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Invasive Species

While thousands of dollars are spent each year targeting weed species on Illinois’ highways, this plant continues its spread due to the lack of knowledge needed to reduce its spread and the means by which it is unknowingly spread. To learn more about the teasel growth cycle click here.

Teasel: Teasel is an aggressive monocarpic biennial invasive species known to create a monoculture which smothers out desirable native vegetation and roadside grasses. Teasel is not controlled by mowing. Mowing can actually cause this plant to live more than 2 years. Allowed to flower, each plant is capable of producing 6,000 seeds. Mowing the teasel after it has flowered can cause the seeds to be dispersed over a greater area.