Common reed, Phragmites australis, grows throughout Minnesota in wet areas. Larger forms, left in photo are likely non-native. The native form is shorter, has smaller flowers that are light brown to beige in color, and the plants are often light green to yellow green. The larger form shown here has much wider leaves, bigger darker flowers, and the plants were an additional 3 feet in height ( I could not reach the base of the plant to cut it lower.)
Flowers from the native common reed, left; and exotic right in photo.