Definition of knotweed
: any of several herbs (genus Polygonum) of the buckwheat family with leaves and bracts jointed and having a very short petiole; broadly : polygonum
Recent Examples of knotweed from the Web
Once the site of a 19th century shantytown populated by poor Irish immigrants, the hillside is blanketed today by Japanese knotweed and inhabited by an extensive homeless encampment along the river's edge.
Here the staff has rooted out nonnative honeysuckles and knotweeds throughout groves of maple, beech, hickory, sweet gum, oak, ash and tulip trees.
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'knotweed.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
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