How to Identify and Eradicate Japanese Knotweed

Does Japanese Knotweed concern you? If it does, then I believe you are fully aware that you need to identify and eradicate Japanese Knotweed.



Japanese Knotweed is native to eastern Asia, Japan, China, and Korea. The large, herbaceous, perennial plant has hallow stems with raised nodes that are quite distinctive giving it the appearance of a bamboo. At first, red or purple shoots will appear and form rapidly growing canes. The canes will often have a purple speck.



Normally, the plants will be smaller but they may reach a height of three to four meters in growing seasons. Often, when the plants are smaller they should be cut down as they may sprout through the cracks in pavements. The leaves are broad oval and have a truncated base and are 7 to 14 centimeters long and 5 to 12 centimeters broad. The flowers are creamy white and can grow up to 6 to 15 centimeter long in late summer and in early autumn. The stems can be spiky, too.



One might want to eradicate the Japanese Knotweed after identifying it because it is considered invasive. It is often found on roadsides or waste places. However, the flowers from Japanese Knotweeds are often valued by some as a source of nectar for honeybees. They yield monofloral honey called bamboo honey in the United States.



Killing Japanese Knotweed requires time and it is not easy. First you will have to contain it. Start by using the biggest plastic or poly tarps that you can find to cover it. If you're going to use this tarp in the early spring then the growth of the weeds will be greatly hindered.



The Japanese Knotweed will cause problems even if it is covered, let alone if it is not. In Japan, it is known as "itadori" or strong plant. The new shoots will push your tarp up, if they are old shoots, but if you walk on them, you can trample them and hinder their growth. The tarps must cover everything completely and should not allow sunlight into the weeds. This way growth will be slowed even if it occurs. If you remove the old shoots, the new ones will not puncture your tarp, as the old ones can even go through concrete.



You won't get rid of your weeds by cutting them in the summer but you will hinder their growth. Remember that any remainders of the Japanese Knotweed can cause new weeds to grow so don't leave any. Bag all of the remainders. This entails a lot of hard work and it's probably not the best way to get rid of the weeds.



There are several methods of eradicating the Japanese Knotweed. One method is to remove the whole plant including roots and runners then dispose it in a dumpster. If you don't do this, it will crop up again from where you have tried to eradicate it.



Another way to eradicate the Japanese Knotweed is to cut the stem two inches above the ground level. Once this is done, apply a 25% solution of glyphosate or triclopyr and water to the cross-sectioned area.



One can also spray larger infestations with a 2% solution of glyphosate or triclopyr and water.



Some experts say, the fact that Japanese Knotweed can be dormant for a long time can make its eradication quite difficult. If one smothers it then it may quit growing temporarily. However, it will only be dormant and not dead. Some people say it may stay dormant for at least 20 years. This is why it needs to be dead before you remove any tarp you might have placed down or it may grow again.



Japanese Knotweed is a though weed and can be difficult to eradicate. However, with this knowledge at hand it can be possible.

Jo is an writer for Japanese Knotweed Solutions, (http://www.jksl.com), experts in Japanese Knotweed removal. If you are a devoted gardener, a home builder or a lover of nature, sooner or later you will stumble upon this pervasive nuisance. Japanese Knotweed is one of the most damaging weeds, causing colossal amounts of damage each year to domestic property, public building, and the environment.