Invasive plants (1mb PDF)  are non-native plants that, once introduced, have a negative impact on our environment, economy, and/or human health. At Pierce Cedar Creek Institute, invasive plants have been identified as a serious threat to our natural ecosystems. Once established, they out-compete native species, reducing biodiversity and altering ecosystem structure and composition. We make significant efforts each year to remove non-native plant species that pose a threat to our natural areas. While early detection and rapid responses are crucial for keeping newly established invasive plant populations in check, it is important to use appropriate control strategies and timing (26kb) when controlling the more established invasive plants. At the Institute, the land steward and stewardship volunteers regularly work to control autumn olive, garlic mustard, spotted knapweed, phragmites, purple loosestrife, and multiflora rose.