Japanese Knotweed By Linda Tucker

Polygonum cupsidatum Also called Fallopia joponica Also called Fallopia joponica Buckwheat family (Polygonaceae) Buckwheat family (Polygonaceae) Common names: Common names: Japanese Knotweed Japanese Knotweed Mexican Bamboo Mexican Bamboo Chinese Chokeweed Chinese Chokeweed Native to eastern Asia Native to eastern Asia

How Did it Get Here? First introduced from Japan into the United Kingdom in 1825 First introduced from Japan into the United Kingdom in 1825 Was introduced to the United States from the U.K. in the late 1800s Was introduced to the United States from the U.K. in the late 1800s Introduced as an ornamental plant Introduced as an ornamental plant In recent history, heavily planted at mine reclamation sites in PA In recent history, heavily planted at mine reclamation sites in PA

About the Plant Perennial Perennial Grows between 3 and 10 feet high Grows between 3 and 10 feet high Stems are reddish green, jointed, and hollow Stems are reddish green, jointed, and hollow Broad, alternate leaves Broad, alternate leaves Flowers: small and greenish white and grow in spikes Flowers: small and greenish white and grow in spikes

What Does It Look Like?

Where is it Found? Moist environments, such as stream banks, islands, and wetlands Moist environments, such as stream banks, islands, and wetlands Also found along roadsides and railroads Also found along roadsides and railroads Can live in open sun or partial shade Can live in open sun or partial shade Can tolerate harsh conditions such as high temperatures, high salinity, droughts, and floods Can tolerate harsh conditions such as high temperatures, high salinity, droughts, and floods

Distribution

How Does it Spread? Reproduces through two methods: Reproduces through two methods: Seeds Seeds Fragmentation of the rhizome Fragmentation of the rhizome Rhizome can be 40 to 60 feet in length Rhizome can be 40 to 60 feet in length

Ecological Impacts Japanese knotweed grows quickly and densely Japanese knotweed grows quickly and densely Crowds out native plants and limits biodiversity Crowds out native plants and limits biodiversity Causes stream banks to be less stable and susceptible to erosion during floods Causes stream banks to be less stable and susceptible to erosion during floods

Urban Impacts

How to Get Rid of It Eradication is very difficult Eradication is very difficult If it is cut, it will grow back due to the rhizome If it is cut, it will grow back due to the rhizome It can be dug up, but any remaining rhizome can grow back and you can actually spread the rhizome this way It can be dug up, but any remaining rhizome can grow back and you can actually spread the rhizome this way Herbicides such as Glyphosate and Triclopyr can be used effectively in combination with cutting Herbicides such as Glyphosate and Triclopyr can be used effectively in combination with cutting

How to Prevent Spreading Dont plant Japanese Knotweed Dont plant Japanese Knotweed Wash your shoes before entering and after leaving natural areas to remove seeds Wash your shoes before entering and after leaving natural areas to remove seeds Do not dig up the rhizome, as you may accidentally spread rhizome fragments Do not dig up the rhizome, as you may accidentally spread rhizome fragments

Some Positive Qualities Excellent source of vitamins A and C Excellent source of vitamins A and C Good source of resveratrol, which can lower bad cholesterol and reduce the risk of heart attack Good source of resveratrol, which can lower bad cholesterol and reduce the risk of heart attack Tastes similar to rhubarb and can be used in baked goods, soups, marmalades, or just steamed and eaten Tastes similar to rhubarb and can be used in baked goods, soups, marmalades, or just steamed and eaten

References d.pdf d.pdf d.pdf d.pdf anese_knotweed_control.pdf anese_knotweed_control.pdf anese_knotweed_control.pdf anese_knotweed_control.pdf /Knotweed.html /Knotweed.html /Knotweed.html /Knotweed.html orial/japanese_knotweed.htm orial/japanese_knotweed.htm orial/japanese_knotweed.htm orial/japanese_knotweed.htm

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