Knotweed

Or, Japanese Knotweed, as it's called - to reinforce the idea that some doggone foreigners are responsible for this sneaky, invasive unwanted plant of the wetlands and beyond. Hmmm, it's also known as Mexican Bamboo - huh? 

But, you (we Americans) can fight back by eating their (click) young as they emerge, innocently from the soil in early Spring. You can also join the Japanese Knotweed Alliance

...and learn to fight back in other ways, as well. Canalphotos, in typical oppositional thought, loves the plant.