Japanese Knotweed


Posted by admin | Posted in Japanese Knotweed | Posted on 23-09-2010

Tags: ,

I was always told that when plants are weedy in an area, it’s because there is a need for them. Maybe we don’t see it, it’s hard to appreciate kudzu in the South, but there’s a need. Japanese knotweed is one such plant.

Otherwise known as Polygonum cuspidatum this plant in the Polygonaceae family has been called Mexican bamboo, Japanese fleeceflower, giant knotweed, and Huzhang

Description: Japanese knotweed is a large, robust perennial that spreads by long creeping rhizomes to form dense thickets. The stems are stout, cane-like, reddish-brown, 4 to 9 feet tall. The plants die back at the end of the growing season. The stem nodes are swollen and surrounded by thin papery sheaths. The leaves are short-petioled, 2 to 6 inches long and about two-thirds as wide, egg-shaped and narrowed to a point at the tip. The flowers are small, creamy white to greenish white, and grow in showy plume-like, branched clusters from leaf axils near the ends of the stems. The fruit is 3-sided, black and shiny.

Cultivation: Japanese knotweed grows quickly and aggressively. Large dense thickets form rapidly and shade out other plants. It can tolerate partial shade and is most competitive in moist, rich soil. Japanese knotweed is commonly found along roadsides and on stream banks. The thickets can completely clog small waterways and displace all other streamside vegetation. Knotweed can increase bank erosion and lower the quality of riparian habitat for fish and wildlife.

Properties: antiarthritic, antirheumatic, analgesic, detoxicant, antitussive, expectorant, antibacterial, antiviral, antioxidant

Medicinal Uses: In China, the root was used medicinally to treat menstrual and postpartum difficulties. In recent years, the Chinese have been using huzhang in the treatment of burns and acute viral hepatitis with considerable success. Researchers have found that some of its chemical components have antibacterial, antiviral, liver protectant and antioxidant effects. The unique broad, traditional and modern properties which include detoxicant, antiburn, wound healing, astringent, antimicrobial and antioxidant, have been utilized in skin care cosmetics and environmental products. Its extracts are used in skin lotions, antifatigue, massage and cleansing creams as well as in an herbal disinfectant approved by the US EPA.

: painful joints, jaundice, menstrual difficulties, cough with excessive phlegm, skin sores and boils, traumatic injuries

Culinary Uses: It is an extremely valuable and versatile food resource. The young shoots (up to 1′) canbe served like asparagus but with a flavor all their own. Gather in the early spring, selecting shoots with the thickest stems. Wash well and remove any leaves on the stalks. Place in a pan with about 1 inch of water or cook in a vegetable steamer. The stems cook quickly; in about 5 minutes they will turn a creamy olive green. They will be soft when pricked with a fork when done. Do not overcook. Drain and serve hot with melted butter or hollandaise sauce. The tender shoots can also be pureed with milk, salt and pepper to make a soup. Slightly older stems can be peeled and the sour rind boiled with sugar and pectin to make a rhubarb-like jam, sauces and pies.

Japanese Knotweed Purée

Gather stalks, choosing those with thick stems. Wash well and remove all leaves and tips. Slice stems into 1-inch pieces, put into a pot and add ¾ cup sugar for every 5 cups of stems. Let stand 20 minutes to extract juices. Add only enough water to keep from scorching, about half a cup. Cook until pieces are soft, adding more water if necessary. They will cook quickly. When done, the Japanese Knotweed needs only to be mixed with a spoon. Add lemon juice to taste and more sugar if desired. Serve chilled for dessert just as it is, or pass a bowl of whipped cream. This purée is excellent spooned over vanilla ice cream or baked in a pie shell. Keeps well in the refrigerator and may be frozen for later use. (City Herbal)

Japanese Knotweed Bread
2 cups unbleached flour
½ cup sugar
1 ½ tsp baking powder
1 tsp salt
1 egg
2 Tbsp salad oil
¾ cup orange juice
¾ cup chopped hazelnuts
1 cup sweetened Japanese Knotweed Purée
Preheat oven to 350F. Sift dry ingredients together into a large bowl. Beat the egg white with the oil and orange juice. Add along with hazelnuts and purée to dry ingredients. Do not mix until all ingredients are added, and blend only enough to moisten. Do not overmix. Spoon gently into buttered 91/2-by-5-by-3-inch loaf pan. Bake about 1 hour or until a straw or cake tester inserted in the center comes out dry. Cool by removing from pan and placing it on a rack. For muffins, spoon into buttered muffin tins and bake about 25 minutes. (A City Herbal)

A City Herbal, Maida Silverman, Alfred A Knopf, 1977; ISBN: 0-394-49852-6
Better Health with (Mostly) Chinese Herbs and Foods, Albert Y Leung, AYSL Corp, 1995; ISBN: 0-9634979-1-X
Exploring Nature’s Uncultivated Garden, Deborah Lee, Havelin Communications, 1988; ISBN: 0-925909-00-9
Wild Food, Roger Philips, Little Brown, 1986; ISNB: 0-316-70611-6

HERBALPEDIA™ is brought to you by The Herb Growing & Marketing Network, PO Box 245, Silver Spring, PA 17575-0245; 717-393-3295; FAX: 717-393-9261; email: herbworld@aol.com URL: http://www.herbalpedia.com Editor: Maureen Rogers. Copyright 2006. All rights reserved. Material herein is derived from journals, textbooks, etc. THGMN cannot be held responsible for the validity of the information contained in any reference noted herein, for the misuse of information or any adverse effects by use of any stated material presented

Share this:
Share this page via Email Share this page via Stumble Upon Share this page via Digg this Share this page via Facebook Share this page via Twitter