A quick guide to spotting Japanese knotweed rhizomes
Even when you know what you’re looking for knotweed rhizomes are not easy to find! The roots of the knotweed plant are buried deep in the ground and it takes close inspection to see the brown (often hairy) roots. But snap them open and you can easily see if it’s knotweed by the bright orange fibrous interior. This colouration is one of the main characteristics of knotweed, but it does take a highly trained eye to spot it!
what to look for:
- Rhizomes can grow up to 2 meters deep and 7 meters horizontally from the main plant.
- They have a dark brown exterior (made hard to spot when also embedded in dark brown mud) and a fibrous outer texture.
- The size and thickness of the rhizome depends on it’s age, also it’s location and whether it has been allowed to grow unimpeded.
- Sometimes when the rhizomes grow in restricted areas or underneath hard surfaces such as concrete they form thinner roots or look like spaghetti.
- When fresh, they are brittle and snap easily, similar to a carrot.
Pictures of knotweed rhizomes
Here are some lovely examples of knotweed rhizomes found on various contracts to help with knotweed identification.
Get trained to spot knotweed
Knotweed identification is best left to the experts, however we do offer training courses to assist with spotting knotweed rhizomes in the ground when onsite.
Our training has been developed in-house by experts plus we can create a bespoke training course to suit your needs.
Ideal for anyone working in the construction industry, property or land owners.