Japanese Knotweed (Polygonum) – Identification

Q: We have had this vine pop up all over the place on the side of our house. Any idea if it’s friend or foe?


Your plant is Japanese knotweed, Polygonum compactum, and it will quickly spread to unwanted parts of your landscape. If you get it while it’s just starting out you can control sprouts with glyphosate (click for sources).

Don’t delay….this plant is TROUBLE.

Oddly enough, in the past decade you may have seen ads for the health-giving properties of resveritrol, commonly found in grape skins. Resveritrol is sold as a memory enhancer and anti-oxidant. Though grapes contain a lot of the chemical, Polygonum roots have become the source of several resveritrol products.

Polygonum may have health benefits…..but let other people grow it.

Resveratrol improves learning

Medical Attributes of Polygonum cuspidatum

Resveratrol Isolated from Polygonum cuspidatum Root Prevents Tumor Growth

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