Is Japanese Knotweed Dangerous?

IS JAPANESE KNOTWEED DANGEROUS?

You’ve probably heard by now some of the horror stories of Japanese knotweed, (Fallopia japonica).

Structural damage, decimated property values and mortgage providers refusing to lend. These are all possible consequences of an untreated knotweed infestation.

Maybe you’ve heard about how the ongoing invasion of Japanese knotweed damages biodiversity by supressing native species.

Perhaps you’ve read about people being injured by other invasive species like giant hogweed (Heracleum mantegazzianum).

Nobody wants to see knotweed on their property for a number of very good reasons, but is Japanese knotweed dangerous? Could contact with it harm people or pets?

Well, the good news is that Japanese knotweed is non-toxic and perfectly safe to handle. Despite its fearsome reputation, it is completely harmless to humans and animals.

In fact, Japanese knotweed is edible! The young shoots can be eaten raw or made into pies, crumbles, pickles and chutneys, or any recipe which calls for rhubarb. The older stems which are too tough to eat can be made into syrup for flavouring soft drinks or cocktails. Flower buds can be used for fermentation, to make wine and beer.

Japanese knotweed has been used for centuries in traditional medicine. Known in China as Hu Zhang, the dried root is used to treat many ailments including jaundice, coughs, congestion, inflammation and snake bites. It is also gaining popularity in the world of alternative therapy, as it contains an anti-oxidant called resveratrol.

While the claims of snake oil manufacturers should be treated with caution, resveratrol is also of interest to the scientific community as an anti-inflammatory, cardioprotective and anti-carcinogen. Clinical trials are yet to be completed, however.

You can visit the Japanese Knotweed Agency Gallery here and see what Japanese Knotweed looks like through the 4 seasons to help you easily identify the dreaded weed at the earliest opportunity. And there’s a whole load of real-life photos taken by the Agency Surveyors across the UK, to give you a feel of how rampant this weed is and how it can literally grow anywhere.

If you are unsure whether the suspect plant or weed is indeed Japanese Knotweed of a kind, you can submit a photograph to us here at the Japanese Knotweed Agency and one of our surveyors will assess and confirm whether it is or isn’t Knotweed, typically within just a few hours. Use our free identification service here.