Native American ethnobotany
This is a list of plants used by the indigenous people of North America. For lists pertaining specifically to the Cherokee, Iroquois, Navajo, and Zuni, see Cherokee ethnobotany, Iroquois ethnobotany, Navajo ethnobotany, and Zuni ethnobotany. E. The entire echinacea plant is used medicinally, both dried and fresh. Common preparations include making a decoction or infusion of the roots and leaves, making a poultice of parts of the plant, juicing the root or simply using the leaves as they were. Echinacea contains essential oils and polysaccharides that boost the immune system, leading to a faster recovery from various  illnesses. Due to this property, echinacea has been commercialized and has had clinical trials support that it reduces the duration of a cold by 1–4 days and reduces the chance of developing a cold by 58%. Witch hazel works as an astringent, a substance that causes the constriction of body tissues. The tannins and flavonoids found in witch hazel have astringent and antioxidant properties, respectively, which are thought to contract and protect blood vessels, thereby reducing inflammation. However, modern witch hazel extracts are often distilled and do not contain tannins due to health concerns. W. Willow bark contains salicin, a  compound similar to aspirin that has anti-inflammatory, antipyretic, and analgesic properties. The following table examines why various tribes use willow. One reason for the vast differences in the use of the willow is that there are many ways to prepare it and these different preparations allow for it to be utilized in different ways. For example, the Thompson people would make a concoction of wood, willow, soapberry branches and "anything weeds" to treat broken bones. If they wanted to treat a cold, however, the Thompson people would make a decoction of red willow branches and wild rose roots. Native