Contact information
For information on Lakes in Wisconsin, contact:
Wisconsin DNR Lakes
Division of Water
Bureau of Water Quality
Aquatic Invasive Species Contacts

Japanese knotweed (Fallopia japonica) - Mill Creek

Status
Verified
Date First Found
10/6/2021
Location First Found
Near the northwest corner of the intersection of Silver Spring Lane and Kettleview Road. These coordinates represent a small area of Knotweed on State land along the roadway and along Mill Creek. There is an additional, much larger area of Knotweed directly across the road to the south, located on private land. It appears as though the Knotweed may have spread across the road. Coordinates of the large area across the road are 43.708973 / -88.040766. Estimated square meters includes both areas.
Latitude and Longitude
-88.040789, 43.709002


Japanese knotweed (Fallopia japonica)

About Japanese Knotweed

Japanese knotweed, in the buckwheat family, is a perennial that grows to heights of 5-10 feet in large clones up to several acres in size. The arching stems are hollow and bamboo-like, a reddish-brown to tan color;; they die, but remain upright through the winter. Mature leaves are 3-5 inches wide and 4-9 inches long, lighter on the lower surface, and egg to spade shaped;; young leaves are heart-shaped. Lacy 2 inch long clusters of tiny greenish-white flowers are produced in late summer and held upright at the leaf base. Japanese knotweed reproduces occasionally by seed, but spreads primarily by extensive networks of underground rhizomes, which can reach 6 feet deep, 60 feet long, and become strong enough to damage pavement and penetrate building foundations.