My plant focus was the switch cane or Arundinaria tecta. Although the one in the picture could also be river cane. They are sometimes hybridized. But Switch Cane much like other grasses is a monocot! They can form large patches called cane breaks that are actually an endangered ecosystem. These are the one of only 4 species of bamboo native to the US. They were often used for building material and tool making. I saw quite a bit of it walking up and down the flood planes!