Papaver dubium or a species of poppy or “Nagami hinageshi” shows its cute orange flowers at the early summer.
The flower of the top of a long delicate cane produces a fruit looks like a man with an umbrella hat. Surprisingly, these pods contain 1000 to 2000 small seeds inside and spread them EVERYWHERE! Well, count how many pods you can find in this picture, then multiply that number by, say, 1500, and guess what will happen following years!