Canada thistle

canada-thistle的词性：
n.（名词）

1. A perennial herb (Cirsium arvense) in the composite family, native to Europe and naturalized as a noxious weed in North America, having spiny-margined leaves and rose-purple or sometimes white flower heads.
田蓟：一种多年生菊科草本植物（丝路蓟 蓟属） ，原产于欧洲，在北美洲被划归为有害杂草， 长有带刺边的叶子和玫瑰紫或有时是白色的花苞