This name may not mean anything to you but you have certainly all seen one day when the other Japan’s knotweed. This plant, once imported from Japan colonizes many species today at a worrying speed and has become a nightmare despite the many grubbing campaigns! Click here for japanese knotweed control.
You do not have to be an expert in botany to know for sure a Japanese knotweed . It belongs to the family of polygonaceae just like all other species of the genus, however much less problematic. Visit this site for japanese knotweed control.
The Japanese knotweed is a perennial plant that we recognize the following criteria:
– Its shape is bushy and the density of stems present in m² is impressive. It often reaches a height of 3 m high for several tens of m² spreading as the tough strain spreads.
– Its summer bloom: from July to September in large erect and thin inflorescences, composed of a multitude of white flowers.
– Its tender leaves, both triangular and rounded at least fifteen centimeters in length,
– Its broad, round and hollow stems a little like bamboo. They are also full of water, brittle and flecked with small purple dots.
– Its roots and underground rhizomes very tough and invasive. As an indication, rhizomes of Japanese Knotweed can be up to 20 m long and thus form a new colony far removed from the original colony. In the same way, they will be able to bury themselves to 3 m of depth, from where the difficulty to eradicate completely this invincible perennial!
– Its extremely rapid growth: up to 2 m high in 2 weeks. Its rhizomes are spread in the soil up to 5 cm per day.
The cycle to remember
This plant has an annual vegetative cycle. That’s why the foliage disappears every year. The energy of the plant is then stored in the rhizomes that will give birth the next spring to more stems. Insensitive to frost, its rhizomes so deep will allow it to withstand temperatures well below -20 ° C.
As for its habitat, it mainly appreciates open and humid areas, which is why it is very easy to set up along watercourses. What is paradoxical is that it does not support root asphyxiation but it has, here again, an incredible trick: it sets its roots up to 1 m below the watercourse!