata!!! It's a nightmare! I'm at the point where I have started just pulling the tops to prevent reseeding. After years of digging, it is the only thing that is reducing the population. So glad I purchased "green dragons" on Ebay years ago. LOL

I hate it too, ademink! Terrible weed here in philadelphia. Dont let it drop those seeds, and dig up the bulblets as bes tyou can. Dispose of carefully. It WILL take over. It is terribly hard to get rid of and grows rampant here.