Interesting Facts About Japanese Knotweedchina waste

Japanese knotweed comes by many names; it is also known as Fallopia japonica, Polygonum cuspidatum and Reynoutria Japonicath. This is a large herbaceous plant that is found in Japan, Korea and China. Today, the Japanese knotweed can be found in Europe and North America. It has adapted itself in many countries to be classified as an invasive species.


The Japanese knotweed is part of the Polygonaceae family which sports hollow stems and distinct raised nodes like the bamboo although it has no relations with that species. This plant sports white stems that can grow up to 3 or 4 meters. This plant is versatile enough to sprout through cracks; hence, they are often cut down to prevent an overgrowth. Its broad oval leaves stem from a truncated base about 5cm to 12 cm broad and 7cm to 14cm long. Its small flowers are either creamy or white in color; they can sprout as long as 15cm long. The blooms come in the late summer or early autumn.


The Japanese knotweed is known to be closely related to the Russian vine and the infamous giant knotweed. It is also known as fleece flower, the Himalayan fleece vine, Huzhang which means tiger stick, the monkey weed or monkey fungus.

Some call the Japanese knotweed as Hancock’s curse, pea shooters or elephant ears. Although it is not a rhubarb plant, it has been called the donkey rhubarb or sally rhubarb. It is not part of the bamboo species but it has been called Japanese bamboo, Mexican bamboo or American bamboo. It comes by a plethora of regional names with some confusion as sorrel.

Its Japanese name is itadori.


The Japanese knotweed is best known as an invasive weed in Europe and the U.S.; hence, it is noted as such by the World Conservation Union.

This weed has an invasive root system that grows so strong that it can easily damage concrete surfaces; be it foundations, roads, buildings, pavements, flood defenses, architectural sites and retaining walls. It is widely present in temperate ecosystems, waste sites and roadsides.

Growth pattern

The Japanese knotweed grows in dense colonies which easily crowd out other herbaceous plants. Its tolerance to a wide range of temperate, pH and soil types encourage its growth. It can withstand climate of −35 °C with a spread of 7 meters and a depth of 3 meters; hence, to remove it by excavation is extremely hard and tedious.

This weed is resilient to cutting with a vigorous re-sprouting from its deeply entrenched roots.

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