据报载,美国南达科他州共有4种耐草甘膦的杂草,由于玉米与大豆轮作是该州主要的作物栽种模式,普通水萱麻成为受影响面积最大的杂草品种。30年前,水萱麻只有在该州东南部最远的地区有所发现,而之后直至现在已经成为一种难以根除的杂草。在上世纪八九十年代,玉米和豆类的轮作在南达科塔州的北部以及西部地区快速普及,水萱麻很快蔓延至北部以及西部。10年内水萱麻就成为南达科他州最主要的阔叶杂草。 It has been reported that four species of weed tolerant to glyphosate are present in South Dakota, United States. Because maize and soybean rotations are the dominant mode of crop planting in the state, common water marijuana is the most affected weed species. Thirty years ago, water hyssop found only in the furthest south-east of the state, and has since become an elusive weed. In the 1980s and 1990s, the rotation of maize and beans spread rapidly in the northern and western parts of South Dakota, and the water quickly spread to the north and west. Water marijuana became South South Dakota’s dominant broadleaf weed within 10 years.