What are Some Natural Herbicides?
There are a number of natural pesticides available to gardeners for insect control, but relatively few natural herbicides for the eradication of weeds or other invasive plants. What natural herbicides do exist can do more harm than good if applied under the wrong conditions. However, there are plants that act as natural herbicides, such as black walnut, sunflowers, sagebrush and spotted knapweed. These plants excrete chemicals that can kill off another plant species growing nearby. The process of certain plants acting as natural herbicides is called allelopathy. Researchers are very interested in the allelopathic qualities of plants, since the chemicals responsible for natural herbicides can often be isolated and refined for commercial use. For example, scientists were able to extract an herbicidal chemical called catechin from the roots of spotted knapweed, an invasive weed found in the western United States. This chemical can be synthesized on a larger scale and applied to a number o
