2. Invasive Species
Japanese Knotweed
Buckwheat family
(Lythraceae)
Scientific Name: Fallopia
japonica
Previously: Polygonum
cuspidatum
Common Names: Japanese
knotweed, fleece flower,
Mexican bamboo, huzhang
3. Distribution
Native to Asia
Colonized the United States in Late 1800’s
Introduced as an ornamental and for erosion control
Presently found in a significant portion of North America
5. Flowers
Flowers May to September
Flowers terminal and auxiliary
Branched sprays (racemes) 3-6 inches long
Covered with tiny 5-petaled (sepaled) white to greenish
flowers
3 styles and 8-10 stamens
6. Fruit
August – November
Dangling
Winged
1 triangular shiny nutlet
7. Life Cycle
Stems and leaves survive one season
Rhizomes survive many years
Grows fast in spring from rhizomes and seeds
Crowds/shades other species
Prefers open areas such as riparian corridors, roadways,
etc.
Does well in wetlands
11. Chemical Control Options
Renovate 3 as 2% solution
Glyphosate
Foliar application with 2% solution
Cut-stem application (label details)
Combination of Glyphosate (2%) and Renovate (1%)
Habitat as 1% solution
Early treatments prevent seed production
Late season treatments are more effective on rhizomes
12. Japanese Knotweed Sherbet
This sour rhubarb relative lends its lemony flavor and thickening
qualities to this sweet-tasting sherbet.3 cups Japanese knotweed stalks,
peeled if desired, coarsely sliced
1-1/3 cups orange juice (freshly squeezed is best)
1-1/2 cups apple juice or other fruit juice
1/2 cup lemon juice
1/4 cup canola oil
1/4 cup vegetable glycerin, honey, barley malt, or rice syrup
1 tbs. freshly grated (or 1 tsp. dried) orange rind
2 tsp. vanilla extract
1 tsp. lemon extract
1 tsp. liquid stevia (optional)
1/4 tsp. salt1.
1. Simmer the Japanese knotweed shoots in the orange juice, apple juice,
and lemon juice 10 minutes or until soft.
2. Puree in a blender with the remaining ingredients.
3. Chill.
4. Pour into an ice cream machine and run it until done.