Japanese knotweed invasion in the United States leads to falling house prices, but in China it becomes a delicious ingredient.

Huzhang, a decorative plant originating from Japan, was introduced to the United States in the late 19th century and became popular due to its vigorous growth. However, its invasive root system quickly spread, penetrating the ground and building foundations, becoming a challenging invasive species to eradicate. In 42 U.S. states, huzhang disrupts ecosystems, leading to a decline in property values, such as a 10% drop in home prices in certain communities in New York State.

In the UK, huzhang poses similarly severe problems, causing annual property value losses of up to £2 billion and removal costs of approximately £166 million. Its roots penetrate several meters underground and spread laterally up to 7 meters, and even if the plant is cut down, the roots can regenerate.

In East Asia, particularly in China, huzhang does not cause similar destruction. The local ecosystem coexists with huzhang, and herbivores and microorganisms control its spread. In China, huzhang is even regarded as a medicinal plant and a delicious food ingredient. Its tender stems are rich in fiber and vitamin C and can be served cold, pickled, or stir-fried.