We've discussed many different methods of manual invasive treatments for knotweed, but a relatively new and unexplored method of control lies in the depths of the Calkins Trail at the Intervale. Once you know where to look, a short walk through some malicious stinging nettle leads you to a tree surrounded by knotweed. The knotweed at this site is growing through a sheet of wire mesh on the ground. At first glance, one wouldn't understand the purpose of the mesh. All of the plants seem to be doing just fine. Once you take a closer look, however, you can see a big clump of neon pink hairs at the base of the larger stalks. Does this method suppress knotweed or does it simply give the plant a fashionable tutu?
Mesh girdling, or MeshTech, is a method in which one removes all of the surface growth of knotweed and then covers the area with wire-fence mesh. The knotweed then grows through the mesh openings. As the stalks become fatter, the mesh constricts the plant like a corset that's too tight.
Ideally, the knotweed then suffocates to death. But if we've learned anything from evolution, nature can often find a way. Heck, a snapping turtle has learnt to breathe out of its butt. Knotweed is no exception to the resilience of nature in the face of adversity. It seems that when the stalk becomes thick and realizes that it's getting strangled, its base laterally spreads by shooting out hundreds of tiny pink rhizomes. Japanese knotweed is a plant that spreads through vegetative regeneration, so it's no surprise that its stem quickly figured out a way to overcome the wrath of the mesh. But is all hope lost? Maybe not. After all, the mesh has only been at this site for about a year. According to Alexander Dayes, the managing director at Japanese Knotweed Solutions Ltd, it will take 3-5 years to see any success. After a few years of fighting the girdle and using up its carbohydrate storage, the knotweed will hopefully lay down its sword.