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Removing knotweed

Knotweed and how to remove it.

Knotweed, also known as Japanese Knotweed, is a highly invasive plant species that can grow up to 10 feet tall and spread rapidly, making it a significant threat to the environment and property. It has bamboo-like stems, broad leaves, and small white or greenish flowers.

Knotweed is one of the hardest weeds to remove from a garden. Introduced into the U.K. by a Victorian gardener the plant quickly became highly rated for use on large estates lakes and to provide shooting cover of game birds. When used on lakes it was ideal because of the ability to grow quickly and to stop erosion. However the plant natural extended it range and soon spread in an uncontrolled manor throughout the U.K. Today it is a registered weed and it is a civil offence to aid in its spread.

To remove knotweed, the best approach depends on the severity of the infestation. Here are a few methods:

  1. Chemical Treatment: This is the most effective method for removing knotweed. It involves applying a systemic herbicide containing glyphosate or triclopyr to the plant’s leaves. The herbicide will travel through the plant and kill the entire root system. This method may require multiple treatments over several years to fully eradicate the knotweed.
  2. Digging: This method involves digging out the entire root system of the plant, including all the rhizomes. Rhizomes are the underground stems of knotweed that can regenerate the plant. Make sure to dispose of the plant material carefully, as it can regrow from even small fragments.
  3. Covering: Covering the knotweed with a thick, non-permeable material such as black plastic can prevent sunlight from reaching the plant and eventually kill it. However, this method may take several years to be effective.
  4. Professional Removal: If the knotweed infestation is severe, it’s best to seek the help of a professional removal service. These experts will have the equipment and knowledge to safely remove the plant and prevent it from spreading.

No matter which method you choose, it’s important to monitor the area regularly to ensure that the knotweed does not return.